title: Dual-label time-resolved fluoroimmunoassay of psychopharmaceuticals and stimulants in serum.
abstract: A new method to measure two different drugs simultaneously by time-resolved fluoroimmunoassay (TR-FIA) has been developed. In the TR-FIA reported here, psychopharmaceuticals [chlorpromazine (CPZ) and desipramine (DSP)] and methamphetamine (MA) contained in serum are assayed by a combined use of a new europium (Eu) chelate and a samarium (Sm) chelate, as labels. The drug concentrations were determined by the competition between a labeled antigen with Eu(3+) or biotin and a sample antigen. A microtiter plate coated with a mixture of rabbit IgGs (anti-MA and anti-CPZ or anti-MA and anti-DSP) was used. In the assay of MA and CPZ, Eu(3+) labeled MA-bovine serum albumin conjugate (MA-BSA) and biotinylated CPZ-BSA were added to the well with their non-labeled standard solutions or samples. MA was assayed by measuring the fluorescence intensity of Eu(3+) at 615 nm. After incubation of the Sm(3+) labeled streptavidin, CPZ was assayed by measuring the fluorescence of Sm(3+) at 643 nm. In the assay of MA and DSP, Eu(3+) labeled DSP-BSA and biotinylated MA-BSA were used. In our dual-assay, the minimum detection limits of these drugs were 1ng/ml for MA, 10 ng/ml for CZP and 10 ng/ml for DSP. Since the simultaneous detection of different drugs by TR-FIA is time and sample saving, the method can be employed in rapid and sensitive screening tests.
authors.affiliation: Department of Forensic Medicine, Juntendo University School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Kimura
authors.forename: M
authors.initials: M
authors.lastname: Mukaida
authors.forename: G
authors.initials: G
authors.lastname: Wang
authors.forename: J
authors.initials: J
authors.lastname: Yuan
authors.forename: K
authors.initials: K
authors.lastname: Matsumoto
mesh_terms: D000818:Animals; D000929:Antidepressive Agents, Tricyclic / Q000097:blood*; D014150:Antipsychotic Agents / Q000097:blood*; D002138:Calibration; D000697:Central Nervous System Stimulants / Q000097:blood*; D002746:Chlorpromazine / Q000097:blood*; D003891:Desipramine / Q000097:blood*; D015200:Fluoroimmunoassay / Q000295:instrumentation / Q000379:methods*; D008694:Methamphetamine / Q000097:blood*; D011817:Rabbits; D012680:Sensitivity and Specificity; D015813:Substance Abuse Detection / Q000379:methods*; D014116:Toxicology / Q000379:methods*
chemical_list: D000929:Antidepressive Agents, Tricyclic; D014150:Antipsychotic Agents; D000697:Central Nervous System Stimulants; D008694:Methamphetamine; D003891:Desipramine; D002746:Chlorpromazine