A specific immunoassay for the detection of flunitrazepam.
The development of an immunochemical procedure for the determination of flunitrazepam in whole blood is described. Flunitrazepam was derivatized in position 3 of the benzodiazepine ring to a hapten which was coupled to a carrier protein. To obtain antibodies, rabbits were immunized with these immunogens and the collected antisera were tested in a heterogeneous, competitive RIA. The antibodies showed a very specific reaction with flunitrazepam and hardly any cross-reactivity with related 1,4-benzodiazepines. Because of its high specificity the antiserum has the advantage of a definite determination of low levels of flunitrazepam without the risk of false-negative results obtained by using the commercially available group-specific test systems. The drug was extracted from whole blood in a simple batch process with a polystyrene suspension and the extracts were measured by RIA. The advantages of an immunochemical system, such as short analysis time and simple sample preparation, and the exactness of a drug-specific method are combined in this procedure, which allowed the specific and very sensitive determination of flunitrazepam in the low therapeutic range.
Institut für Rechtsmedizin, Westfälische Wilhelms-Universität, Münster, Germany.
A
A
West
H
H
Köhler-Schmidt
S
S
Baudner
G
G
Blaschke
D000818:Animals; D014151:Anti-Anxiety Agents / Q000097:blood*; D003429:Cross Reactions; D005445:Flunitrazepam / Q000097:blood*; D005554:Forensic Medicine; D006801:Humans; D011817:Rabbits; D011863:Radioimmunoassay / Q000379:methods*; D012680:Sensitivity and Specificity; D015813:Substance Abuse Detection / Q000379:methods
D014151:Anti-Anxiety Agents; D005445:Flunitrazepam