Amphetamines are controlled substances which are potent stimulants that induce feelings of strength and energy while decreasing the need to sleep or eat. The majority of illegal amphetamine products are racemic; consequently, both isomers will appear in the biological fluids unchanged. In comparison the break-down products formed by the metabolism of most pharmaceutical drugs show the appearance of pure amphetamine enantiomers. Circular dichroism is a form of light absorption spectroscopy that measures the difference in absorbance of right- and leftcircularly polarized light (rather than the commonly used absorbance of isotropic light) by a substance. Since different enantiomers absorb different portions of the light, it provides and excellent means for enantiomer detection. In this application CD will be used to study the isomers of amphetamine and methamphetamine.

Introduction Near-Infrared (NIR) spectroscopy has unique capabilities as compared to mid-infrared analysis which can often require extensive sample preparation to obtain an identifiable spectrum. As such, NIR can be useful for the non-destructive analysis of a specific sample area or provide an average of a larger sample area, depending upon the required analysis. In recent years, NIR spectroscopy has been widely used for the examination of biological samples and quality control/analysis of food and medical products. The diffuse reflectance technique is ideal for this method due to extremely simple sample handling such that rapid identification of illegal drugs, such as MDMA, can be accomplished by using a search data library created using NIR diffuse reflectance.

The use of near-infrared (NIR) spectroscopy in the pharmaceutical industry has grown rapidly in the past decade. The IMV-4000 Infrared Multichannel Viewer integrated with a NIR capable FT/IR- 4000 or FT/IR-6000 instrument enables NIR Imaging of pharmaceutical tablets, a valuable tool in the estimation of tablet properties, offering measurement data with high specificity and sensitivity. The obtained data can be exported into the Principal Component Analysis (PCA) software for the estimation of tablet characteristics. Instrument: FTIR-6200 with IMV-4000 CaF2 beam splitter, NIR source, etc

The Stopped Flow method is used to analyze reactions occurred during the duration of several milliseconds and several seconds meanwhile the CD measurement provides valuable information regarding the protein’s secondary structures and environment of aromatic amino acids. Therefore, CD measurement with Stoppedflow method provides one of the best techniques in analyzing the protein’s Unfolding and Refolding process. Concanavalin A (derived from Jack bean) in natural state has abundant β-sheet structures, however, it is known that its structure changes into the one with rich α-helix under trifluoroethanol (TFE) and its Unfolding process has been reported also. In this application, the model SFS-492 High-Speed Stopped-flow System was used to measure the Unfolding process of Concanavalin A under TFE. The Concanavalin A’s in pH2 hydrochloric acid gives a CD spectrum specific to β-sheet structure. In contrast, in a solution with 50% of TFE added it has a CD spectrum specific to α-helix structures. As seen in Figure 1, a big change from abundant β-sheet