Matrix effect and cross-reactivity of select amphetamine-type substances, designer analogues, and putrefactive amines using the Bio-Quant direct ELISA presumptive assays for amphetamine and methamphetamine.
The aim of this study was to evaluate the Bio-Quant Direct ELISA assays for amphetamine and methamphetamine in the routine presumptive screening of biological fluids. Standard concentration curves of the target analytes were assayed to assess sensitivity, and known concentrations of common amphetamine-type substances (ephedrine, pseudoephedrine, phentermine), designer analogues (MDA, MDMA, MDEA, MBDB, PMA, 4-MTA, 2CB), and putrefactive amines (phenylethylamine, putrescine, tryptamine, tyramine) were analyzed to determine cross-reactivity. Results of the standard curve studies show the capacity of both Direct ELISA kits to confidently detect down to 3 ng/mL interday (PBS matrix; CVs 6.3-15.5%). Cross-reactivity relative to that of 50 ng/mL preparations of the target compounds demonstrated that the Direct ELISA kit for amphetamine also detected MDA (282%), PMA (265%), 4-MTA (280%), and phentermine (61%), and the Direct ELISA for methamphetamine also assayed positive for MDMA (73%), MDEA (18%), pseudoephedrine (19%), MBDB (8%), and ephedrine (9%). Matrix studies demonstrated that both ELISA kits could be applied to screening of blood, urine, and saliva to a concentration of 6 ng/mL or lower. In conclusion, the Bio-Quant Direct ELISA kits for amphetamine and methamphetamine are fast and accurate and have demonstrated themselves to be useful tools in routine toxicological testing.
Apollonio
Luigino G
LG
National Centre for Forensic Studies, University of Canberra, Bruce ACT 2601 Australia. Luigino.Apollonio@canberra.edu.au
Whittall
Ian R
IR
Pianca
Dennis J
DJ
Kyd
Jennelle M
JM
Maher
William A
WA
D000588:Amines / Q000032:analysis* / Q000097:blood / Q000276:immunology / Q000652:urine; D000661:Amphetamine / Q000032:analysis; D000662:Amphetamines / Q000032:analysis* / Q000097:blood / Q000276:immunology / Q000652:urine; D000906:Antibodies; D000918:Antibody Specificity; D003429:Cross Reactions; D015198:Designer Drugs / Q000032:analysis*; D004797:Enzyme-Linked Immunosorbent Assay; D005554:Forensic Medicine / Q000379:methods*; D006801:Humans; D008694:Methamphetamine / Q000032:analysis; D011180:Postmortem Changes; D011933:Reagent Kits, Diagnostic; D015203:Reproducibility of Results; D012463:Saliva / Q000737:chemistry; D012680:Sensitivity and Specificity; D015813:Substance Abuse Detection / Q000379:methods*
D000588:Amines; D000662:Amphetamines; D000906:Antibodies; D015198:Designer Drugs; D011933:Reagent Kits, Diagnostic; D008694:Methamphetamine; D000661:Amphetamine