Abstract
Penicillin G (Pen-G) biosensor was developed by immobilizing penicillinase enzymes (Pen-X) onto tiny bio-chips using thioglycolic acid self-assembled monolayer (TGA-SAM). The selective pen-G biosensor was investigated by ferri/ferrocyanide couple using electrochemical method for catalytic hydrolysis of Pen-G/Pen-X in a very sensible approach. Pen-G was detected with modified bio-chip (Gold electrode of bio-chip/Thioglycolic acid/Penicillinase enzyme, in shortly AuE/TGA/Pen-X) by reliable cyclic voltammetric method at pH 7.1 in room conditions. The AuE/TGA/Pen-X modified bio-chip sensor demonstrates good linearity (50.0 nM to 5.0 mM; R=0.9987), low-detection limit (similar to 1.26 nM, SNR-3), and higher sensitivity (similar to 4.97 mu A. mu M-1. cm(-2)), lowest-small sample volume (< 70.0 mu L), good stability, selectivity, and reproducibility. To the best of our knowledge, this is the first statement in which such a very high sensitivity, low-detection limit, and low-sample volume are required for Pen-G biosensor using AuE/TGA/Pen-X bio-chips assembly. The results of these studies have introduced for biomedical applications with interesting assembly (AuE/TGA/Pen-X) towards the development of selective Pen-G biosensors. The AuE/TGA-SAM system was implemented a facile approach to the integration of Pen-X/Pen-G fabricated bio-chips, which can offer analytical access to a large group of enzymes for wide range of biomedical applications in health-care fields.