Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 31584
Photodegradation of Optically Trapped Polystyrene Beads at 442 nm

Authors: V. Subramanyan Namboodiri, Sajan. D. George, Steffen Hardt


Polystyrene particles of different sizes are optically trapped with a gaussian beam from a He-Cd laser operating at 442 nm. The particles are observed to exhibit luminescence after a certain trapping time followed by an escape from the optical trap. The observed luminescence is explained in terms of the photodegradation of the polystyrene backbone. It is speculated that these chemical modifications also play a role for the escape of the particles from the trap. Variations of the particle size and the laser power show that these parameters have a great influence on the observed phenomena.

Keywords: Photodegradation, Polystyrene particles, Opticaltrapping

Digital Object Identifier (DOI):

Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 1276


[1] A. Ashkin, "Forces of a single-beam gradient laser trap on a dielectric sphere in the ray optics regime", Biophys. J., vol.61, pp. 569-582, February, 1992.
[2] A. Ashkin, J. M. Dziedzic, J. E. Bjorkholm, and Steven Chu, "Observation of a single-beam gradient force optical trap for dielectric particles", Opt.Lett., vol. 11, pp. 288-290, May, 1986.
[3] A . Ashkin, "Acceleration and trapping of particles by radiation pressure", Phys. Rev. Lett, vol 24, pp. 156-159, January, 1970.
[4] A. A. R. Neves, A. Fontes, L de Y. Pozzo, A. A. de Thomaz, E. Chillce, E. Rodriguez, L. C. Barbosa and C. L. Cesar, "Electromagnetic forces for an arbitrary optical trapping of a spherical dielectric",Opt.Exp., vol. 14, pp. 13101-13106, December, 2006.
[5] K. C. Neuman and S. M. Block, "Optical trapping", Rev. of. Sci. Instru., vol 75, pp. 2787-2809, September, 2004.
[6] J. R. Moffitt,Y. R. Chemla, S. B. Smith and C. Bustamante, "Recent advances in optical tweezers", Annu. Rev. Biochem., vol. 77, pp. 205- 228, February, 2008.
[7] W. M. Lee, P. J. Reece, R. F. Marchington, N. K. Metzger and K. Dholakia, "Construction and calibration of an optical trap on a fluorescence optical microscope", Nature Protocols, vol.2, pp. 3226- 3238, December, 2007.
[8] H. Zhang and K.K. Liu, "Optical tweezers for single cells", J. R. Soc. Interface, vol.5, pp. 671-690, April, 2008.
[9] T. K. Lake, A. E. Carruthers, L. Paterson, M. Taylor, F.G. Moore, J.W. Allen, W. Sibbett and K. Dholakia, "Optical trapping and fluorescence excitation with violet diode lasers and extended cavity surface emitting lasers", Opt. Express, vol. 12, no. 4, pp 670-678, February, 2004.
[10] K. D. Crawford and K.D. Hughes, "Rapid formation and spectroscopic observation of polystyrene conjugation in individual micron diameter particles with visible radiation", J. Phy. Chem. B, vol. 101, pp 864-870, February, 1997. and references therein
[11] A Torikai, A. Takeuchi and K. Fueki, "The effect of temperature on the photodegradation of the polystyrene", Poly. Degrad. Stab. vol. 14, no. 4, pp 367-375, 1986.
[12] J. K. Simons, J. M. Chen, J. W. Taylor and R. A. Rosenberg "Fluorescence studies of the vacuum ultraviolet, synchrotron radiationinduced photochemistry of polystyrene", Macromolecules, vol.26, no.13, pp. 3262-3266, June, 1993.
[13] C.Y. Soong, W. K. Li, C. H. Liu and P. Y. Tzeng, "Theoretical analysis of photophoresis of a microscale hydrophobic particle in liquids" Opt. Express, vol.18, no.3, pp 2168-2182, February, 2010.
[14] N. Grassie and N. A Weir,"The photooxidation of polymers .II. Photolysis of polystyrene", J. Appl. Poly. Sci., vol. 9, no. 3, pp 975-986, March, 1965.
[15] K. M. Dyumayev, N. P. Kuzmina, V. V. Lobko, G. A. Matyushin, V. S. Nechitailo and A. V. Chadov, "The mechanisms of polystyrene destruction under influence of powerful UV radiation: Initial stages" Int. J. Polymeric Mater. vol. 17, pp. 121-130, August, 1992.
[16] J. W. Martin, J. W. Chin and T. Nguyen, "Reciprocity law experiments in polymeric photodegradation: a critical review" Prog. In Org. Coatings, vol.47, no 3-4, pp 292-31, September, 2003.
[17] K. Schwarzschild, "On the law of reciprocity for bromide of silver gelatin". Astrophys. J, vol.11, pp.89-91, 1900.