An Electrochemical Microfluidic Platform for Human P450 Drug Metabolism Profiling

Abstract

This paper is the first report of a P450-electrode in a microfluidic format. A 30 μL microfluidic cell was made in poly(methyl methacrylate) containing the inlet, outlet, and reaction chamber with two electrode strips, one of which contains the human cytochrome P450 3A4 covalently bound to gold via a 6-hexanethiol and 7-mercaptoheptanoic acid (1:1) self-assembled monolayer. The electrochemical response of the P450-electrode in the microfluidic cell was tested using four drugs that are known substrates of P450 3A4: quinidine, nifedipine, alosetron and ondansetron. Titration experiments allowed the electrochemical measurements of K(M) for the four drugs, with values of 2.9, 29.1, 113.4, and 114.1 mM, respectively. The K(M) values are found to be in good agreement and correctly ranked with respect to the published literature on human liver microsomes and baculosomes: [ondansetron ≈ alosetron > nifedipine > quinidine]. The results presented in this paper represent a step forward for a rapid evaluation of the interaction of P450 and drug, requiring small volumes of new chemical entities to be tested.

Electrochemical Detection of Human Cytochrome P450 2A6 Inhibition: A Step toward Reducing Dependence on Smoking

“…[15][16][17][18][19][20][21][22][23][24] Particular interest has been focused on the improvement of the electronic coupling of the enzyme with the electrode surface and of its catalytic efficiency. In a fully coupled system reducing equivalents and molecular oxygen consumed are stoichiometrically equivalent to the product formed.…”

Microfluidic Electrochemical Array for Detection of Reactive Metabolites Formed by Cytochrome P450 Enzymes

“…33–36 A microfluidic device featuring immobilized cyt P450 fusion proteins on gold electrodes for drug metabolite profiling was reported recently. 37 …”

Prospects on the Hyphenated Electrochemistry and Mass Spectrometry as a Practical Analytical Technique in the Assessment of Oxidative Drug Metabolism

“…This is due to the fact that the enzyme immobilization should not inactivate or change the enzyme behavior. The possibility of using electrodes modified with enzymes in micro fluidic can add value to their industrial applications [32]. Different strategies using enzymes in mimicry of oxidative drug metabolism are already discussed in an earlier review article [9].…”