Biosensor for Aluminum(III) Based on ÃÂ±-Chymotrypsin Inhibition using a Disposable Screen-Printed Carbon Electrode and Acetyl-Tyrosine Ethyl Ester as Substrate
- *Corresponding Author:
- Miriam Barquero-Quirós
University of Costa Rica
CELEQ, San Pedro de Montes de Oca
11500-2060 San José, Costa Rica
E-mail: [email protected]
Received date: March 25, 2015; Accepted date: April 15, 2015; Published date: April 20, 2015
Citation: Barquero M, Dominguez O, Alonso MA, Arcos MJ (2015) Biosensor for Aluminum(III) Based on a-Chymotrypsin Inhibition using a Disposable Screen-Printed Carbon Electrode and Acetyl-Tyrosine Ethyl Ester as Substrate. Chem Sci J 6:089. doi: 10.4172/2150-3494.100089
Copyright: © 2015 Quirós MB, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
We report on a new amperometric assay for Al(III) ions based on the inhibition of α-chymotrypsin enzyme. The immobilization of the enzyme was performed on screen-printed carbon electrodes modified with gold nanoparticles and polyvinyl alcohol. N-acetyl-tyrosine ethyl ester, used as enzyme substrate, produces an oxidation amperometric signal, which at increasing aluminum concentration is diminished. The developed system has a detection limit of 1.5 ± 0.1 μM (n=7) for Al(III). The reproducibility of the method is 6.6% (n=5) and its repeatability is 8.2% (n=3). Main interferences at low concentration, include As(V), Cd(II), and Mo(VI) ions. The developed method was successfully applied to the determination of Al(III) in spiked white wine sample. Results agree with the certified value giving a value of percent recovery of 103 ± 4% (n=4).