Abstract
Two ruthenium complexes [Ru(phendione) 3] 2+ and [Ru(tpy) (bpy)H 2O] 2+ were tested as redox mediators for the electrocatalytic enzyme-coupled oxidation of malate and lactate with their respective dehydrogenase enzymes. Both complexes were capable of regenerating NAD + after its enzymatic reduction, but with varying current density as shown by cyclic voltammetry. Studies were performed at different concentrations of NAD + and the mediator and with different number of enzyme units. The best experimental conditions were used in experiments with different substrate concentrations. The results were fitted to the Michaelis-Menten equation giving the following K M and V max values in carbonate buffer at pH 9.3. Lactate dehydrogenase ( r = 0.9999): K M = 9.784 ± 1.163 mM; k cat = 3.819 ± 0.104 s −1. Malate dehydrogenase ( r = 0.9999): K M = 3.934 ± 0.722 mM; k cat = 3.376 ± 0.171 s −1.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
