Specific High-Performance Liquid Chromatographic Determinatioin of Ampicillin in Bulks, Injectables, Capsules, and Oral Suspensions by Reverse-Phase Ion-Pair Chromatography

Abstract

Abstract A rapid, specific, stability-indicating high-performance liquid chromatographic (HPLC) method has been developed for the assay of Ampicillin in Ampicillin Trihydrate bulk, capsules and oral suspensions and Sodium Ampicillin bulk and injectables. The assay is specific for Ampicillin in the presence of possible contaminants; Penicillin V, Phenylglycine, and 6-Aminopenicillanic Acid (6-APA); the degradation product, Penicilloic Acid of Ampicillin; and all excipients present in the formulations assayed. Ampicillin, Ampicillin formulations, and formulation excipient blends were force-degraded to further demonstrate specificity. The assay is precise, accurate, linear over the range 50% to 125% of expected Ampicillin sample level, and stability-indicating toward the described thermal, acid, base, aqueous, and light degradations. The procedure employs an ion-pairing eluent with UV detection at 254 nm. Ampicillin Trihydrate and Sodium Ampicillin bulk are stable in assay diluent for six hours allowing the use of automatic HPLC injectors for unattended analysis. One set of HPLC parameters can assay bulks and formulations.