High enzymatic activity preservation of malate dehydrogenase immobilized in a Langmuir-Blodgett film and its electrochemical biosensor application for malic acid detection
By Gur, Bahri; Isk, Mesut; Kransan, Kader Dagc; Alanyaloglu, Murat; Beydemir, Sukru; Meral, Kadem
Published in RSC Adv
The Royal Society of Chemistry
2016
Abstract
In this study, malate dehydrogenase (MDH) enzyme was immobilized on a cation octadecylamine (ODA+) monolayer at the air-water interface. Pressure-area ([small pi]-A) isotherm studies confirmed that the ODA-MDH system formed a stable monolayer at the air-water interface. The as-prepared MDH-ODA monolayer was transferred onto an indium tin oxide coated glass substrate (ITO) by the Langmuir-Blodgett (LB) method as an MDH-ODA/ITO LB film and characterized using FT-IR, SEM and UV-Vis absorption spectroscopy. The catalytic activity of the enzyme immobilized electrode (MDH-ODA/ITO) was assayed by sensing malic acid (MA) in the range of 10.0-50.0 mM. The high and preserved enzymatic activity of MDH in in vitro media was explored by following the absorbance (A340 nm) of nicotinamide adenine dinucleotide (NADH). Moreover, the highly sensitive electrochemical biosensor behavior of the MDA-ODA/ITO electrode for MA detection was displayed by cyclic voltammetry studies. The electrochemical studies revealed that a voltammetric current from the MDA-ODA/ITO electrode was obtained, while the ODA/ITO electrode did not show this current response. The MDA-ODA/ITO ?demonstrated sensitive electrochemical sensor ability for quantification of MA in both standard solutions and real samples.
Microsoft is Ending Support for Windows 7
Microsoft will discontinue support for Windows 7 on January 14, 2020 which means Gamry will also be discontinuing support for Windows 7. If you are upgrading to Windows 10, like many companies and institutions, you need to be running Version 7 of our s oftware . Please note that only USB and Ethernet-based instruments can run in Version 7. Eligible users can download the latest version of our software through our online Client Portal .
If you haven't already registered your instrument, you can do so through the Client Portal .
Please email Technical Support if you have any questions regarding this transition. Please be sure to include your instrument model and serial number when contacting us.