Products

Fluorometric & Colorimetric GST Assay Kits

Glutathione (GSH) is the major intracellular low-molecular-weight thiol and plays a critical role in cellular defense against oxidative stress in tissues and cells. Glutathione S-transferase (GST) is an essential enzyme involved in detoxification of xenobiotics mediating conjugation of glutathione with those compounds.

The Fluorometric and Colorimetric GST Assays can detect GST activity in crude cell lysate or purified protein fractions and the kits also suited for quantitation of GST-tagged fusion proteins. They are based upon the GST-catalyzed reaction between GSH and the GST substrate CDNB (Colorimetric Kit) or MCB (Fluorometric Kit).

CDNB has the broadest range of isozyme detectability (e.g. α-, µ-, phi-, and other GST isoforms). Under certain conditions, the interaction between glutathione and CDNB is totally dependent on the presence of active GST. Detection limit is approximately 10 ng active GST/assay.

The free form of MCB is almost non-fluorescent, whereas the dye fluoresces blue (Ex/Em = 380/461 nm) when reacting with glutathione. GST catalyzes the MCB-glutathione reaction, and the fluorescence levels are proportional to the amount of GST present in the reaction. Therefore, the GST level in samples can be easily detected using a fluorometer or a 96-well fluorometric plate reader.

Fluorometric Glutathione Detection Kit

Diminished glutathione (GSH) levels occur at the early stages of apoptosis. The PromoKine Fluorometric Glutathione Detection Kit provides a simple in vitro assay for detecting the GSH changes in apoptosis and other pathological processes. The assay utilizes a dye (monochlorobimane, MCB) that has a high affinity for glutathione. The unbound dye is almost nonfluorescent; whereas the dye fluoresces blue (excitation = 380 nm; emission = 461 nm) when bound to reduced or oxidized glutathione. The reaction is catalyzed by glutathione S-transferase (GST). Thus, the decrease in glutathione level in apoptotic cells can be easily detected using a fluorometer or a 96-well fluorometric plate reader.

Colorimetric Glutathione Detection Kit

The Colorimetric Glutathione Detection Kit provides a convenient, colorimetric method for analyzing either total glutathione or only the reduced form of glutathione using a microtiter plate reader. The assay utilizes the glutathione recycling system with DTNB and glutathione reductase: GSH is regenerated from GSSG by glutathione reductase, and will again react with DTNB to produce yellow 2-nitro-5-thiobenzoic acid that can be determined spectrophotometrically at 412 nm. This recycling reaction dramatically improves the sensitivity of total glutathione detection - the kit can quantify total glutathione from 1-100 ng/well. For detecting lower glutathione concentrations, such as in blood samples, increasing reaction time will significantly improve the signal. The kit can also specifically detect the reduced form of glutathione (GSH) by omitting the glutathione reductase from the reaction mixture.

Colorimetric Glutathione Reductase Activity Kit

PromoKine’s Colorimetric Glutathione Reductase Activity Kit has been designed for measuring glutathione reductase (GR) activity in biological samples. It is highly sensitive and well suited for high-throughput. The assay is based on the GR-catalysed reduction of GSSG to GSH, which reacts with 5,5′-Dithiobis(2-nitrobenzoic acid) (DTNB) to generate the yellow TNB2-. The kit can detect 0.1 – 40 mU/ml GR in various samples.

References, Questions & Answers

Product Name Description Size Catalog Number Information Prices
Colorimetric GST Assay Kit Detecting GST activity by spectrophotometer at 340 nm 100 assays PK-CA577-K263 click to select country
Fluorometric GST Assay Kit Detecting GST activity by fluorometer or fluorescence plate reader. 100 assays PK-CA577-K260 click to select country
Colorimetric Glutathione Detection Kit Colorimetric Glutathione Detection Kit for detecting the GSH changes in apoptosis and other pathological processes 100 assays PK-CA577-K261 click to select country
Fluorometric Glutathione Detection Kit Glutathione Detection Kit for apoptosis and other pathological processes 100 assays PK-CA577-K251 click to select country
Colorimetric Glutathione Reductase Activity Kit Colorimetric quantitation of glutathione reductase activity 200 assays PK-CA577-K761 click to select country
GST Inhibitor-2 (ethacrynic acid) An effective inhibitor of Glutathione S-transferase (GST) 1 mg PK-CA577-1556-1 click to select country
GST protein (active) Active Glutathione S-transferase 1 mg PK-RP577-1243-1 click to select country
Oxidized Glutathione (GSSG) Hydrogen acceptor in the enzymatic determination of NADP and NADPH 1 g PK-CA577-1241-1 click to select country
Reduced Glutathione (GSH) A biological antioxidant that helps protect cells from reactive oxygen species 1 g PK-CA577-1242-1 click to select country