Separation and determination of preservative methylparaben in insulin preparations using gas chromatography

الملخص EN

In this se arch an improved gas chromatographic method was used for identification and ty pically quantitated for methy lparaben(mp) which is used as preservative in insulin pre parations.

it was involved the optimal conditions for extraction mp from aqueous samples with ethy l acetate , c hloroform ,and toluene as extractants,then analy zed by gas chromatography(GC).

Effects of eac h of extractants polarity , aqueous samples pH, phases (organic to aqueous) ratio, mixing time , polarity of stationary phase s, and column temperature on efficiency of separation and determination of mp.

were studied in this work.

Sy nthetic sample which containe d the same contents as a life sample was tested to omit interferings of other drug additives on analy sis results.

The extraction of mp.

was (90-91)% with one batch of ethy l ace tate and (99-100)%with two batches of ethy l acetate at pH me dium(1.5-2).

also the non-polar stationary phase(OV-101) is the best choi ce for determining mp by GC.

The conc entration of mp.

in insulin preparations was within the acceptable range(1.003mg/ml).

The relative error (R.E) was ± (0,39-1.49)% and relative standard deviation(R.S.D) was (1.21)% for life sample s.