Abstract
Eleven commonly used antihistamines, nonsteroidal anti-inflammatory drugs, and vitamins were evaluated in vitro for potential interference with DRI® and TDx® immunoassay reagents for opiates and amphetamines. Mechanisms for the observed interference were also explored. DRI® reagents appear to be more susceptible to interference by the compounds studied. Regarding mechanistic aspects, tolmetin was found to be strongly absorbent at the detection wavelength (340 nm) causing a false negative response; diphenhydramine, pheniramine, and trimethobenzamide appeared to cause false positive interference through their affinity to the antibodies used in the DRI® reagents; while chlorpromazine was found to positively interfere with the assay through both cross reaction and UV absorption. Ascorbic acid, when in high concentrations (>2%, w/v), may inhibit the enzyme (G6PDH) activity and result in a false negative response.
Original language | English |
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Pages (from-to) | 259-268 |
Number of pages | 10 |
Journal | Journal of Food and Drug Analysis |
Volume | 7 |
Issue number | 4 |
Publication status | Published - Dec 1999 |
Keywords
- Immunoassay
- In vitro
- Interference
- Methamphetamine
- Morphine
ASJC Scopus subject areas
- Food Science
- Pharmacology