Search results for: quasi-elastic release
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 1221

Search results for: quasi-elastic release

1131 Polymeric Microspheres for Bone Tissue Engineering

Authors: Yamina Boukari, Nashiru Billa, Andrew Morris, Stephen Doughty, Kevin Shakesheff

Abstract:

Poly (lactic-co-glycolic) acid (PLGA) is a synthetic polymer that can be used in bone tissue engineering with the aim of creating a scaffold in order to support the growth of cells. The formation of microspheres from this polymer is an attractive strategy that would allow for the development of an injectable system, hence avoiding invasive surgical procedures. The aim of this study was to develop a microsphere delivery system for use as an injectable scaffold in bone tissue engineering and evaluate various formulation parameters on its properties. Porous and lysozyme-containing PLGA microspheres were prepared using the double emulsion solvent evaporation method from various molecular weights (MW). Scaffolds were formed by sintering to contain 1 -3mg of lysozyme per gram of scaffold. The mechanical and physical properties of the scaffolds were assessed along with the release of lysozyme, which was used as a model protein. The MW of PLGA was found to have an influence on microsphere size during fabrication, with increased MW leading to an increased microsphere diameter. An inversely proportional relationship was displayed between PLGA MW and mechanical strength of formed scaffolds across loadings for low, intermediate and high MW respectively. Lysozyme release from both microspheres and formed scaffolds showed an initial burst release phase, with both microspheres and scaffolds fabricated using high MW PLGA showing the lowest protein release. Following the initial burst phase, the profiles for each MW followed a similar slow release over 30 days. Overall, the results of this study demonstrate that lysozyme can be successfully incorporated into porous PLGA scaffolds and released over 30 days in vitro, and that varying the MW of the PLGA can be used as a method of altering the physical properties of the resulting scaffolds.

Keywords: bone, microspheres, PLGA, tissue engineering

Procedia PDF Downloads 407
1130 Formulation and In vivo Evaluation of Venlafaxine Hydrochloride Long Acting Tablet

Authors: Abdulwahhab Khedr, Tamer Shehata, Hanaa El-Ghamry

Abstract:

Venlafaxine HCl is a novel antidepressant drug used in the treatment of major depressive disorder, generalized anxiety disorder, social anxiety disorder and panic disorder. Conventional therapeutic regimens with venlafaxine HCl immediate-release dosage forms require frequent dosing due to short elimination half-life of the drug and reduced bioavailability. Hence, this study was carried out to develop sustained-release dosage forms of venlafaxine HCl to reduce its dosing frequency, to improve patient compliance and to reduce side effects of the drug. The polymers used were hydroxypropylmethyl cellulose, xanthan gum, sodium alginate, sodium carboxymethyl cellulose, Carbopol 940 and ethyl cellulose. The physical properties of the prepared tablets including tablet thickness, diameter, weight uniformity, content uniformity, hardness and friability were evaluated. Also, the in-vitro release of venlafaxine HCl from different matrix tablets was studied. Based on physical characters and in-vitro release profiles, certain formulae showing promising sustained-release profiles were subjected to film coating with 15% w/v EC in dichloromethane/ethanol mixture (1:1 ratio) using 1% w/v HPMC as pore former and 30% w/w dibutyl phthalate as plasticizer. The optimized formulations were investigated for drug-excipient compatibility using FTIR and DSC studies. Physical evaluation of the prepared tablets fulfilled the pharmacopoeial requirements for tablet friability test, where the weight loss of the prepared formulae did not exceed 1% of the weight of the tested tablets. Moderate release was obtained from tablets containing HPMC. FTIR and DSC studies for such formulae revealed the absence of any type of chemical interaction between venlafaxine HCl and the used polymers or excipients. Forced swimming test in rats was used to evaluate the antidepressant activity of the selected matrix tablets of venlafaxine HCl. Results showed that formulations significantly decreased the duration of animals’ immobility during the 24 hr-period of the test compared to non-treated group.

Keywords: antidepressant, sustained-release, matrix tablet, venlafaxine hydrochloride

Procedia PDF Downloads 201
1129 The Interplay of Dietary Fibers and Intestinal Microbiota Affects Type 2 Diabetes by Generating Short-Chain Fatty Acids

Authors: Muhammad Mazhar, Yong Zhu, Likang Qin

Abstract:

Foods contain endogenous components known as dietary fibers, which are classified into soluble and insoluble forms. Dietary fibers are resistant to gut digestive enzymes, modulating anaerobic intestinal microbiota (AIM) and fabricating short-chain fatty acids (SCFAs). Acetate, butyrate, and propionate dominate in the gut, and different pathways, including Wood-Ljungdahl and acrylate pathways, generate these SCFAs. In pancreatic dysfunction, the release of insulin/glucagon is impaired, which leads to hyperglycemia. SCFAs enhance insulin sensitivity or secretion, beta-cell functions, leptin release, mitochondrial functions, and intestinal gluconeogenesis in human organs, which positively affect type 2 diabetes (T2D). Research models presented that SCFAs either enhance the release of peptide YY (PYY) and glucagon-like peptide-1 (GLP-1) from L-cells (entero-endocrine) or promote the release of leptin hormone satiation in adipose tissues through G-protein receptors, i.e., GPR-41/GPR-43. Dietary fibers are the components of foods that influence AIM and produce SCFAs, which may be offering beneficial effects on T2D. This review addresses the effectiveness of SCFAs in modulating gut AIM in the fermentation of dietary fiber and their worth against T2D.

Keywords: dietary fibers, intestinal microbiota, short-chain fatty acids, fermentation, type 2 diabetes

Procedia PDF Downloads 39
1128 Biodistribution of Fluorescence-Labelled Epidermal Growth Factor Protein from Slow Release Nanozolid Depots in Mouse

Authors: Stefan Gruden, Charlott Brunmark, Bo Holmqvist, Erwin D. Brenndorfer, Martin Johansson, Jian Liu, Ying Zhao, Niklas Axen, Moustapha Hassan

Abstract:

Aim: The study was designed to evaluate the ability of the calcium sulfate-based NanoZolid® drug delivery technology to locally release the epidermal growth factor (EGF) protein while maintaining its biological activity. Methods: NanoZolid-formulated EGF protein labelled with a near-infrared dye (EGF-NIR) depots or EGF-NIR dissolved in PBS were injected subcutaneously into mice bearing EGF receptor (EGFR) positive human A549 lung cancer tumors inoculated subcutaneously. The release and biodistribution of the EGF-NIR were investigated in vivo longitudinally up to 96 hours post-administration, utilizing whole-body fluorescence imaging. In order to confirm the in vivo findings, histological analysis of tumor cryosections was performed to investigate EGF-NIR fluorescent signal and EGFR expression level by immunofluorescence labelling. Results: The in vivo fluorescence imaging showed a controlled release profile of the EGF-NIR loaded in the NanoZolid depots compared to free EGF-NIR. Histological analysis of the tumors further demonstrated a prevailing distribution of EGF-NIR in regions with high levels of EGFR expression. Conclusion: Calcium sulfate based depots can be used to formulate EGF while maintaining its biological activity, e.g., receptor binding capability. This may have good clinical potential for local delivery of biomolecules to enhance treatment efficacy and minimize systemic adverse effects.

