Specific Organic Compounds as Impurities in Official Pharmaceutical Substances

DETERMINATION OF SPECIFIC ORGANIC COMPOUNDS AS IMPURITIES IN OFFICIAL PHARMACEUTICAL SUBSTANCES 

A number of organic compounds, such as N, N-dimethylaniline-present in amoxycillin trihydrate cephalexin cloxacillin sodium dicloxacillin sodium 2-ethylhexanoic acid-in amoxycillin sodium 4-chlorophenol-in clofibrate acetone and butanol-in daunorubacin hydrochloride cineole limonene ratio-in dementholised mint oil etc  

Materials Required Cephalexin sample 1.0 g Solution A [0.005% w/v soln. of naphthalene (internal standard) in cyclohexane] 20 ml Solution B (mix 50 mg of N, N-dimethylaniline with 2 ml HC1 and 20 ml of water, shake to dissolve, add enough DW to produce 50 ml and dilute 5 ml of the resulting solution to 250 ml with DW) 20 ml solution (1) (add 5 ml of 1 M NaOH and 1 ml of solution A to 1 ml of solution B, shake vigorously for 1 minute, centrifuge and use the upper layer) solution (2) (dissolve 1 g of cephalexin sample in 5 ml of 1 M NaOH, add 1 ml of solution A, shake vigorously for 1 minute, centrifuge and use the upper layer)  

Column Glass column size (2 M 2 mm) adsorbent packed with acid-washed, silanized diatomaceous support (80 to 100 mesh) impregnated with 3% w/w of phenyl methyl silicone fluid (50% phenyl, and maintained at 120 °C, 

Procedure After having set the above experimental conditions for gas chromatography, inject 1 pi of the solutions (1) and (2) sequentially into the column. Repeat the determinations so as the ensure a consistent response. Determine the peak areas.  

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Determination of specific organic compounds as impurities in official pharmaceutical substances... 

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