Development of an ultraviolet spectrophotometric method for the determination of ceftiofur sodium powder.

A UV spectrophotometric method was developed for determination of ceftiofur sodium in the drug substance and sterile powder for injection. The method validation, which yielded good results, included evaluation of the range, linearity, intra- and interday precision, accuracy, recovery, specificity, robustness, LOQ, and LOD. The UV spectrophotometric determinations were performed at 292 nm. Good linearity was obtained between 2.5 and 20.0 microg/mL. A prospective validation showed that the method is linear (r = 0.9999) and precise, with RSD values of 0.3% for product A and 0.4% for product B. The intra- and interday precision values were < 2% for all samples analyzed. Comparison of UV spectrophotometry and LC by analysis of variance and Student's t-test showed no significant difference between methodologies. Moreover, the accuracy and precision obtained with the UV method correlated well with the values obtained with the LC method, and this correlation suggests that UV spectrophotometric analysis can be an inexpensive, reliable, and less time-consuming alternative to chromatographic analysis. The results demonstrated the validity of the proposed method as a simple and useful alternative for the determination of ceftiofur in routine QC analyses.

Development of a microbiological assay to determine the potency of ceftiofur sodium powder.

Ceftiofur sodium is a third-generation broad-spectrum cephalosporin antibiotic, formulated as an intramuscular injection, that is approved for use in pigs, cattle, poultry, and dogs. The present work reports a method to quantify ceftiofur in powder for injection by comparing the cylinder plate assay and the liquid chromatographic (LC) method. The assay is based on the inhibitory effect of ceftiofur upon the strain of Micrococcus luteus ATCC 10240 used as the test microorganism. Ceftiofur sodium at concentrations ranging from 2.0 to 8.0 microg/mL can be measured in powder for injection. A prospective validation showed that the method is linear (r2 = 0.9998), with precise relative standard deviation (RSD) of 0.8% for product A (Excenel; Pharmacia and Upjohn Co., Kalamazoo, MI) and of 0.6% for product B (Topcef; Eurofarma Lab. Ltda, São Paulo, Brazil), with intermediate precision; between-day RSD = 1.0 and 1.1%, between-analyst RSD = 0.8 and 0.8% for products A and B, respectively and accurately. The comparison between bioassay and LC by analysis of variance and Student's t-test showed no significant difference among methodologies. The results demonstrated the validity of the proposed bioassay that is simple and a useful alternative methodology for analysis of ceftiofur in routine quality control.