Keywords: bioresorbable, calcium sulfate, controlled release, NanoZolid

Procedia PDF Downloads 133
1127 Mobulid Ray Post-Release Mortality to Assess the Feasibility of Live-Release Management Measures

Authors: Sila K. Sari, Betty J.L. Laglbauer, Muhammad G. Salim, Irianies C. Gozali, Iqbal Herwata, Fahmi Fahmi, Selvia Oktaviyani, Isabel Ender, Sarah Lewis, Abraham Sianipar, Mark Erdmann

Abstract:

Taking strides towards the sustainable use of marine stocks requires science-based management of target fish populations and reduction of bycatch in non-selective fisheries. Among elasmobranchs, mobulid rays are faced with high extinction risk due to intrinsic vulnerability to fishing and their conservation has been recognized as a strong priority both in Indonesia and worldwide. Despite their common vulnerabilities to fishing pressure due to slow growth, late maturation and low fecundity, only manta rays, but not devil rays, are protected in Indonesian waters. However, both manta and devil rays are captured in non-selective fisheries, in particular drift gillnets, since their habitat overlaps with fishing grounds for primary target species (e.g. marlin, swordfish and bullet tuna off the coast of Muncar). For this reason, mobulid populations are being heavily impacted, and while national-level protections are crucial to help conservation, they may not suffice alone to insure populations sustainability. In order to assess the potential of applying live-release management measures to conserve mobulids captured as bycatch in drift gillnets, we deployed pop-up survival archival transmitters to assess post-release mortality in Indonesian mobulid rays. We also assessed which fishing practices, in particular, soak duration, affected post-release mortality in order to draw relevant conclusions for management.

Keywords: Mobulid, Devil ray, Manta ray, Bycatch

Procedia PDF Downloads 138
1126 Preparation of Bead-On-String Alginate/Soy Protein Isolated Nanofibers via Water-Based Electrospinning and Its Application for Drug Loading

Authors: Patcharakamon Nooeaid, Piyachat Chuysrinuan

Abstract:

Electrospun natural polymers-based nanofibers are one of the most interesting materials used in tissue engineering and drug delivery applications. Bead-on-string nanofibers have gained considerable interest for sustained drug release. Vancomycin was used as the model drug and sodium alginate (SA)/soy protein isolated (SPI) as the polymer blend to fabricate the bead-on-string nanofibers by aqueous-based electrospinning. The bead-on-string SA/SPI nanofibers were successfully fabricated by the addition of poly(ethylene oxide) (PEO) as a co-blending polymer. SA-PEO with mass ratio of 70/30 showed the best spinnability with continuous nanofibers without the occurrence of beads. Bead structure formed with the addition of SPI and bead number increased with increasing SPI content. The electrospinning of 80/20 SA-PEO/SPI was obtained as a great promising bead-on-string nanofibers for drug loading, while the solution of 50/50 was not able to obtain continuous fibers. In vitro release tests showed that a more sustainable release profile up to 14 days with less initial burst release on day 1 could be obtained from the bead-on-string fibers than from smooth fibers with uniform diameter. In addition, vancomycin-loaded beaded fibers inhibited the growth of Staphylococcus aureus (S. aureus) bacteria. Therefore, the SA-PEO/SPI nanofibers showed the potential to be used as biomaterials for tissue engineering and drug delivery.

Keywords: bead-on-string fibers, electrospinning, drug delivery, tissue engineering

Procedia PDF Downloads 306
1125 Solid Lipid Nanoparticles of Levamisole Hydrochloride

Authors: Surendra Agrawal, Pravina Gurjar, Supriya Bhide, Ram Gaud

Abstract:

Levamisole hydrochloride is a prominent anticancer drug in the treatment of colon cancer but resulted in toxic effects due poor bioavailability and poor cellular uptake by tumor cells. Levamisole is an unstable drug. Incorporation of this molecule in solid lipids may minimize their exposure to the aqueous environment and partly immobilize the drug molecules within the lipid matrix-both of which may protect the encapsulated drugs against degradation. The objectives of the study were to enhance bioavailability by sustaining drug release and to reduce the toxicities associated with the therapy. Solubility of the drug was determined in different lipids to select the components of Solid Lipid Nanoparticles (SLN). Pseudoternary phase diagrams were created using aqueous titration method. Formulations were subjected to particle size and stability evaluation to select the final test formulations which were characterized for average particle size, zeta potential, and in-vitro drug release and percentage transmittance to optimize the final formulation. SLN of Levamisole hydrochloride was prepared by Nanoprecipitation method. Glyceryl behenate (Compritol 888 ATO) was used as core comprising of Tween 80 as surfactant and Lecithin as co-surfactant in (1:1) ratio. Entrapment efficiency (EE) was found to be 45.89%. Particle size was found in the range of 100-600 nm. Zeta potential of the formulation was -17.0 mV revealing the stability of the product. In-vitro release study showed that 66 % drug released in 24 hours in pH 7.2 which represent that formulation can give controlled action at the intestinal environment. In pH 5.0 it showed 64% release indicating that it can even release drug in acidic environment of tumor cells. In conclusion, results revealed SLN to be a promising approach to sustain the drug release so as to increase bioavailability and cellular uptake of the drug with reduction in toxic effects as dose has been reduced with controlled delivery.

Keywords: SLN, nanoparticulate delivery of levamisole, pharmacy, pharmaceutical sciences

Procedia PDF Downloads 403
1124 Sun Protection Factor (SPF) Determination of Sericin Cream and Niosomal Gel

Authors: Farzad Doostishoar, Abbas Pardakhty, Abdolreza Hassanzadeh, Sudeh salarpour, Elham Sharif

Abstract:

Background: Sericin is a protein extracted from silk and has antioxidant, antimicrobial, antineoplastic, wound healing and moisturizing properties. Different cosmetic formulation of sericin is available in different countries such as Japan and the other south-eastern Asian countries. We formulated and evaluated the sunscreen properties of topical formulations of sericin by an in vitro method. Method: Niosomes composed of sorbitan palmitate (Span 40), polysorbate 40 (Tween 40) and cholesterol (300 µmol, 3.5:3.5:3 molar ratio) were prepared by film hydration technique. Sericin was dissolved in normal saline and the lipid hydration was carried out at 60°C and the niosomes were incorporated in a Carbomer gel base. A W/O cream was also prepared and the release of sericin was evaluated by using Franz diffusion cell. Particle size analysis, sericin encapsulation efficiency measurement, morphological studies and stability evaluation were done in niosomal formulations. SPF was calculated by using Transpore tape in vitro method for both formulations. Results: Niosomes had high stability during 6 months storage at 4-8°C. The mean volume diameter of niosomes was less than 7 µm which is ideal for sustained release of drugs in topical formulations. The SPF of niosomal gel was 25 and higher than sericin cream with a diffusion based release pattern of active material. Conclusion: Sericin can be successfully entrapped in niosomes with sustained release pattern and relatively high SPF.

