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Department of Forensic Sciences
DRUG CHEMISTRY: PRESUMPTIVE METHODOLOGIES

Pharmaceutical Identifiers

Commercially prepared pills, tablets, and manufactured sealed capsules possess unique pharmaceutical identifier information both in the general appearance and inscriptions/markings of the pharmaceutical preparation. Pharmaceutical identifiers are utilized to separate visually consistent populations of commercially prepared pills, tablets, and manufactured sealed capsules for analysis.


Macroscopic/Microscopic Examination

The presumptive identification of marihuana is based upon a visual exam (macroscopic/microscopic) of submitted plant material for botanical characteristics present in the marihuana plant.


Microcrystalline Tests

A microcrystalline test is a presumptive test in which there is a chemical reaction (precipitation reaction) between a substance and a reagent that yields a crystal formation that can be observed microscopically.

The major advantages of a microcrystalline test are: rapid and simple procedure, high sensitivity, can be conducted on unextracted samples, can be utilized to distinguish isomers of certain drugs, and crystals formed are actual crystals of the drug.


DART-TOF Mass Spectrometry (Preferred Method)


Direct analysis in real time (DART) is an open air ionization technique. The open air source allows sampling of solids, liquids, and gases through surface ionization of the test material. The ion source is coupled to an accurate time-of-flight mass spectrometer giving quick analysis of molecular ions with little to no sample preparation.