Methods, compositions and apparatuses for detection of gamma-hydroxybutyric acid (ghb)

Abstract

Methods, compositions and articles of manufacture for assaying a sample for a GHB source are provided. A sample suspected of containing a GHB source is contacted with a first oxidoreductase selective for GHB and an oxidized cofactor. In the presence of GHB in the sample, the first oxidoreductase oxidizes GHB to succinic semialdehyde and reduces the cofactor. The reduced cofactor thus produced can be detected directly, or a hydride abstractor can be used that abstracts a hydride from the reduced cofactor and produces a detectable change. The hydride abstractor can be a second oxidoreductase that oxidizes the reduced cofactor and produces a detectable change in a chromogen or dye. Preferably a visual change is produced, allowing performance of the assay outside of a laboratory setting. Fusion proteins comprising the first oxidoreductase, polynucleotides encoding such proteins, host cells expressing such proteins, and vectors comprising such polynucleotides are also provided. Stabilized formulations of the first oxidoreductase are also provided. Test supports, devices, and compositions and kits comprising reagents for performing such methods are also provided. Techniques for performing the assay in the presence of ethanol and in the presence of GHB precursors in the sample are also provided.