Keywords: sericin, niosomes, sun protection factor, cream, gel

Procedia PDF Downloads 469
1123 Cellular Uptake and Endocytosis of Doxorubicin Loaded Methoxy Poly (Ethylene Glycol)-Block-Poly (Glutamic Acid) [DOX/mPEG-b-PLG] Nanoparticles against Human Breast Cancer Cell Lines

Authors: Zaheer Ahmad, Afzal Shah

Abstract:

pH responsive block copolymers consist of mPEG and glutamic acid units were syntheiszed in different formulations. The synthesized polymers were structurally investigated. Doxorubicin Hydrocholide (DOX-HCl) as a chemotherapy medication for the treatment of cancer was selected. DOX-HCl was loaded and their drug loading content and drug loading efficiency were determined. The nanocarriers were obtained in small size, well shaped and slightly negative surface charge. The release study was carried out both at pH 7.4 and 5.5 and it was revealed that the release was sustained and in controlled manner and there was no initial burst release. The in vitro release study was further carried out for different formulations with different glutamic acid moieties. Time dependent cell proliferation inhibition of the free drug and drug loaded nanoparticles against human breast cancer cell lines MCF-7 and Zr-75-30 was observed. Cellular uptakes and endocytosis were investigated by confocal laser scanning microscopy (CLSM) and flow cytometery. The biocompatibility, optimum size, shape and surface charge of the developed nanoparticles make the nanoparticles an efficient drug delivery carrier.

Keywords: doxorubicin, glutamic acid, cell proliferation inhibition, breast cancer cell

Procedia PDF Downloads 99
1122 Formulation Development and Evaluation of Floating Tablets of Venlafaxine Hydrochloride

Authors: Gajera Lalit, Shah Pranav, Shah Shailesh

Abstract:

Venlafaxine hydrochloride has a short elimination half-life of 5 ± 2 hr, and absorption window in the upper part of gastrointestinal tract. The conventional tablets need to be administered two to three times a day and possess an oral bioavailability of 45%. The purpose of this study was to formulate gastroretentive effervescent floating tablets of Venlafaxine HCl. Different grades of HPMC namely K15M, K4M, K100M and E15LV were employed as swelling polymers whereas sodium bicarbonate was employed as gas generating agent. The direct compression method was employed for the formulation of tablets. The tablets were evaluated in terms of hardness, friability, weight variation, drug content, water uptake, in-vitro floating behavior and in-vitro drug release study. All the formulations exhibited very short floating lag time of < 1 min and total floating time of 12 hr. Formulation L3 containing 25 mg and 75 mg of HPMC E15 LV and HPMC K15M respectively exhibited complete drug release within 12 hrs.

Keywords: venlafaxine HCl, hydroxyl propyl methylcellulose, floating gastro retentive tablets, in-vitro drug release, non-fickian diffusion

Procedia PDF Downloads 508
1121 Energy Production with Closed Methods

Authors: Bujar Ismaili, Bahti Ismajli, Venhar Ismaili, Skender Ramadani

Abstract:

In Kosovo, the problem with the electricity supply is huge and does not meet the demands of consumers. Older thermal power plants, which are regarded as big environmental polluters, produce most of the energy. Our experiment is based on the production of electricity using the closed method that does not affect environmental pollution by using waste as fuel that is considered to pollute the environment. The experiment was carried out in the village of Godanc, municipality of Shtime - Kosovo. In the experiment, a production line based on the production of electricity and central heating was designed at the same time. The results are the benefits of electricity as well as the release of temperature for heating with minimal expenses and with the release of 0% gases into the atmosphere. During this experiment, coal, plastic, waste from wood processing, and agricultural wastes were used as raw materials. The method utilized in the experiment allows for the release of gas through pipes and filters during the top-to-bottom combustion of the raw material in the boiler, followed by the method of gas filtration from waste wood processing (sawdust). During this process, the final product is obtained - gas, which passes through the carburetor, which enables the gas combustion process and puts into operation the internal combustion machine and the generator and produces electricity that does not release gases into the atmosphere. The obtained results show that the system provides energy stability without environmental pollution from toxic substances and waste, as well as with low production costs. From the final results, it follows that: in the case of using coal fuel, we have benefited from more electricity and higher temperature release, followed by plastic waste, which also gave good results. The results obtained during these experiments prove that the current problems of lack of electricity and heating can be met at a lower cost and have a clean environment and waste management.

Keywords: energy, heating, atmosphere, waste, gasification

Procedia PDF Downloads 201
1120 Sol-Gel Coated Fabric for Controlled Release of Mosquito Repellent

Authors: Bhaskar M. Murai, Neeraj Banchor, Ishveen Chabbra, Madhusudhan Nadgir, S. Vidhya

Abstract:

Sol-gel technology combined with electronics and biochemistry helps to overcome the problems caused by mosquitoes by developing a portable, low-cost device which enables controlled release of trapped compound inside it. It is a wet-chemical technique which is used primarily for fabrication of silicate gel which is usually allowed to dry as per requirement. The outcome is solid rock hard material which is porous and has lots of applications in different fields. Taking porosity as a key factor, allethrin a naturally occurring synthetic compound with molecular mass 302.40 was entrapped inside the sol-gel matrix as a dopant. Allethrin is commonly used as an insecticide and is a key ingredient in commercially available mosquitoes repellent in Asian and subtropical countries. It has low toxicity for humans and birds, and are used in many household insecticides such as RAID as well as mosquito coils. They are however highly toxic to fish and bees. Insects subject to its exposure become paralyzed (nervous system effect) before dying. They are also used as an ultra-low volume spray for outdoor mosquito control. Therefore, there is a need for controlled release of allethrin in the environment. For controlled release of allethrin from sol-gel matrix, its (allethrin) we utilized temperature based controlled evaporation through porous sol-gel. Different types of fabric like cotton, Terri-cotton, polyester, surgical cap, knee-cap etc are studied and the best with maximum absorption capacity is selected to hold the sol-gel matrix with maximum quantity. For sol-gel coating 2 x 2cm cloth pieces are dipped in sol-gel solution for 10 minutes and by calculating the weight difference we concluded that Terri cotton is best suitable for our project. An electronic circuit with heating plate is developed in to test the controlled release of compound. An oscillatory circuit is used to produce the required heat.

