Derivatization with carbon disulfide

Table 2.3 GC operating conditions and parameters suitable for the analysis of amphetamine derivatized with carbon disulfide...

In order to alleviate this problem, derivatization can be employed. One of the easiest processes, for the analysis of amphetamine, is to derivatize directly with carbon disulfide and it is this method which finds wide application in the United Kingdom. For bulk and trace samples, this is achieved by dissolving the material... 

Many of the biologically important -phenylalkyl-amines and also indolylalkylamines contain alcoholic and/or phenolic hydroxyls. For a separation by GC, these polar groups must be derivatized. This can be done by silylation. We use a one-step method [49], Both reagents, carbon disulfide and the silylating agent (usually trimethylsilylimidazole), are added to a solution of the amine in a polar solvent such as dimethylforma-mide or pyridine. A two-step procedure has also been described [56, 57]. The free bases are dissolved in ethyl acetate and treated with carbon disulfide, the solution is evaporated to dryness, and mustard oil is dissolved in pyridine and silylated at 100 °C. If the reaction time is sufficiently long, this procedure also silylates the indole nitrogen. Trifluoroacetylation has also been used to block the hydroxyls of the mustard oils [60]. 

Lack of response to water and carbon disulfide allows these to be used as solvents without interference with the analysis Good for electronegative compounds such as those containing extensively conjugated pi-electron systems, nitro- and highly conjugated aromatic compounds and compounds which can be readily derivatized to respond. " Response depends also upon carrier gas flow rate... 

Acidify sample with citric acid adjust to pH 9.5 with NaOH extract with diethyl ether wash with sodium bicarbonate dry with anhydrous sodium sulfate evaporate and redissolve in acetone evaporate fractionate using TLC remove region of silica gel containing MBOCA and extract with acetone evaporate derivatize with TFA evaporate and reconstitute in triphenyl-amine in carbon disulfide... 

The viscose process was discovered by Cross, Bevan and Beadle in 1892. By treating cellulose with caustic soda and then carbon disulfide (CS2), they were able to dissolve the derivatized cellulose in water or dilute caustic soda to form cellulose xanthate. The solution was then extruded through a spinneret into a coagulation bath containing sulphate/sulphuric acid and water. The as-spun fibers were then neutralized and regenerated to cellulose form... 

The chemical modification by silani2a-tion (or other chemical reactions) of carbon, oxide, or metal electrode surfaces [21, 22] or SAM formation on gold surfaces with thiol or disulfide compounds [23] has been utilized for the tip functionalization. The systematic chemical derivatization of the tips was carried out with silane [10, 24-27] or thiol [17, 18, 20, 28-37] derivatives. Today, chemical differentiation of the terminal groups by FFM [5-20,28, 36, 37] or adhesive force measurements [17, 18, 20, 24-28, 30-37] is called chemical force microscopy (CFM) [17]. Adhesive and frictional forces can be mapped in x-y planes as CFM images. The adhesive... 

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