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General Unknown (From Introduction to Forensic Toxicology, P 169-181, 1981, Robert H Cravey and Randall C Baselt, ed. - See NCJ-89875)

NCJ Number
89878
Author(s)
M Stajic
Date Published
1981
Length
13 pages
Annotation
The 'general unknown' is the last resort for a toxicologist when no pertinent information is available to point the analysis in a particular direction. The most common approach to this type of analysis is the performance of comprehensive screening tests which will isolate for analysis one or more specific drugs.
Abstract
The choice of screening method and its sequence and combination vary from one laboratory to another, depending on the available specimens, the toxins most commonly encountered in a certain region, and other factors. A general scheme for the general unknown analysis is outlined. Direct screening techniques are performed with little or no previous preparation of the biological samples. They include spot tests and immunological methods, such as enzyme multiplied immunoassay technique and radioimmunoassay. Separation techniques, such as distillation and liquid-liquid extraction techniques, and detection techniques, such as ultraviolet spectrophotometry, are described. A few tables and charts and about 30 references are supplied.