Chemically enhanced D96N-mutant bacteriorhodopsin film as an advanced optical material

摘要

The combination of the genetic engineering and chemical additive has been used in an attempt to obtain much longer M-state lifetime of bacteriorhodopsin-PVA film. Different compositions of D96N-mutant bacteriorhodopsin-PVA film with the diaza-15-crown-5 (l,4,10-trioxa-7,13-diazacyclopentadecane) additive were prepared and their spectral and kinetic transformation were investigated by absorbance spectroscopy. As the molecular ratio of BR_(D96N)/diaza-15-crown-5 ranging from 1:50-1:150, the decay of the M-state was slowed down gradually. The fitting of the M-state decay kinetics curves needs a three-exponential-function to get sufficiently small residuals. At the highest additive concentration, the photochromism time of BR_(D96N) film could last as long as one and a half hours. This provides a benefit to the BR_(D96N) as a candidate material for optical applications under ambient conditions.