Keywords: sol-gel, allethrin, TEOS, biochemistry

Procedia PDF Downloads 345
1119 Multiparticulate SR Formulation of Dexketoprofen Trometamol by Wurster Coating Technique

Authors: Bhupendra G. Prajapati, Alpesh R. Patel

Abstract:

The aim of this research work is to develop sustained release multi-particulates dosage form of Dexketoprofen trometamol, which is the pharmacologically active isomer of ketoprofen. The objective is to utilization of active enantiomer with minimal dose and administration frequency, extended release multi-particulates dosage form development for better patience compliance was explored. Drug loaded and sustained release coated pellets were prepared by fluidized bed coating principle by wurster coater. Microcrystalline cellulose as core pellets, povidone as binder and talc as anti-tacking agents were selected during drug loading while Kollicoat SR 30D as sustained release polymer, triethyl citrate as plasticizer and micronized talc as an anti-adherent were used in sustained release coating. Binder optimization trial in drug loading showed that there was increase in process efficiency with increase in the binder concentration. 5 and 7.5%w/w concentration of Povidone K30 with respect to drug amount gave more than 90% process efficiency while higher amount of rejects (agglomerates) were observed for drug layering trial batch taken with 7.5% binder. So for drug loading, optimum Povidone concentration was selected as 5% of drug substance quantity since this trial had good process feasibility and good adhesion of the drug onto the MCC pellets. 2% w/w concentration of talc with respect to total drug layering solid mass shows better anti-tacking property to remove unnecessary static charge as well as agglomeration generation during spraying process. Optimized drug loaded pellets were coated for sustained release coating from 16 to 28% w/w coating to get desired drug release profile and results suggested that 22% w/w coating weight gain is necessary to get the required drug release profile. Three critical process parameters of Wurster coating for sustained release were further statistically optimized for desired quality target product profile attributes like agglomerates formation, process efficiency, and drug release profile using central composite design (CCD) by Minitab software. Results show that derived design space consisting 1.0 to 1.2 bar atomization air pressure, 7.8 to 10.0 gm/min spray rate and 29-34°C product bed temperature gave pre-defined drug product quality attributes. Scanning Image microscopy study results were also dictate that optimized batch pellets had very narrow particle size distribution and smooth surface which were ideal properties for reproducible drug release profile. The study also focused on optimized dexketoprofen trometamol pellets formulation retain its quality attributes while administering with common vehicle, a liquid (water) or semisolid food (apple sauce). Conclusion: Sustained release multi-particulates were successfully developed for dexketoprofen trometamol which may be useful to improve acceptability and palatability of a dosage form for better patient compliance.

Keywords: dexketoprofen trometamol, pellets, fluid bed technology, central composite design

Procedia PDF Downloads 109
1118 Effect of Therapeutic Exercises with or without Positional Release Technique in Treatment of Chronic Mechanical Low Back Pain Patients a Randomized Controlled Trial

Authors: Ghada M. R. Koura, Mohamed N. Mohamed, Ahmed M. F. El Shiwi

Abstract:

Chronic mechanical Low back dysfunction (CMLBD) is the most common problem of the working-age population in modern industrial sociaty; it causes a substantial economic burden due to the wide use of medical services and absence from work. Aim of work: the aim of this study was to investigate the effect of positional release technique on patients with chronic mechanical low back pain. Materials and Methods: Thirty two patients from both sexes were diagnosed with CMLBP, aged 20 to 45 years and were divided randomly into two equal groups; sixteen patients each; group A (control group) received therapeutic exercises that include (Stretch and Strength exercises for back and abdominal muscles). Group B (experimental group) received therapeutic exercises with positional release technique; treatment was applied 3 days/week for 4 weeks. Pain was measured by Visual Analogue Scale, Lumbar range of motion was measured by Inclinometer and Functional disability was measured by Oswestry disability scale. Measurements were taken at two intervals pre-treatment and post-treatment. Results: Data obtained was analyzed via paired and unpaired t-Test. There were statistical differences between the 2 groups, where the experimental group showed greater improvement than control group. Conclusion: Positional release technique is considered as an effective treatment for reducing pain, functional disability and increasing lumbar range of motion in individuals with chronic mechanical low back pain.

Keywords: chronic mechanical low back pain, traditional physical therapy program, positional release technique, randomized controlled trial

Procedia PDF Downloads 566
1117 Ceramide-PLGA Nanoparticle Formation to Apply to Atopic Dermatitis

Authors: Sang-Myung Jung, Gwang Heum Yoon, Hoo Chul Lee, Hwa Sung Shin

Abstract:

Ceramide, a component of stratum corneum at epidermis, helps to construct a rigid and dense skin barrier to prevent pathogens that cause atopic dermatitis. However, ceramide was too hydrophobic to be directly absorbed into stratum corneum and has risks of side effects by excessive treatment. To overcome the obstacles, ceramide was embedded into PLGA nanoparticles coated with chitosan. PLGA and chitosan have been known as biocompatible materials. PLGA was squeezed when faced with water and pumped ceramide out of PLGA nanoparticle. In addition, the chitosan coating layer helped initial adherence of nanoparticles to skin and regulate ceramide release until removed. This coating was degraded at weakly acid state like skin surface, finally ceramide release could be controlled. Finally, the nanoparticle was demonstrated to be non-cytotoxic and regenerate stratum corneum of atopic dermatitis model. Overall the nanoparticle is suggested as a novel and effective nanodrug to apply atopic dermatitis.

Keywords: nanoparticle, controlled release, atopic dermatitis, chitosan coating, ceramide

Procedia PDF Downloads 367
1116 Influence of Cobalt Incorporation on the Structure and Properties of SOL-Gel Derived Mesoporous Bioglass Nanoparticles

Authors: Ahmed El-Fiqi, Hae-Won Kim

Abstract:

