Editors’ Choice—Review—From Polarography to Electrochemical Biosensors: The 100-Year Quest for Selectivity and Sensitivity

Abstract

This is a story of the 100-year path for voltammetric electroanalytical chemistry from the serendipitous discovery of polarography by Jaroslav Heyrovsky in 1922 to the miniature biosensors of today. In spite of issues with the dropping mercury electrode (DME), polarography was dominant for almost 50 years due to the good quantitative results it produced. Then, significant developments led to today’s methods with drastic improvements in detectable concentration and amount, selectivity, ease of use, and breadth of application. Important steps forward include the shift from the DME to solid electrodes, the strategic modification of electrode surfaces chemically and with membranes, electrochemistry in thin layers of solution with the associated decrease in sample amount from milliliters to microliters and below, liquid chromatography with electrochemical detection, more powerful and smaller instrumentation, microfabrication of electrodes, pulse techniques that improved concentration limits of detection by discriminating against double layer charging, spectroelectrochemistry for enhanced selectivity by electrochemically changing a spectroscopic signal, cyclic voltammetry for the general utility that makes it the work-horse of voltammetry, and biosensors that dramatically expanded the applicability of voltammetry through the use of nature’s biological catalysts (enzymes) and capture agents (antibodies, aptamers).

Future of Voltammetry

“…One of the most important applications of voltammetry is in the design of specific biosensors. 5,[91][92][93] Voltammetric biosensors are devices that take advantage of the sensitivity of a particular electroanalytical method and the inherent selectivity of the defined biological system. In most voltammetric biosensors, a defined biological substance, commonly attached to the surface of the working electrode, has the ability to recognize its specific counterpart (the analyte) present in the voltammetric cell.…”

“…In last 25 years, a huge impact of voltammetry on the field of biosensor design has been witnessed. [91][92][93][94] Because many recent reviews report on a large number of voltammetric sensors, we refer the readers to some of those excellent works. [91][92][93][94][95][96] At this point, it is worth mentioning one remarkable achievement of voltammetry in probing the chemical features of so-called redox proteins and enzymes.…”

“…[91][92][93][94] Because many recent reviews report on a large number of voltammetric sensors, we refer the readers to some of those excellent works. [91][92][93][94][95][96] At this point, it is worth mentioning one remarkable achievement of voltammetry in probing the chemical features of so-called redox proteins and enzymes. 97 The technique, named "protein-film voltammetry" (PFV), introduced by Armstrong et al [98][99][100][101] is seen as a cornerstone of voltammetric methodologies de-signed to obtain insight into the chemistry of water-insoluble redox enzymes that keep their activity even after being immobilized on the surface of a working electrode.…”

Design‐of‐Experiments‐Based Optimisation of Vanillin Yield from Kraft Lignin Using Pulse Electrolysis and Thermolysis

“…[21][22][23] This may also lead to an increased sensitivity, [24,25] diminished surface poisoning, [23] or even the modulation of the selectivity. [22,26] However, it is important to note that when an experiment uses different pulse sequences, each of the additional variables can have an impact on all previous ones, quickly generating complicated and difficult-to-predict behaviours. [27,28] Applied statistics in experimental designs can be utilised to gain increased knowledge of such complicated parameter networks and interactions, [29,30] including multivariate designs capable of simultaneously determining effects that standard univariate designs cannot detect.…”

Development of Electroanalytical Methods Using Different Electrodes for the Determination of Progesterone (P4) in Pharmaceutical Formulations and Human, Cow and Goat Milk

“…Electroanalytical methods with different electrodes are useful alternatives with important advantages, including low-cost instrumentation and materials, good sensitivity and selectivity, as well as portability, if necessary. Hanging mercury drop electrode (HMDE) form nearly ideal electrode that have been used for many decades, especially for cathodic processes and mainly due to good adsorptive properties [20][21][22][23]. The determination of P4 with mercury electrodes is based on reduction of the 3-keto group in ring A [24].…”