The Construction of Biological Computing Platform Based on Multiple-Stimuli Responsive Bienzyme Electrocatalysis

Abstract

Biomolecular logic gate systems and parity checker based on stimuli-responsive film electrode were developed. {CS/Con A}n-PDEA-GOD-HRP films were constructed on pyrolytic graphite (PG) electrode surface by specific recognition, layer by layer assembly of CS (Chitosan) and Con A (Concanavalin A) and chemical polymerization of PDEA-GOD-HRP (PDEA = poly (N,N-diethyl acrylamide), GOD = glucose oxidase, HRP = horseradish peroxidase). The electroactive probe, potassium ferricyanide (K3Fe(CN)6), exhibited cyclic voltammograms (CV) switching behaviors to pH, temperature and methanol on film electrodes. This switching property of the {CS/Con A}n-PDEA-GOD-HRP films could be further used to realize multiple responsive catalytic oxidation of glucose sequentially by HRP and GOD entrapped in the films with K3Fe(CN)6 as the electron transfer mediator. The addition of glucose could amplify CV peak current through bioelectrocatalysis. Based on experimental results, a 4–input/5–output binary logic gate system with glucose, pH, temperature and methanol as input and peak current (Ipc) as output was constructed, a ternary INHIBIT logic gate, a ternary AND logic gate and a parity checker were established. It opens up the possibility of building other complex molecular logic devices based on bienzyme bioelectrocatalysis.