Incorporation of therapeutic elements such as Sr, Cu and Co into bioglass structure and their release as ions is considered as one of the promising approaches to enhance cellular responses, e.g., osteogenesis and angiogenesis. Here, cobalt as angiogenesis promoter has been incorporated (at 0, 1 and 4 mol%) into sol-gel derived calcium silicate mesoporous bioglass nanoparticles. The composition and structure of cobalt-free (CFN) and cobalt-doped (CDN) mesoporous bioglass nanoparticles have been analyzed by X-ray fluorescence (XRF), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and Fourier-Transform Infra-red spectroscopy (FT-IR). The physicochemical properties of CFN and CDN have been investigated using high-resolution transmission electron microscopy (HR-TEM), Selected area electron diffraction (SAED), and Energy-dispersive X-ray (EDX). Furthermore, the textural properties, including specific surface area, pore-volume, and pore size, have been analyzed from N²⁻sorption analyses. Surface charges of CFN and CDN were also determined from surface zeta potential measurements. The release of ions, including Co²⁺, Ca²⁺, and SiO₄⁴⁻ has been analyzed using inductively coupled plasma atomic emission spectrometry (ICP-AES). Loading and release of diclofenac as an anti-inflammatory drug model were explored in vitro using Ultraviolet-visible spectroscopy (UV-Vis). XRD results ensured the amorphous state of CFN and CDN whereas, XRF further confirmed that their chemical compositions are very close to the designed compositions. HR-TEM analyses unveiled nanoparticles with spherical morphologies, highly mesoporous textures, and sizes in the range of 90 - 100 nm. Moreover, N²⁻ sorption analyses revealed that the nanoparticles have pores with sizes of 3.2 - 2.6 nm, pore volumes of 0.41 - 0.35 cc/g and highly surface areas in the range of 716 - 830 m²/g. High-resolution XPS analysis of Co 2p core level provided structural information about Co atomic environment and it confirmed the electronic state of Co in the glass matrix. ICP-AES analysis showed the release of therapeutic doses of Co²⁺ ions from 4% CDN up to 100 ppm within 14 days. Finally, diclofenac loading and release have ensured the drug/ion co-delivery capability of 4% CDN.

Keywords: mesoporous bioactive glass, nanoparticles, cobalt ions, release

Procedia PDF Downloads 83
1115 Resin-coated Controlled Release Fertilizer (CRF) for Oil Palm: Laboratory and Main Nursery Evaluation

Authors: Umar Adli Amran, Tan Choon Chek, Mohd Shahkhirat Norizan, Then Kek Hoe

Abstract:

Controlled release fertilizer (CRF) enables a regulated nutrients release for more efficient plant uptake compared to the normal granular fertilizer. It reduces nutrients loss via surface run-off and leaching, hence promotes sustainable agriculture. Although the performance of CRF in providing consistent and timely nutrients supply is well known, its expensive price limits it usage in a large scale plantation. This study is conducted to evaluate the properties and performance of bio-based polyurethane (PU)-coated CRF via laboratory and oil palm main nursery trial. The CRF is produced by coating of a normal commercial compound granular fertilizer from FGV Fertiliser Sdn. Bhd., namely Felda 10 (10.5-8-20-3+0.5B), and designated as CRF FGV10. Based on laboratory evaluation, the CRF FGV10 can sustain nutrients release for more than 6 months. Vegetative growth parameters such as girth size, palm height, third frond length, and the total number of fronds produced were recorded. Besides that, dry biomass of the oil palm seedlings was also determined. From the evaluation, it is proved that at 50% reduction of nutrients application rate and for only two times application (T3), CRF FGV10 enabled the oil palm seedlings to achieve similar vegetative growth with the control samples (T1). It is also proven that only PU-coated CRF FGV10 had allowed the reduction of fertilizer rate and application rounds.

Keywords: nutrition, oil palm seedlings, polyurethane, sustainable manuring, vegetative growth

Procedia PDF Downloads 15
1114 Improving Software Technology to Support Release Process in Global Software Development Environment: An Experience Report

Authors: Hualter Barbosa, Bruno Bonifacio

Abstract:

The process of globalization and new business has transformed the dynamics of software development. To meet the new demands, the software industry has adapted new methodologies that can shorten development cycles to ensure greater competitiveness. Given this scenario, Global Software Development (GSD) has become a strategic element for new products' success. However, the reliability, opportunity, and perceived value can be influenced substantially with the automation of steps in the development process activities. In this sense, the development of new technologies can help developers and managers to improve the quality of development. This paper presents a report on improving one of the release process activities of Sidia's mobile product area using software technology. The objective is to present the improvement of the CLCATCH tool developed based on experimental studies and qualitative analysis on the points of improvement for the release process in Android update projects for Samsung mobile devices. The results show improvement for the new version and approach of the tool, with points that can facilitate new features of the proposed technology.

Keywords: Android updated, empirical studies, GSD, process improvement

Procedia PDF Downloads 117
1113 Everolimus Loaded Polyvinyl Alcohol Microspheres for Sustained Drug Delivery in the Treatment of Subependymal Giant Cell Astrocytoma

Authors: Lynn Louis, Bor Shin Chee, Marion McAfee, Michael Nugent

Abstract:

This article aims to develop a sustained release formulation of microspheres containing the mTOR inhibitor Everolimus (EVR) using Polyvinyl alcohol (PVA) to enhance the bioavailability of the drug and to overcome poor solubility characteristics of Everolimus. This paper builds on recent work in the manufacture of microspheres using the sessile droplet technique by freezing the polymer-drug solution by suspending the droplets into pre-cooled ethanol vials immersed in liquid nitrogen. The spheres were subjected to 6 freezing cycles and 3 freezing cycles with thawing to obtain proper geometry, prevent aggregation, and achieve physical cross-linking. The prepared microspheres were characterised for surface morphology by SEM, where a 3-D porous structure was observed. The in vitro release studies showed a 62.17% release over 12.5 days, indicating a sustained release due to good encapsulation. This result is comparatively much more than the 49.06% release achieved within 4 hours from the solvent cast Everolimus film as a control with no freeze-thaw cycles performed. The solvent cast films were made in this work for comparison. A prolonged release of Everolimus using a polymer-based drug delivery system is essential to reach optimal therapeutic concentrations in treating SEGA tumours without systemic exposure. These results suggest that the combination of PVA and Everolimus via a rheological synergism enhanced the bioavailability of the hydrophobic drug Everolimus. Physical-chemical characterisation using DSC and FTIR analysis showed compatibility of the drug with the polymer, and the stability of the drug was maintained owing to the high molecular weight of the PVA. The obtained results indicate that the developed PVA/EVR microsphere is highly suitable as a potential drug delivery system with improved bioavailability in treating Subependymal Giant cell astrocytoma (SEGA).

Keywords: drug delivery system, everolimus, freeze-thaw cycles, polyvinyl alcohol

Procedia PDF Downloads 83
1112 A Study on the Synthetic Resin of Fire Risk Using the Room Corner Test

Authors: Ji Hun Choi, Seung Un Chae, Kyeong Suk Cho

Abstract:

Synthetic resins are widely used in various fields including electricity, engineering, construction and agriculture. Many of interior and exterior finishing materials for buildings are synthetic resin products. In this study, full-scale fire tests were conducted on polyvinyl chloride, polypropylene and urethane in accordance with the “ISO 9705: Fire test - Full-scale room test for surface products” to measure heat release rate, toxic gas emission and smoke production rate. Based on the tests, fire growth pattern and fire risk were analyzed. Findings from the tests conducted on polyvinyl chloride and urethane are as follows. The total heat release rate and total smoke production rate of polyvinyl chloride were 98.89MW and 5284.41m2, respectively and its highest CO2 concentration was 0.149%. The values obtained from the test with urethane were 469.94 MW, 3396.28 m2 and 1.549%. While heat release rate and CO2 concentration were higher in urethane implying its high combustibility, smoke production rate was 1.5 times higher in polyvinyl chloride. Follow-up tests are planned to be conducted to accumulate data for the evaluation of heat emission and fire risk associated with synthetic resins.

