Enhanced Radiative Decay Rate of Confined Green Fluorescent Protein in Polyvinylpyrrolidone-Based Nanofiber

Abstract

Green fluorescent protein (GFP) molecules are encapsulated by polyvinylpyrrolidone material in the form of nanofibers to study their diameter dependence of the fluorescence decay rate. Fluorescence dynamics of the confined GFP is governed by the Purcell effect. It is demonstrated that the electrospun nanofibers are quite controllable geometries and are suitable local photonic environments for exploring such effects. The chromophore of GFP, responsible for the intense green fluorescence, is attached to the α helix and perfectly surrounded by an 11-stranded β-barrel cylinder. It is clearly observed that the molecular structures of the confined GFP protein molecules are well protected and are able to maintain their fluorescence properties.

Purcell radiative rate enhancement of label-free proteins with ultraviolet aluminum plasmonics

“…Each system contains typically several tens of tryptophan emitters which are closely packed at a nanometer distance surrounded by other amino acids acting as fluorescence quenchers via electron or proton transfer [17,18]. The modifications of emission rates for specific proteins have been revealed in the optical range, including the pigment protein complex LH2 [19,20] and the green-fluorescent protein GFP [21]. However, these cases refer to specific pigment protein families featuring high absorption and emission in the visible, it cannot account for the collective UV emission of tryptophan and tyrosine amino acids present in the majority of proteins.…”