Cyclic voltammetry and electrochemical impedance simulations of the mediator-type enzyme electrode reaction using finite element method

Analytical expression for the model that describes the heterogeneous reaction-diffusion process with immobilized enzyme (penicillin G acylase)

This research article examines the reaction-diffusion process in an immobilized enzyme batch reactor. The model incorporates strongly non-linear factors that are associated with standard Michaelis-Menten kinetics. The non-linear reaction-diffusion equations for substrate and product concentrations have been approximated analytically. Employing two different semi-analytical methods, Akbari-Ganji's method (AGM) and the modified Adomian decomposition method (MADM), to compute the dimensionless steady-state solutions to the system of non-linear differential equations for all values of reaction parameters. In addition, the dynamics of the mean integrated effectiveness factor of penicillin acylase in porous spherical particles have been presented for the determination of the local effectiveness factor. In order to gauge the potency of our proposed solution, we compare two semi-analytical results with a numerical result that are in good agreement across the whole concentration range. The proposed formulation aims to simulate the dynamic performance of the system utilizing the parameters and would enhance the determination of the optimum particle size for enzyme catalysts.

Bioelectrocatalysis for CO2 reduction: recent advances and challenges to develop a sustainable system for CO2 utilization

Activation and turning CO₂ into value added products is a promising orientation to address environmental issues caused by CO₂ emission. Currently, electrocatalysis has a potent well-established role for CO₂ reduction with fast electron transfer rate; but it is challenged by the poor selectivity and low faradic efficiency. On the other side, biocatalysis, including enzymes and microbes, has been also employed for CO₂ conversion to target C_n products with remarkably high selectivity; however, low solubility of CO₂ in the liquid reaction phase seriously affects the catalytic efficiency. Therefore, a new synergistic role in bioelectrocatalysis for CO₂ reduction is emerging thanks to its outstanding selectivity, high faradic efficiency, and desirable valuable C_n products under mild condition that are surveyed in this review. Herein, we comprehensively discuss the results already obtained for the integration craft of enzymatic-electrocatalysis and microbial-electrocatalysis technologies. In addition, the intrinsic nature of the combination is highly dependent on the electron transfer. Thus, both direct electron transfer and mediated electron transfer routes are modeled and concluded. We also explore the biocompatibility and synergistic effects of electrode materials, which emerge in combination with tuned enzymes and microbes to improve catalytic performance. The system by integrating solar energy driven photo-electrochemical technics with bio-catalysis is further discussed. We finally highlight the significant findings and perspectives that have provided strong foundations for the remarkable development of green and sustainable bioelectrocatalysis for CO₂ reduction, and that offer a blueprint for C_n valuable products originate from CO₂ under efficient and mild conditions.