Identification Tests Tartrate

Metaprolol tartrate tablet testing uses UV and IR spectroscopy for metaprolol ID, TLC for the tartrate ion ID, and HPLC retention time for identification. The IR spectroscopy test is carried out by dissolving approximately 136 mg of finely ground tablets and in 25 mL of water with 4 mL of ammonium hydroxide (1 3). After extraction with chloroform, the organic layer is dried over anhydrous sodium sulfate, evaporated, and placed in a freezer to congeal... 

The British Pharmacopoeia, 1948 revision, includes standards for total ash, acid-insoluble ash, and starch and foreign organic matter. It requires certain identification tests— for instance, that no pink color is produced when tragacanth is treated with ruthenium red and that the characteristic copper reduction of alkaline copper tartrate solutions is produced to indicate the sugar character of the gum. 

Derivatives. The precise identification of a compound normally depends upon the preparation of a derivative and the determination of physical constants such as m.p. in the case of a solid. Many simple compounds can, however, be identified with a fair degree of certainty by intelligently-selected qualitative tests alone, e.g., formates, oxalates, succinates, lactates, tartrates, chloral hydrate. 

Identification A sample gives positive tests for Sodium and for Tartrate, Appendix IIIA. 

The selectivity of the method is given first by the ability to stay dissolved in a solution containing tartrate, second by the color of the sulfide precipitate, and finally by the fact that the sulfide salt dissolves in sodium hydroxide. The first property distinguishes it from bismuth(III) and the other cations forming insoluble oxides in neutral or alkaline solutions. But since the test does not show that a precipitate is formed in pure water, which dissolves when tartrate is added, all water-soluble cations are not excluded. So it should be viewed as a trick to facilitate dissolution only and not a part of the identification. The color of the sulfide precipitate is unique, and it is the most important criterion for a positive identification if there is any doubt when judging the result, preparing a positive control would be constructive. The solubility of the sulfide salt in sodium hydroxide is a characteristic shared with, for example, the sulfide salt of arsenate, and in classic inorganic separation the sulfide precipitate solubility in hydrochloric acid or polysulfide is used instead. " ... 

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