ABSTRACT
We developed a rapid, sensitive, and simple-to-use multi-analyte diagnostic device for the detection of drugs of abuse in urine: the ONTRAK TESTCUP. No sample or reagent handling is necessary with this device, and the device also serves as the sample collection cup. The TESTCUP contains immunochromatographic reagents that qualitatively and simultaneously detect the presence of benzoylecgonine, morphine, and cannabinoids (delta9-tetrahydrocannabinol [THC] in urine. It is based on the principle of competition between the drug in the sample and membrane- immobilized drug conjugate for antidrug antibodies coated on blue-dyed microparticles. Each drug assay has its own strip, which contains an antibody specific to benzoylecgonine, morphine, or THC. A sample is collected in the TESTCUP, a lid is placed on it, and a chamber at the top of the cup is filled with urine by inverting the cup for 5 s. Urine proceeds down immunochromatographic strips, and the assays are developed. In approximately 3-5 min, the Test Valid bars appear, a decal is removed from the detection window, and the results are interpreted. The appearance of a colored bar at the detection window for each drug indicates a negative result. The absence of color in any specific drug detection window indicates a positive result for that drug. If a positive result is obtained, the same device (cup) can be used for gas chromatographic-mass spectrometric (GC-MS) confirmation. When the precision of the TESTCUP was evaluated, the results obtained were as follows: for urine controls containing drug at 50% of its cutoff concentration, the results were greater than or equal to 96, 98, and 96% negative for benzoylecgonine, morphine, and THC, respectively; for urine controls containing drug at 120% of its cutoff concentration, the results were greater than or equal to 97, 100, and 98% positive for benzoylecgonine, morphine, and THC, respectively. The correlations of clinical sample results using the TESTCUP versus results by GC-MS and the ONTRAK and OnLine assays were assessed. There was 100% agreement between samples prescreened positive by GC-MS and positive by TESTCUP for all three assays. There was 100% agreement between TESTCUP and ONTRAK results and between TESTCUP and OnLine results when testing clinical samples positive and negative for cocaine (benzoylecgonine) or THC. Greater than 99% agreement was observed between TESTCUP and ONTRAK results and between TESTCUP and OnLine results when testing clinical samples positive and negative for morphine. The cross-reactivity of the TESTCUP assay to related drugs and drug metabolites was also determined, and the results were similar to those of the ONTRAK and OnLine assays.
Subject(s)
Illicit Drugs/urine , Substance Abuse Detection/instrumentation , Substance Abuse Detection/methods , Cocaine/analogs & derivatives , Cocaine/analysis , Cocaine/urine , Dronabinol/analysis , Dronabinol/urine , Gas Chromatography-Mass Spectrometry , Humans , Illicit Drugs/analysis , Immunoassay , Morphine/analysis , Morphine/urine , Online Systems/standards , Reference Standards , Reproducibility of ResultsSubject(s)
Eye/radiation effects , Lasers , Adult , Animals , Eye Injuries/etiology , Female , Haplorhini , Humans , Lasers/adverse effects , Male , Models, Theoretical , Rabbits , Radiation Injuries/etiologyABSTRACT
The mechanism of peroxidase-catalysed oxidation of luminol by H2O2 was studied. The stopped-flow technique was used to measure the rate constants for the reactions between the oxidized forms of peroxidase with luminol and the following substrates: p-iodophenol, p-bromophenol, p-clorophenol, o-iodophenol, m-iodophenol, luciferin, and 2-iodo-6-hydroxybenzothiazole. The correlation between kinetic parameters and the degree of enhancement was established. The effect of charged synthetic polymers and specific antibodies on the peroxidase activity in the enhanced chemiluminescent reaction was also studied. The close approach of an effector molecule to the active site of the enzyme was found to inhibit the enhanced chemiluminescent reaction. Novel homogeneous methods of luminescent immunoassay (LIA) for (1) antibodies to insulin, (2) insulin and (3) antibodies to trinitrophenyl group are proposed on the basis of regulatory facilities of the enhanced chemiluminescent reaction. Based on the enhanced chemiluminescent reaction a peroxidase flow-injection assay was developed and successfully tested in the flow-injection enzyme immunoassays for human IgG and for thyroxin (T4). The immunoassay proposed has a detection limit of 10(-9) M for IgG and 10(-11) M for T4, the overall time of the assay being 5-15 min.