Keywords: synthetic resins, fire test, full-scale test, heat release rate, smoke production rate, polyvinyl chloride, polypropylene, urethane

Procedia PDF Downloads 400
1111 An Activatable Prodrug for the Treatment of Metastatic Tumors

Authors: Eun-Joong Kim, Sankarprasad Bhuniya, Hyunseung Lee, Hyun Min Kim, Chaejoon Cheong, Su-khendu Maiti, Kwan Soo Hong, Jong Seung Kim

Abstract:

Metastatic cancers have historically been difficult to treat. However, metastatic tumors have been found to have high levels of reactive oxygen species such as hydrogen peroxide (H2O2), supporting the hypothesis that a prodrug could be activated by intracellular H2O2 and lead to a potential anti-metastatic therapy. In this study, prodrug 7 was designed to be activated by H2O2-mediated boronate oxidation, resulting in activation of the fluorophore for detection and release of the therapeutic agent, SN-38. Drug release from prodrug 7 was investigated by monitoring fluorescence after addition of H2O2 to the cancer cells. Prodrug 7 activated by H2O2 selectively inhibited tumor cell growth. Furthermore, intratracheally administered prodrug 7 showed effective anti-tumor activity in a mouse model of metastatic lung disease. Thus, this H2O2-responsive prodrug has therapeutic potential as a novel treatment for metastatic cancer via cellular imaging with fluorescence as well as selective release of the anti-cancer drug, SN-38.

Keywords: hydrogen peroxide, prodrug, metastatic tumors, fluorescence

Procedia PDF Downloads 423
1110 Synthesis and Characterization of Polycaprolactone for the Delivery of Rifampicin

Authors: Evelyn Osehontue Uroro, Richard Bright, Jing Yang Quek, Krasimir Vasilev

Abstract:

Bacterial infections have been a challenge both in the public and private sectors. The colonization of bacteria often occurs in medical devices such as catheters, heart valves, respirators, and orthopaedic implants. When biomedical devices are inserted into patients, the deposition of macromolecules such as fibrinogen and immunoglobin on their surfaces makes it easier for them to be prone to bacteria colonization leading to the formation of biofilms. The formation of biofilms on medical devices has led to a series of device-related infections which are usually difficult to eradicate and sometimes cause the death of patients. These infections require surgical replacements along with prolonged antibiotic therapy, which would incur additional health costs. It is, therefore, necessary to prevent device-related infections by inhibiting the formation of biofilms using intelligent technology. Antibiotic resistance of bacteria is also a major threat due to overuse. Different antimicrobial agents have been applied to microbial infections. They include conventional antibiotics like rifampicin. The use of conventional antibiotics like rifampicin has raised concerns as some have been found to have hepatic and nephrotoxic effects due to overuse. Hence, there is also a need for proper delivery of these antibiotics. Different techniques have been developed to encapsulate and slowly release antimicrobial agents, thus reducing host cytotoxicity. Examples of delivery systems are solid lipid nanoparticles, hydrogels, micelles, and polymeric nanoparticles. The different ways by which drugs are released from polymeric nanoparticles include diffusion-based release, elution-based release, and chemical/stimuli-responsive release. Polymeric nanoparticles have gained a lot of research interest as they are basically made from biodegradable polymers. An example of such a biodegradable polymer is polycaprolactone (PCL). PCL degrades slowly by hydrolysis but is often sensitive and responsive to stimuli like enzymes to release encapsulants for antimicrobial therapy. This study presents the synthesis of PCL nanoparticles loaded with rifampicin and the on-demand release of rifampicin for treating staphylococcus aureus infections.

Keywords: enzyme, Staphylococcus aureus, PCL, rifampicin

Procedia PDF Downloads 73
1109 An Efficient Hybrid Feedstock Pretreatment Technique for the Release of Fermentable Sugar from Cassava Peels for Biofuel Production

Authors: Gabriel Sanjo Aruwajoye, E. B. Gueguim Kana

Abstract:

Agricultural residues present a low-cost feedstock for bioenergy production around the world. Cassava peels waste are rich in organic molecules that can be readily converted to value added products such as biomaterials and biofuels. However, due to the presence of high proportion of structural carbohydrates and lignin, the hydrolysis of this feedstock is imperative to achieve maximum substrate utilization and energy yield. This study model and optimises the release of Fermentable Sugar (FS) from cassava peels waste using the Response Surface Methodology. The investigated pretreatment input parameters consisted of soaking temperature (oC), soaking time (hours), autoclave duration (minutes), acid concentration (% v/v), substrate solid loading (% w/v) within the range of 30 to 70, 0 to 24, 5 to 20, 0 to 5 and 2 to 10 respectively. The Box-Behnken design was used to generate 46 experimental runs which were investigated for FS release. The obtained data were used to fit a quadratic model. A coefficient of determination of 0.87 and F value of 8.73 was obtained indicating the good fitness of the model. The predicted optimum pretreatment conditions were 69.62 oC soaking temperature, 2.57 hours soaking duration, 5 minutes autoclave duration, 3.68 % v/v HCl and 9.65 % w/v solid loading corresponding to FS yield of 91.83g/l (0.92 g/g cassava peels) thus 58% improvement on the non-optimised pretreatment. Our findings demonstrate an efficient pretreatment model for fermentable sugar release from cassava peels waste for various bioprocesses.

Keywords: feedstock pretreatment, cassava peels, fermentable sugar, response surface methodology

Procedia PDF Downloads 331
1108 Sphingosomes: Potential Anti-Cancer Vectors for the Delivery of Doxorubicin

Authors: Brajesh Tiwari, Yuvraj Dangi, Abhishek Jain, Ashok Jain

Abstract:

The purpose of the investigation was to evaluate the potential of sphingosomes as nanoscale drug delivery units for site-specific delivery of anti-cancer agents. Doxorubicin Hydrochloride (DOX) was selected as a model anti-cancer agent. Sphingosomes were prepared and loaded with DOX and optimized for size and drug loading. The formulations were characterized by Malvern zeta-seizer and Transmission Electron Microscopy (TEM) studies. Sphingosomal formulations were further evaluated for in-vitro drug release study under various pH profiles. The in-vitro drug release study showed an initial rapid release of the drug followed by a slow controlled release. In vivo studies of optimized formulations and free drug were performed on albino rats for comparison of drug plasma concentration. The in- vivo study revealed that the prepared system enabled DOX to have had enhanced circulation time, longer half-life and lower elimination rate kinetics as compared to free drug. Further, it can be interpreted that the formulation would selectively enter highly porous mass of tumor cells and at the same time spare normal tissues. To summarize, the use of sphingosomes as carriers of anti-cancer drugs may prove to be a fascinating approach that would selectively localize in the tumor mass, increasing the therapeutic margin of safety while reducing the side effects associated with anti-cancer agents.

