Protein film voltammetry: electrochemical enzymatic spectroscopy. A review on recent progress

Abstract

This review is focused on the basic principles, the main applications, and the theoretical models developed for various redox mechanisms in protein film voltammetry, with a special emphasis to square-wave voltammetry as a working technique. Special attention is paid to the thermodynamic and kinetic parameters of relevant enzymes studied in the last decade at various modified electrodes, and their use as a platform for the detection of reactive oxygen species is also discussed. A set of recurrent formulas for simulations of different redox mechanisms of lipophilic enzymes is supplied together with representative simulated voltammograms that illustrate the most relevant voltammetric features of proteins studied under conditions of square-wave voltammetry.

Measuring the Electrode Kinetics of Surface Confined Electrode Reactions at a Constant Scan Rate

“…A plethora of intriguing studies has been conducted in relation to the kinetics of charge transfer processes at liquid/liquid interfaces [18][19][20][21][22][23], electrochemistry of immobilized proteins [24,25], and catalytic mechanisms [26][27][28], revealing that SWV is highly suited for both mechanistic and kinetic characterization of electrode reactions, besides its excellent analytical performances [29][30][31][32][33][34] and its appropriateness for bioanalytical applications [35][36][37][38][39][40][41].…”

Square‐Wave Voltammetry: A Review on the Recent Progress

“…In the recent years, the SW voltammetry has emerged as a viable and cheap alternative to the expensive and time-consuming techniques (such as chromatography, or spectrophotometry, for example) for the determination of inorganic and biologically important compounds. The simple working set-up, the quick time of performing the measurements, the different modes that can be applied, together with its sensitivity, make the SWV a technique of choice for quantification of important classes of compounds such as proteins [82], vitamins [83], phenols [84][85][86][87][88], benzoquinones [89], pesticides, herbicides and fungicides [90][91][92][93][94][95][96][97][98], alkaloids [99], terpenoids [100], heavy metals [101][102][103][104][105][106][107][108][109][110][111][112][113][114][115][116], and drugs [117,118]. One of the most valuable ability of SWV is its application for simultaneous determination of compounds with similar structures present in various pharmaceutical and physiological samples.…”

New aspects of the electrochemical-catalytic (EC’) mechanism in square-wave voltammetry

“…A lot of theoretical features of the EC (electrochemicalchemical), CE (chemical-electrochemical), ECE (electrochemicalchemical-electrochemical), EC' (electrochemical-catalytic) systems under voltammetric conditions at various electrodes are appropriately elaborated in several excellent books [1][2][3][4][5][6], theoretical studies and reviews [7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. The so-called electrocatalytic regenerative mechanism (often referred to as EC' or ECat mechanism) is one of the most intriguing from a theoretical point of view, since it differs in many aspects from the other three mechanisms (EC, CE, and ECE) [1,[5][6][7][8]11,13,16,[18][19][20][21][22][23][24][25][26]. The EC' electrode mechanism comprises regeneration of the initial electroactive species involved in the electrode reaction via homogeneous redox reaction of the electrochemically generated product with other redox species present in the electrolyte solution.…”