Abstract

Exogenous fluorescent agents such as green fluorescent protein (GFP) have been widely used as biological indicators in bioimaging techniques. Although GFP and its mutants have been used in many applications, their optical properties have not been completely investigated, especially when they are under various environmental conditions. In this research, we developed a spectrum-analyzing system to investigate the fluorescent properties of GFP in the environments of different temperatures. We found that the fluorescent spectrum of GFP consisted of two components that might come from the transitions between different electronic energy states where the quantum efficiencies of the two components varied with different temperature. This effect was expected to come from the thermal effect on the electron populations in the molecular energy states of GFP. Furthermore, GFP was used as fluorescent marker to monitor the infection process of cells by virases with a dynamic spectral imaging system. The recombinant baculovirases containing the red and green fluorescent protein gene that can simultaneously produce dual fluorescence were used as vectors in insect cells. The system was used to monitor the spatial distribution of fluorescent spectra of cells infected by virus during the process of infection.

© 2007 SPIE