Glutathione (GSH GSSG) Assay Kit

NWLSS | Northwest Life Science Specialties, LLC.
Glutathione (GSH GSSG) Assay Kit
NWK-GSH01 $395.00 each

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(Toll-Free US/Canada)


A kinetic, rate based assay for quantification of total glutathione (GSH), both reduced and oxidized, in a variety of samples including blood, plasma, tissues and cultured cells. This kit is also suitable for measurement of oxidized GSH (GSSG) after scavenging of reduced GSH.

Advantages of the NWLSS™ Glutathione (GSH GSSG) Assay:
  • Excellent sensitivity as low as 5 pMol
  • Can detect glutathione disulfide (GSSG) when samples are pre-treated with suitable thiol-scavenger, such as 4vinylpyridine (4VP) or NEM


Glutathione (GSH, g-glutamylcysteinylglycine), the primary non-protein sulfhydryl in aerobic organisms is synthesized in most cells. The ubiquitous tripeptide is formed by the combination of glutamic acid and cysteine, catalyzed by g-glutamylcysteinyl synthetase. Glycine is then added by glutathione synthetase to form GSH.

In addition to donating an electron during the reduction of hydroperoxides to the respective alcohols (or water in the case of hydrogen peroxide), GSH functions as a co-substrate in the metabolism of xenobiotics catalyzed by glutathione S-transferases. It is also a co-factor for several metabolic enzymes is involved in intracellular transport, functions as an antioxidant and radioprotectant and facilitates protein folding and degradation.

Test Principle

The NWLSS™ Glutathione Assay is a modification of the method first described by Tietze. The general thiol reagent, 5-5'-dithiobis[2-nitrobenzoic acid] (DTNB, Ellman's Reagent) reacts with GSH to form the 412 nm chromophore, 5-thionitrobenzoic acid (TNB) and GS-TNB. The GS-TNB is subsequently reduced by glutathione reductase and β-nicotinamide adenine dinucleotide phosphate (NADPH), releasing a second TMB molecule and recycling the GSH; thus amplifying the response. Any GSSG initially present in the reaction mixture or formed from the mixed disulfide reaction of GSH with GS-TNB is rapidly reduced to GSH and detectable in the assay.

When trying to measure a 4-VP treated sample for GSSG we added 50 uL DTNB to 50 uL Sample and the wells turned yellow before adding any GR to the wells. Are we doing something wrong?

Regarding the early yellow color development: It's likely that the samples are too basic. This can be due to an error in neutralization of the MPA by NaOH.

Can the NWK-GSH01 kit be adapted for use on an autoanalyzer?

We have not yet adapted our current assay for modern automated instruments but yes it is possible to adapt Tietze based GSH methodologies for use on automated instruments.

Are red blood cells (erythrocytes) and white blood cells (lymphocytes) fully disrupted during deproteination using cold 5% metaphosphoric acid (MPA)?

RBC’s should be fully disrupted after treatment with 5% MPA however, in the case of whole blood, some white cells may survive intact. Since the concentration of RBC GSH is so much higher than that of WBC’s it is unlikely that GSH lost to surviving WBC’s would change the data much for whole blood GSH. If it is concern we recommend low level sonication to make sure all white cells are properly disrupted.

Are there any other acid reagents that can be used in place of MPA for sample deproteination?

Yes, Trichloroacetic Acid (TCA) can also be used.

According to the product insert whole blood sample can be tested using product NWK-GSH01. But on Page 7 of the product insert it says: “Collect samples using EDTA, heparin, citrate or ACD anticoagulant." We are confused about this. Does "Whole blood" just mean "Plasma"?

No whole blood does not mean plasma but whole blood does need to be collected with anticoagulant present. If anticoagulant is not present the sample will clot and cease to be representative of whole blood (a non-clotted mixture of plasma, RBCs and white cells). Whole blood that is left to clot will yield serum and a big clot that is not acceptable for testing GSH.
Methionine and Choline Supply during the Periparturient Period Alter Plasma Amino Acid and One-Carbon Metabolism Profiles to Various Extents: Potential Role in Hepatic Metabolism and Antioxidant Status
Zheng Zhou, Mario Vailati-Riboni, Daniel N. Luchini and Juan J. Loor
Nutrients ,  2017, 9(1), 10

View Abstract

Mechanisms of Fatal Cardiotoxicity following High-Dose Cyclophosphamide Therapy and a Method for Its Prevention
Takuro Nishikawa, Emiko Miyahara, Koichiro Kurauchi, Erika Watanabe, Kazuro Ikawa, Kousuke Asaba, Takayuki Tanabe, Yasuhiro Okamoto, Yoshifumi Kawano
Plos One ,  June 26, 2015

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Rumen-protected methionine compared with rumen-protected choline improves immunometabolic status in dairy cows during the peripartal period
Z. Zhou, O. Bulgari, M. Vailati-Riboni, E. Trevisi, M.A. Ballou, F.C. Cardoso, D.N. Luchini, J.J. Loor
Journal of Dairy Science, August 31, 2016, Available Online

View Abstract

Decrease in acrolein toxicity based on the decline of polyamine oxidases
Takeshi Uemura, Mizuho Nakamura, Akihiko Sakamoto, Takehiro Suzuki, Naoshi Dohmae, Yusuke Terui, Hideyuki Tomitori, Robert A. Casero Jr, Keiko Kashiwagi, Kazuei Igarashi,
The International Journal of Biochemistry & Cell Biology, Volume 79, October 2016, Pages 151–157

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Progression of Ventricular Remodeling and Arrhythmia in the Primary Hyperoxidative State of Glutathione-Depleted Rats
Sayaka Kurokawa, Shinichi Niwano, Hiroe Niwano, Shoko Ishikawa, Jun Kishihara, Yuya Aoyama, Tomoko Kosukegawa, Yoshihiko Masaki, Tohru Izumi
Circulation Journal , (2011) Vol. 75, No. 6 p. 1386-1393

View Abstract

Browse all Citations

For Research Use Only

Catalog Number: NWK-GSH01
Format: 192 tests presented as 2 X 96 well microtiter plate assays. Cuvette format for spectrophotometers also available.
Sample Requirements: Whole blood, plasma, tissues and cell lysates.
Specificity: Total Glutathione (GSH plus GSSG)
Sensitivity: 0.1 µM using standard method (for whole blood & some tissue types). 0.005 µM using modified high sensitivity method (for samples with lower GSH levels such as plasma or for detection of GSSG after reduced GSH has been scavenged). Contact NWLSS for details.
Intended Use: Quantitative measurement of total GSH (reduced plus oxidized form)
Storage and Stability: 12 months from date of manufacture if stored at 2-8C
Kit Contents: DTNB Reagent
NADPH Diluent
GR Enzyme
GSH (GSSG) Calibrator
Assay Buffer
Random Citation

Excess Dietary L-Cysteine Causes Lethal Metabolic Acidosis in Chicks
Dilger, Ryan N., Baker, David H. 
Journal of Nutrition Sept. 2008; 138: 1628-1633

Link to Abstract

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