Keywords: sphingosomes, anti-cancer, doxorubicin, formulation

Procedia PDF Downloads 275
1107 3D Biomechanical Analysis in Shot Put Techniques of International Throwers

Authors: Satpal Yadav, Ashish Phulkar, Krishna K. Sahu

Abstract:

Aim: The research aims at doing a 3 Dimension biomechanical analysis in the shot put techniques of International throwers to evaluate the performance. Research Method: The researcher adopted the descriptive method and the data was subjected to calculate by using Pearson’s product moment correlation for the correlation of the biomechanical parameters with the performance of shot put throw. In all the analyses, the 5% critical level (p ≤ 0.05) was considered to indicate statistical significance. Research Sample: Eight (N=08) international shot putters using rotational/glide technique in male category was selected as subjects for the study. The researcher used the following methods and tools to obtain reliable measurements the instrument which was used for the purpose of present study namely the tesscorn slow-motion camera, specialized motion analyzer software, 7.260 kg Shot Put (for a male shot-putter) and steel tape. All measurement pertaining to the biomechanical variables was taken by the principal investigator so that data collected for the present study was considered reliable. Results: The finding of the study showed that negative significant relationship between the angular velocity right shoulder, acceleration distance at pre flight (-0.70), (-0.72) respectively were obtained, the angular displacement of knee, angular velocity right shoulder and acceleration distance at flight (0.81), (0.75) and (0.71) respectively were obtained, the angular velocity right shoulder and acceleration distance at transition phase (0.77), (0.79) respectively were obtained and angular displacement of knee, angular velocity right shoulder, release velocity shot, angle of release, height of release, projected distance and measured distance as the values (0.76), (0.77), (-0.83), (-0.79), (-0.77), (0.99) and (1.00) were found higher than the tabulated value at 0.05 level of significance. On the other hand, there exists an insignificant relationship between the performance of shot put and acceleration distance [m], angular displacement shot, C.G at release and horizontal release distance on the technique of shot put.

Keywords: biomechanics, analysis, shot put, international throwers

Procedia PDF Downloads 162
1106 Charged Amphiphilic Polypeptide Based Micelle Hydrogel Composite for Dual Drug Release

Authors: Monika Patel, Kazuaki Matsumura

Abstract:

Synthetic hydrogels, with their unique properties such as porosity, strength, and swelling in aqueous environment, are being used in many fields from food additives to regenerative medicines, from diagnostic and pharmaceuticals to drug delivery systems (DDS). But, hydrogels also have some limitations in terms of homogeneity of drug distribution and quantity of loaded drugs. As an alternate, polymeric micelles are extensively used as DDS. With the ease of self-assembly, and distinct stability they remarkably improve the solubility of hydrophobic drugs. However, presently, combinational therapy is the need of time and so are systems which are capable of releasing more than one drug. And it is one of the major challenges towards DDS to control the release of each drug independently, which simple DDS cannot meet. In this work, we present an amphiphilic polypeptide based micelle hydrogel composite to study the dual drug release for wound healing purposes using Amphotericin B (AmpB) and Curcumin as model drugs. Firstly, two differently charged amphiphilic polypeptide chains were prepared namely, poly L-Lysine-b-poly phenyl alanine (PLL-PPA) and poly Glutamic acid-b-poly phenyl alanine (PGA-PPA) through ring opening polymerization of amino acid N-carboxyanhydride. These polymers readily self-assemble to form micelles with hydrophobic PPA block as core and hydrophilic PLL/PGA as shell with an average diameter of about 280nm. The thus formed micelles were loaded with the model drugs. The PLL-PPA micelle was loaded with curcumin and PGA-PPA was loaded with AmpB by dialysis method. Drug loaded micelles showed a slight increase in the mean diameter and were fairly stable in solution and lyophilized forms. For forming the micelles hydrogel composite, the drug loaded micelles were dissolved and were cross linked using genipin. Genipin uses the free –NH2 groups in the PLL-PPA micelles to form a hydrogel network with free PGA-PPA micelles trapped in between the 3D scaffold formed. Different composites were tested by changing the weight ratios of the both micelles and were seen to alter its resulting surface charge from positive to negative with increase in PGA-PPA ratio. The composites with high surface charge showed a burst release of drug in initial phase, were as the composites with relatively low net charge showed a sustained release. Thus the resultant surface charge of the composite can be tuned to tune its drug release profile. Also, while studying the degree of cross linking among the PLL-PPA particles for effect on dual drug release, it was seen that as the degree of crosslinking increases, an increase in the tendency to burst release the drug (AmpB) is seen in PGA-PPA particle, were as on the contrary the PLL-PPA particles showed a slower release of Curcumin with increasing the cross linking density. Thus, two different pharmacokinetic profile of drugs were seen by changing the cross linking degree. In conclusion, a unique charged amphiphilic polypeptide based micelle hydrogel composite for dual drug delivery. This composite can be finely tuned on the basis of need of drug release profiles by changing simple parameters such as composition, cross linking and pH.

Keywords: amphiphilic polypeptide, dual drug release, micelle hydrogel composite, tunable DDS

Procedia PDF Downloads 178
1105 Pregnant Women with Dental Amalgam Fillings Limiting Their Exposure to Electromagnetic Fields to Prevent the Toxic Effects of Mercury in Their Fetuses

Authors: Ghazal Mortazavi, S. M. J. Mortazavi

Abstract:

Although seems to be ultra-conservative, it has recently been suggested that whenever it is possible, pregnant women should postpone dental amalgam restorations to avoid the toxic effect of mercury on the foetus. Dental amalgam fillings cause significant exposure to elemental mercury vapour in the general population. Over the past several years, our lab has focused on the health effects of exposure of laboratory animals and humans to different sources of electromagnetic fields such as mobile phones and their base stations, mobile phone jammers, laptop computers, radars, dentistry cavitrons and MRI. Today, substantial evidence indicates that mercury even at low doses may lead to toxicity. Increased release of mercury from dental amalgam fillings after exposure to MRI or microwave radiation emitted by mobile phones has been previously shown by our team. Moreover, our recent studies on the effects of stronger magnetic fields entirely confirmed our previous findings. From the other point of view, we have also shown that papers which reported no increased release of mercury after MRI, may have some methodological flaws. As a strong positive correlation between maternal and cord blood mercury levels has been found in some studies, our findings regarding the effect of exposure to electromagnetic fields on the release of mercury from dental amalgam fillings lead us to this conclusion that pregnant women with dental amalgam fillings should limit their exposure to electromagnetic fields to prevent toxic effects of mercury in their foetuses.

