Comprehensive study on glycoprotein detection via polymer fiber sensor decorated with dome-like Ag nanoislands and ZnO nanorods

Abstract

The surface plasmon resonance (SPR) based polymer fiber sensor is experimentally demonstrated via ZnO/Ag nano-heterostructure bi-layer coating with novel configuration. Glycoprotein detecting criteria is theoretically explained via changing the band gap and refractive index (RI) of ZnO, absorption of leaking light with analyte media, penetration depth of evanescence field, interaction of SPR with evanescence wave, hydrophilicity of ZnO surface and electrochemistry of the ZnO surface. The optical analysis of ZnO(nanorods)/Ag/polymer sample reveals that increasing the glycoprotein concentration, shifts (0.022 eV) the DL emission towards higher wavelength. Electron transferring from donor groups of glycoproteins when interact and bond with ZnO molecules are responsible for this shift. Plasmon resonance shift of ??: ~2.21º by increasing the glycoprotein dose from 0 to 0.209 ppm illustrates, interaction of SPR with evanescence wave. Sensitivity of developed polymer fiber sensor is calculated via analysis of output emission spectra and the maximum value achieved are 21 dB/ppm and 45.9 nm/ppm for intensity and wavelength respectively, having the minimum detection limit of 0.021 ppm. Our accurate designed fiber sensor can open up a new opportunity towards application in chemical and biological industries.