Published: Journal of Analytical Toxicology, Volume 23, Number 1, January/February 1999, pp. 11-16.
Highly Sensitive Quantitation of Methamphetamine by
Time-Resolved Fluoroimmunoassay Using a
New Europium Chelate as a Label
A simple and highly sensitive time-resolved fluoroimmunoassay of methamphetamine (MA) using a new fluorescent europium chelate (BHHCT-Eu3+) as a label is described. Two variations of competitive immunoassay were attempted. In the first (one-step) assay, microtiter plates coated with anti-MA were used, and the new label was bound to a conjugate of bovine serum albumin and N-(4-aminobutyl)-MA (MA-BSA). In the second (two-step) assay, instead of the labeled MA-BSA, biotinylated MA-BSA and BHHCT-Eu3+-labeled streptavidin-BSA were used. The lowest measurable concentrations of MA for the one-step and the two-step methods were 1 ng/mL (25 pg/assay) and 1 pg/mL (25 fg/assay), respectively. These were 10 to 1000 times superior to the detection limits of MA in any other immunoassay. Intra-assay coefficient of variation was approximately 2–8% at eight different concentrations (n = 4). Analysis of 34 urine samples with the new method and conventional gas chromatography showed a good correlation (r = 0.954). The high detectability of the present assay also enabled segmental hair analysis with a few centimeters of a hair.
Reproduction of editorial content of this journal is prohibited without publisher’s permission.
| This article is available in its entirety by fax for $40.00 each. Visa, MasterCard and AMEX accepted. To order electronically click
here Please indicate JAT volume and issue along with page numbers. |
| Home | Subscribe | Current Issue | Back Issues | Search | Advertise | Other Publications | Site Map |