Keywords: pregnancy, foetus, mercury release, dental amalgam, electromagnetic fields, MRI, mobile phones

Procedia PDF Downloads 252
1104 Green Approach towards Synthesis of Chitosan Nanoparticles for in vitro Release of Quercetin

Authors: Dipali Nagaonkar, Mahendra Rai

Abstract:

Chitosan, a carbohydrate polymer at nanoscale level has gained considerable momentum in drug delivery applications due to its inherent biocompatibility and non-toxicity. However, conventional synthetic strategies for chitosan nanoparticles mainly rely upon physicochemical techniques, which often yield chitosan microparticles. Hence, there is an emergent need for development of controlled synthetic protocols for chitosan nanoparticles within the nanometer range. In this context, we report the green synthesis of size controlled chitosan nanoparticles by using Pongamia pinnata (L.) leaf extract. Nanoparticle tracking analysis confirmed formation of nanoparticles with mean particle size of 85 nm. The stability of chitosan nanoparticles was investigated by zetasizer analysis, which revealed positive surface charged nanoparticles with zeta potential 20.1 mV. The green synthesized chitosan nanoparticles were further explored for encapsulation and controlled release of antioxidant biomolecule, quercetin. The resulting drug loaded chitosan nanoparticles showed drug entrapment efficiency of 93.50% with drug-loading capacity of 42.44%. The cumulative in vitro drug release up to 15 hrs was achieved suggesting towards efficacy of green synthesized chitosan nanoparticles for drug delivery applications.

Keywords: Chitosan nanoparticles, green synthesis, Pongamia pinnata, quercetin

Procedia PDF Downloads 550
1103 Citrullinated Myelin Basic Protein Mediated Inflammation in Astrocytes

Authors: Lali Shanshiashvili, Marika Chikviladze, Nino Mamulashvili, Maia Sepashvili, Nana Narmania, David Mikeladze

Abstract:

Purpose: During demyelinating inflammatory diseases and after the damage of the myelin sheet, myelin-derived proteins, including myelin basic protein (MBP), are secreted into the extracellular space. MBP shows extensive post-translational modifications, including the deimination of arginine residues. Deiminated MBP is structurally less ordered, susceptible to proteolytic attack, and more immunogenic than the unmodified one. It is hypothesized that MBP could change the inflammatory response in astrocytes. Methods: MBP was isolated and purified from bovine brain white matter. Primary astrocyte cultures were prepared from whole brains of 2-day-old Wistar rats. For evaluation of glutamate uptake/release in astrocytes following treatment of cells with MBP charge isomers, Glutamate Assay Kit was used. The expression of EAAT-2 (excitatory amino acid transporters), peroxisome proliferator-activated receptor gamma (PPAR- γ), inhibitor of nuclear factor kappa B (IkB), and high mobility group protein B1 (HMGB1) in astrocytes were assayed by Western Blot analysis. Results: This study investigated the action of deiminated isomer (C8) on the cultured primary astrocytes and compared its effects with the effects of unmodified C1 isomers. The study found that C8 and C1 MBP differently act on the uptake and release of glutamate in astrocytes: nonmodified C1 MBP increases the uptake of glutamate and does not change the release, whereas C8 decreases the release of glutamate but does not alter the uptake. Nevertheless, both isomers increased the expression of PPAR-γ and EAAT2 in the same intensity. However, immunostaining and Western Blots of cell lysates showed a decrease of IkB and increased expression of HMGB1 after the treatment of astrocytes by C8. Moreover, in the presence of C8, astrocytes release more nitric oxide than unmodified C1 isomers. Conclusion: These data suggest that the deiminated isomer of MBP evokes an inflammatory response and enhances the ability of astrocytes to release proinflammatory mediators through activation of NF-kB after the breakdown of myelin sheets. Acknowledgment: This research was supported by the SRNSF Georgia RF17_534 grant.

Keywords: myelin basic protein, glutamate, deimination, astrocytes, inflammation

Procedia PDF Downloads 174
1102 Formulation of Famotidine Solid Lipid Nanoparticles (SLN): Preparation, Evaluation and Release Study

Authors: Rachmat Mauludin, Nurmazidah

Abstract:

Background and purpose: Famotidine is an H2 receptor blocker. Absorption orally is rapid enough, but famotidine can be degraded by stomach acid causing dose reduction until 35.8% after 50 minutes. This drug also undergoes first-pass metabolism which reduced its bio availability only until 40-50%. To overcome these problems, Solid Lipid Nano particles (SLNs) as alternative delivery systems can be formulated. SLNs is a lipid-based drug delivery technology with 50-1000 nm particle size, where the drug incorporated into the bio compatible lipids and the lipid particles are stabilized using appropriate stabilizers. When the particle size is 200 nm or below, lipid containing famotidine can be absorbed through the lymphatic vessels to the subclavian vein, so first-pass metabolism can be avoided. Method: Famotidine SLNs with various compositions of stabilizer was prepared using a high-speed homogenization and sonication method. Then, the particle size distribution, zeta potential, entrapment efficiency, particle morphology and in vitro release profiles were evaluated. Optimization of sonication time also carried out. Result: Particle size of SLN by Particle Size Analyzer was in range 114.6 up to 455.267 nm. Ultrasonicated SLNs within 5 minutes generated smaller particle size than SLNs which was ultrasonicated for 10 and 15 minutes. Entrapment efficiency of SLNs were 74.17 up to 79.45%. Particle morphology of the SLNs was spherical and distributed individually. Release study of Famotidine revealed that in acid medium, 28.89 up to 80.55% of famotidine could be released after 2 hours. Nevertheless in basic medium, famotidine was released 40.5 up to 86.88% in the same period. Conclusion: The best formula was SLNs which stabilized by 4% Poloxamer 188 and 1 % Span 20, that had particle size 114.6 nm in diameter, 77.14% famotidine entrapped, and the particle morphology was spherical and distributed individually. SLNs with the best drug release profile was SLNs which stabilized by 4% Eudragit L 100-55 and 1% Tween 80 which had released 36.34 % in pH 1.2 solution, and 74.13% in pH 7.4 solution after 2 hours. The optimum sonication time was 5 minutes.

Keywords: famotodine, SLN, high speed homogenization, particle size, release study

Procedia PDF Downloads 826