Trace Level Determination of p-Toluidine in Penem Drug Substances by Gas Chromatography

Abstract

A Gas chromatographic method using flame ionization detector (GC-FID) has been
developed and validated for the quantitative determination of p-Toluidine in
Meropenem trihydrate, Imipenem monohydrate, Doripenem monohydrate and
Ertapenem monosodium pharmaceutical drug substances. The chromatographic method
was achieved on fused silica capillary column (Rtx-5) with 5% diphenyl and 95%
dimethyl polysiloxane stationary phase. The detection and quantitation limits obtained
for p-Toluidine were 0.9 µg g-1 and 2.7 µg g-1 respectively. The relative standard
deviation for analyte response was found as 0.9% for six replicate injections of standard
equivalent to 100 µg g-1 of p-Toluidine. The average recoveries of p-Toluidine in
Meropenem trihydrate, Imipenem monohydrate, Doripenem monohydrate and
Ertapenem monosodium were obtained 99.6%, 99.2%, 96.7% and 107.9% respectively.
The method was found to be linear in the range between 2.7 and 150 µg/g with a
correlation coefficient 0.9999. The developed method was found to be robust for the
determination of p-Toluidine in Penem drug substances.