Simple and Robust Analysis of Cefuroxime in Human Plasma by LC-MS/MS: Application to a Bioequivalence Study

Abstract

A simple, robust LC-MS/MS assay for quantifying cefuroxime in human plasma was developed. Cefuroxime and tazobactam, as internal standard (IS), were extracted from human plasma by methanol to precipitate protein. Separation was achieved on a Zorbax SB-Aq (4.6 × 250 mm, 5 μm) column under isocratic conditions. The calibration curve was linear in the concentration range of 0.0525–21.0 μg/mL (r = 0.9998). The accuracy was higher than 90.92%, while the intra- and interday precision were less than 6.26%. The extraction procedure provides recovery ranged from 89.44% to 92.32%, for both analyte and IS. Finally, the method was successfully applied to a bioequivalence study of a single 500 mg dose of cefuroxime axetil in 22 healthy Chinese male subjects under fasting condition. Bioequivalence was determined by calculating 90% Cls for the ratios of C max, AUC0−t, and AUC0−∞ values for the test and reference products, using logarithmic transformed data. The 90% Cls for the ratios of C max (91.4%~104.2%), AUC0−t (97.4%~110.9%), and AUC0−∞ (97.6%~111.1%) values were within the predetermined range. It was concluded that the two formulations (test for capsule, reference for tablet) analyzed were bioequivalent in terms of rate and extent of absorption and the method met the principle of quick and easy clinical analysis.

Quantification of total and unbound cefuroxime in plasma by ultra‐performance liquid chromatography tandem mass spectrometry in a cohort of critically ill patients with hypoalbuminemia and renal failure

“…After centrifugation at 1500 g for 25 min at 25°C, 0.1 mL of the filtrate was processed and unbound cefuroxime was quantified as described in Section 2.2. Stability data (25°C for 25 minutes) were adopted from Hu and colleagues . The unbound fraction concentration was expressed as (total measured concentration – protein‐bound concentration)/ total measured concentration.…”

“…Leftover plasma samples were collected at room temperature (15‐25°C) in serum tubes as part of routine patient care. Samples were centrifuged after collection and frozen at −20°C for a maximum of six months to analysis . Samples were analyzed batch‐wise.…”

“…Stability of plasma samples was not tested. Stability data of cefuroxime plasma samples were adopted from Hu and colleagues where corresponding storage times and temperatures (6 months at −20°C) were used …”

“…Stability data (25°C for 25 minutes) were adopted from Hu and colleagues. 10 The unbound fraction concentration was expressed as (total measured concentration -protein-bound concentration)/ total measured concentration.…”

“…Samples were centrifuged after collection and frozen at −20°C for a maximum of six months to analysis. 10 Samples were analyzed batchwise. Stability of plasma samples was not tested.…”