Tocopherols and tocotrienols are forms of vitamin E that have antioxidative properties. γ-Tocopherol is the most abundant form of vitamin E in the diet. Its metabolite, γ-CEHC (2,7,8-trimethyl-2-(β-carboxyethyl)-6-hydroxychroman), is produced in the liver by the action of cytochrome P450 enzymes and excreted in urine at levels that exceed all other tocopherol metabolites. In plasma, γ-tocopherol has the ability to trap nitric oxide radicals, and both γ-tocopherol and γ-CEHC inhibit cyclooxygenase activity in macrophages and epithelial cells. Thus, the concentration of γ-tocopherol in plasma could be indicative of events related to cardiovascular disease and cancer. Cayman’s γ-CEHC EIA Kit (plasma and serum) is a competitive assay that can be used for efficient quantification of γ-CEHC in plasma and other sample matrices. The EIA typically displays an IC₅₀ (50% B/B₀) of approximately 900 pg/ml and a detection limit (80% B/B₀) of approximately 150 pg/ml.

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