Development and Validation of a Headspace GC–MS Method for Simultaneous Quantification of Antimicrobial Preservatives in Biopharmaceutical Peptide Formulations

Abstract

The four most used antimicrobial preservatives in biopharmaceutical parenteral formulations are phenol, meta‐cresol, chlorobutanol, and benzyl alcohol. Preservatives are included in various combinations in biopharmaceuticals highlighting the importance of an analytical method to quantify the four preservatives simultaneously. A headspace GC–MS method was developed to quantify phenol, chlorobutanol, meta‐cresol, and benzyl alcohol. The method was validated according to USP <1225>. System suitability <USP 621> was conducted daily for retention time (%RSD < 2.0%), peak area (%RSD < 5.0%), USP tailing factor (< 2.0 and %RSD < 10.0%), and peak resolution (> 2.0). Analytical ranges were 1.5–90 μg/mL for phenol and meta‐cresol, 30–240 μg/mL for benzyl alcohol, and 30–300 μg/mL for chlorobutanol. Method accuracy ranged from 94% to 108% and precision from 4% to 15 %RSD for all the tested preservatives. The method was applied to three marketed teriparatide drug products selected as a model. Preservative concentrations of the biopharmaceutical marketed products were determined and were found to be comparable with the labeled concentrations, except for an expired product with 2.5% of the label claim. The developed headspace GC–MS method can be used to evaluate the drug quality of the parenteral formulations and to support the assessment of biopharmaceutical peptide drug products.