Electrochemical Determination of Thiols: A Perspective

Abstract

Monitoring thiol concentrations within physiological fluids has risen to considerable importance within the biomedical communities as our appreciation of the various roles that these compounds can perform has increased. Their utilization as biomarkers for numerous clinical conditions has prompted considerable interest in the development of analytical protocols that enable speedy measurements to be made. As such, a large number of procedures have arisen. This perspective highlights the contexts where physiological thiol measurements are required and describes the basis of many of the current electrochemical approaches to their determination. The collation of information from a broad range of sources covering the major electrochemical approaches (direct, indirect, and post column/capillary detection) has been achieved and the salient points of each technique critically appraised. The various characteristics and limitations of the systems are compared and contrasted with the analytical parameters (matrix, methodology, detection limit etc) from each major grouping tabulated to aid direct comparison.

Immunosensing platform based on gallium nanoparticle arrays on silicon substrates

“…Standard kits usually rely on spectrofluorimetry (Meyer et al 2001;Xu et al 2015) and ELISA (antigen-antibody recognition) and reach limits of detection around 0.1-0.5 µg/mL (0.325-1.625 µM). Other techniques such as electrochemistry (Harfield et al 2012;Ndamanisha et al 2009;White et al 2002), high-performance liquid chromatography (Lu et al 2007;Vacek et al 2006;Zhang et al 2005), gas chromatography (Kataoka et al 1995), or quartz crystal microbalance (Gerdon et al 2005) have been employed enabling the detection at lower levels. However, all these methods have advantages but also drawbacks, such as less selectivity against other aminoacids or the time consuming characteristics, that make the analysis tedious and complicated.…”

Selective Thiol Detection in Authentic Biological Samples with the Use of Screen-printed Electrodes

“…[1][2][3][4][5][6][7][8][9][10][11] Thiols, such as homocysteine (HCy) and glutathione (GSH), are ubiquitous in physiological fluids as they play an important role in maintenance, antioxidation protection and metabolism. 9,[12][13] Levels of these thiols have been reported to be important as changes at the cellular role may have implications to conditions such as arteriosclerosis, 5,12,14 leukaemia, [14][15] cancer, 14,16 Alzheimer's, 5,[17][18][19] and/or Parkinson's disease. 5,[17][18] As such, selective detection is valuable for the biomedical community as it may provide a versatile diagnostic pathway to monitor various conditions.…”

Electrocatalytic oxidation of glutathione at carbon paste electrode modified with 2,7-bis (ferrocenyl ethyl) fluoren-9-one: application as a voltammetric sensor

“…A series of modified electrodes have been used based on enzymes [21,22], organometallic compounds [23,24], organic compounds [25], tetrathiafulvalene-tetracyanoquinodimethane (TTF-TCNQ) complex [26], etc. [27]. Recently, electrochemical determination of thiols was reviewed by Compton and coworkers [28].…”