Sedatives sample preparation

Fig. 3 Scanning electron microscopy (SEM) of (A) a freeze-dried lysozyme sample and (B) the same sample prepared via SEDS. (From Ref. l)...

Although clinically prescribed as sedatives and anticonvulsants, benzodiazepines can be abused and therefore must be monitored in drug tests. Many GC-MS methods are currently available for the analysis of benzodiazepines [46-50]. Recent advances have been made with regards to preanalysis enzyme hydrolysis [46,48], analysis of the drugs in human tissue [47], and the investigation of new sample preparation techniques [49]. A good review of numerous techniques currently used to analyze benzodiazepines was published by Drummer [50]. 

Procedure. The three materials are stirred together and boiled under reflux (130°) for three hours. After cooling to 50°, 500 ml. of water is added and the mixture is steam distilled to recover 42 g. of 2-chloro-thiophene. The heavy oil may l>e worked up, as in the case of 2-acetyl-thiophene, by washing with water and 10% sodium carbonate. Benzene may be u.sed as a solvent if desired. The product is distilled from a Claisen flask, b.p. 88° at 4 mm., whereupon it crystallizes. An analytical sample is prepared by recrystallization from water and alcohol, m.p. 46.5-47°. 

Figure 9. Flow diagram (starting at an idealised sediment core) for the preparation of lacustrine sediment samples for the isotopic analysis of organic matter, emphasising the importance of integrating such studies with a range of other analytical techniques. Based in part on procedures u.sed by the International Decade for the East African Lakes (IDEAL) project (LRC, 1999).

Figure 24 Effect of shear force on dispersion of a micronized and SEDS-prepared sample of salmeterol xinafoate. (From Ref. 85.)...

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