Characterization of Resultant Micro Chemical Test Crystalline Formations using Optical, Fourier Transform Infrared (FT-IR) and Raman Microscopies

Micro chemical tests have been used to aid in the identification of materials and as rapid screening tools for microscopists and forensic chemists for decades. It is generally understood in the microscopy community that these types of tests, with unique resultant crystalline formations, can be quite specific and used for material identification. However, some consider micro chemical tests as secondary identification tests, since many of the tests involve the same chemical reagent used for a variety of analytes. Many of these micro chemical tests are used at the FCC in the analysis of forensic evidence to rapidly determine the presence or absence of drugs and other organic and inorganic chemicals. These tests can be very useful in the characterization of dietary supplements, which consist of very complex mixtures. It can be argued that the need for micro chemical tests is becoming less important with the availability of very sensitive instrumental techniques such as mass spectrometry. However, these tests allow for very rapid separation of a heterogeneous mixture, provide sample matrix information and information on the crystallinity of a material. This is especially important for pharmaceuticals, as a difference in drug crystallinity can affect its bioavailability.