Change in the surface density of immobilized enzyme molecules induced by photoelectron processes in a silicon substrate

Scanning Probe Microscopy 2018

Kozlowski, A.V.^1 ; Kiseleva, E.D.^1 ; Maslennikova, A.A.^1 ; Stetsyura, S.V.^1

Department of Nano- and Biomedical Technologies, Saratov State University, Saratov

410012, Russia^1

关键词: Adsorbed enzyme;    Controllable parameters;    Immobilized enzyme;    Nonmonotonic changes;    Polyethyleneimine;    Salt concentration;    Silicon substrates;    Surface density;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/443/1/012016/pdf
DOI  :  10.1088/1757-899X/443/1/012016

来源: IOP

【 摘 要 】

We report on a change in the number of adsorbed glucose oxidase molecules depending on both salt concentration and illumination of a silicon substrate during glucose oxidase adsorption on its surface. Glucose oxidase molecules were adsorbed from its aqueous solution onto a silicon substrate either with a polyethyleneimine layer or without it. Based on obtained atomic force microscopy (AFM) data, it was found that addition of salt led to a more prominent effect of photo-assisted adsorption. In addition, illumination led to a monotonic change in adsorbed enzyme coverage (either decrease or increase depending on silicon substrate conductivity type), while variation of salt concentration resulted in the nonmonotonic change. The obtained results can be used for fabrication of biosensors with easily controllable parameters such as sensitivity, lower limit of analytic detection, etc.