ADH Assay
Definition
Alcohol dehydrogenase enzymatic assay. Ethanol plus NAD+ gives acetaldehyde plus NADH; NADH absorbance at 340 nm is proportional to ethanol concentration. Fast hospital and screening method.
- Enzyme
- Alcohol dehydrogenase
- Cofactor
- NAD+
- Product measured
- NADH
- Detection wavelength
- 340 nm
- Typical use
- Fast hospital and screening method
Common questions
Why isn't the ADH assay usually the sole evidentiary method in court?+
It is an enzymatic screen sensitive to interference from other reducing substances in the sample, so results are generally confirmed by a chromatographic method such as headspace GC before being relied on as evidence.
What sample types is the ADH assay commonly run on?+
It is typically applied to serum or plasma in hospital settings for a fast clinical readout, distinct from the whole-blood GC methods used for evidentiary blood alcohol determination.
Related terms
- BAC
- Blood Alcohol Concentration. Mass of ethanol per unit volume of whole blood. Indian legal cut-off is 30 mg per 100 mL (0.03...
- Fuel-Cell Breath Analyser
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- Headspace GC-FID
- Gas chromatography with flame ionisation detection on the vapour above a heated sealed vial. Gold-standard quantitative method for ethanol in blood, urine,...
- IR Breath Analyser
- Infrared absorption at about 3.4 micrometres (C-H stretch) or 9.5 micrometres (C-O stretch). Specific and quantitative; used in Intoxilyzer 8000 and evidential...
- Putrefactive Ethanol
- Ethanol produced post-mortem by microbial fermentation of glucose, lactate and amino acids. Can give false-positive BAC; vitreous humor is the matrix of...
- Wet-Bath Simulator
- Calibration accessory holding a 0.10 g per L aqueous ethanol solution at 34 degrees Celsius. The vapour above gives a known reference...
- Widmark Formula
- A = r × W × C, where A is total alcohol in body (g), W is body weight (kg), C is...