Bacteriorhodopsin Film And Its Molecular Optical Anisotropy Characteristic Research

Bacteriorhodopsin or BR is a kind of polymeric biomaterial with obviously photochromic characteristic。 Because of its remarkable photochromic properties and optical features, more and more widely applied in the field of optical information storage.This paper conducted a BR-D96N photoinduced anisotropy of the research work, which is a genetically modified bacteriorhodopsin.In the experimental research, with single photon absorption photo-induced optical anisotropy of BR-D96N films (in short SPA-POA). First of all, dichroism and birefringence of the BR film B-type is measured; and according to the analysis to obtain optimum excitation condition which is3.0mW/cm2, DCF∞_max≈0.01363, BRF∞_max≈0.00537; Then, dichroism and birefringence of the BR film X-type is measured, and analysis of optimum excitation conditions which is/I650=30.0mW/cm2, I405=60.0mW/cm2,getting the DCF∞_max≈0.15849and BRF∞_max-0.03741and the best ratio of photoinduced anisotropy is2.0. Finally, with B-type SPA-POA comparing and analyzing the data of POA increase multiples is11.6. In theory fit the experimental data, in the first place, according to the theoretical derivation which get the relationship between macro photoinduced anisotropy and molecular optical anisotropy of BR film, and the result show that,the Γ smaller,the anisotropy stronger of BR molecule; Afterwards, fitting the B-type and X-type SPA-POA experimental measurement data of BR film; At last, getting the B and M states of the BR molecule single photon absorption optical anisotropy best-fit values which is Δn0=3.2E-3*0.2、ΓB�'M=0.1、ΓM�'B=0.01. In the theoretical simulation,the Γ of X-type SPA-POA is smaller which explains the experimental X-type SPA-POA photoinduced anisotropy reasons for the increase.