To demonstrate practical approaches that can be used to significantly improve throughput of the cephradine USP assay monograph keeping to the spirit of USP-NF Chapter <621> guidelines while maintaining USP quality acceptance criteria.

The Thermo Scientific Dionex UltiMate 3000 LC system is applied for the analysis of Cefradine and its impurities. The separation was performed on a Thermo Scientific Hypersil Gold column using the method described in the EP 8.0 monograph. Resolution between cefalexin and cefradine was 7.3 (EP criteria of minimum 4.0). Retention time of cefradine was 15.1 minutes (EP criteria of about 15 minutes). The criteria for relative retention time were also exceeded.

The Thermo Scientific Dionex UltiMate 3000 LC system is applied for the assay analysis of cefalexin. The separation was performed on a Thermo Scientific Acclaim 120 C18 HPLC column using the method described in the EP 8.0 monograph. The results obtained for resolution exceeded the criteria stated in the EP. Resolution between cefalexin and cefradine was 14.1 (EP criteria of minimum of 4.0).

The Thermo Scientific Dionex UltiMate 3000 LC system is applied for the analysis of ampicillin and its impurities. The separation was performed on a Thermo Scientific Acclaim 120 C18 HPLC column using the method described in the EP 8.0 monograph. The results obtained for resolution and relative retention time (RRT) exceeded the criteria stated in the EP. Resolution between ampicillin and cefradine was 3.23 (EP criteria minimum of 3.0). RRT with reference to ampicillin and ampicillin dimer in reference solution (d) was 2.84 (EP criteria about 2.8).

The Thermo Scientific UltiMate 3000 HPLC system is applied for the determination of cephalosporins. The separation is performed on a Thermo Scientific Syncronis C18 HPLC column, with UV detection at 254 nm.