Liquid chromatography/quadrupole ion trap/time-of-flight determination of the efficacy of drug test kits for rapid screening of food.
The goal of this study was to evaluate the plausibility and accuracy of commercially available on-site immunoassay urinalysis kits for the screening of compounds of interest within food matrices. In conjunction with this study, a sensitive, robust, and reproducible analytical method, utilizing solid-phase extraction liquid chromatography/quadrupole ion trap/time-of-flight mass spectrometry for confirmation analysis, was developed. The food matrices analyzed were tomato juice, apple juice, milk, beer, white wine, ground beef, powdered milk, and all-purpose flour. Compounds fortified into the food matrices included heroin, phencyclidine, cocaine, benzoylecgonine, methadone, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine, imipramine, doxepin, nitrazepam, diazepam, oxazepam, temazepam, alprazolam, flunitrazepam, clonazepam, and lorazepam. Standard curves were prepared for each matrix from 10 to 500 ng/ml for each analyzed compound. All liquid chromatography/tandem mass spectrometry samples were fortified with 20 microl of deuterated internal standard at 90 ng/ml. Quality control standards were prepared at 20 and 400 ng/ml, and > 90% were within 2 SD of the mean for each analyte. The test kits were found to produce up to 85% of the expected results based on concentration levels of adulterants (i-Screen in milk). This study shows that lateral-flow immunoassay test kits are plausible as a rapid, accurate, and reliable screening method in the event of adulteration of the food supply.
Commonwealth of Virginia, Division of Consolidated Laboratory Services, Richmond, Virginia 23219, USA.
Jessica B
JB
Zuckschwerdt
Christopher E
CE
Nixon
Frederic L
FL
Ciner
Timothy R
TR
Croley
D023482:Bioterrorism; D002853:Chromatography, Liquid / Q000379:methods; D003257:Consumer Product Safety; D004350:Drug Residues / Q000032:analysis*; D005506:Food Contamination / Q000032:analysis*; D008401:Gas Chromatography-Mass Spectrometry / Q000379:methods; D006801:Humans; D007118:Immunoassay; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D052616:Solid Phase Extraction / Q000379:methods
D011933:Reagent Kits, Diagnostic