Capillary Blood GSH Level Monitoring, Using an Electrochemical Method Adapted for Micro Volumes

Abstract

Glutathione (γ-glutamyl-cysteinyl-glycine; also known as GSH) is an endogenous antioxidant that plays a crucial role in cell defense mechanisms against oxidative stress. It is thus not surprising that this molecule can serve as a biomarker for oxidative stress monitoring. As capillary blood is a highly accessible target for biomarking, it is a valuable bodily fluid for diagnosing human GSH levels. This study focused on the optimization of GSH measurements from micro volumes of capillary blood prior to using electrochemical detection. The optimization of experimental parameters, including the sample volume and its stability, was performed and evaluated. Moreover, we tested the optimized method as part of a short-term study. The study consisted of examining 10 subjects within 96 h of their consumption of high amounts of antioxidants, attained from a daily dose of 2 g/150 mL of green tea. The subjects’ capillary blood (5 μL) was taken at 0 h, 48 h, and 96 h for subsequent analysis. The short-term supplementation of diet with green tea showed an increase of GSH pool by approximately 38% (between 0 and 48 h) within all subjects.

Determination of glutathione in blood via capillary electrophoresis with pH‐mediated stacking

“…Researchers in a number of works have investigated fast-acting reagents of the dialdehyde series [21][22][23][24]), dansyl chloride [17], DTNB [25], NEM [26], and iodoacetyl reagents [27]. A direct method for detecting GSH and GSSG and other thiols in RBCs and capillary blood was also developed based on HPLC with an electrical conductivity detector [28,29]. Although modern HPLC is a highly sensitive (limit of quantitation [LOQ] < 1 µM) and productive method, GSH is not a very "convenient" analyte for it, especially when using reverse phase LC, which includes all the previous HPLC methods.…”

Centri‐Voltammetric GSH Detection with PDI‐C4SH as a Carrier Material

“…Because of these, various detection approaches including chromatographic [17] Raman, colorimetric [8,18–22] fluorimetric [23–25] and electrochemical techniques [26–28] have been developed and utilized for the detection of GSH. Among these techniques,…”

“…[13,14] Also it involves in wine making process resulting with low concentration in wines and helps to preserve the fruity aroma by keeping the quinones. [15,16] Because of these, various detection approaches including chromatographic [17] Raman, colorimetric [8,[18][19][20][21][22] fluorimetric [23][24][25] and electrochemical techniques [26][27][28] have been developed and utilized for the detection of GSH. Among these techniques, electrochemical methods are widely used for the determination of many molecules since they have advantages like being economical, simple, and accurate.…”