TY - JFULL AU - Yi-Ping Fang and Hsien-Ting Cheng PY - 2012/7/ TI - 5-Aminolevulinic Acid-Loaded Gel, Sponge Collagen to Enhance the Delivery Ability to Skin T2 - International Journal of Biotechnology and Bioengineering SP - 376 EP - 380 VL - 6 SN - 1307-6892 UR - https://publications.waset.org/pdf/7513 PU - World Academy of Science, Engineering and Technology NX - Open Science Index 66, 2012 N2 - Topical photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is an alternative therapy for treating superficial cancer, especially for skin or oral cancer. ALA, a precursor of the photosensitizer protoporphyrin IX (PpIX), is present as zwitterions and hydrophilic property which make the low permeability through the cell membrane. Collagen is a traditional carrier; its molecular composed various amino acids which bear positive charge and negative charge. In order to utilize the ion-pairs with ALA and collagen, the study employed various pH values adjusting the net charge. The aim of this study was to compare a series collagen form, including solution, gel and sponge to investigate the topical delivery behavior of ALA. The in vivo confocal laser scanning microscopy (CLSM) study demonstrated that PpIX generation ability was different pattern after apply for 6 h. Gel type could generate high PpIX, and archived more deep of skin depth. ER -