Development and validation of a novel HPLC/ELSD method for the direct determination of tobramycin in pharmaceuticals,plasma, and urine |
| |
Authors: | Nikolaos?C?Megoulas Email author" target="_blank">Michael?A?KoupparisEmail author |
| |
Institution: | (1) Laboratory of Analytical Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis, Athens 15771, Greece |
| |
Abstract: | A novel method for the direct determination of the aminoglycoside tobramycin was developed and validated based on reversed-phase high-performance liquid chromatography (RP-HPLC) with evaporative light scattering detector (ELSD). Using a Waters ODS-2 C18 Spherisorb column with an evaporation temperature of 45°C and nitrogen pressure of 3.5 bar, the selected mobile phase consisted of water/acetonitrile 55:45 containing 1.5 mL L–1 HFBA (11.6 mM) in an isocratic mode at a rate of 1.0 mL min–1. Tobramycins retention time was 4.3 min with an asymmetry factor of 1.7. A logarithmic calibration curve was obtained from 1 to 38 g mL–1 (r > 0.9998). LOD was 0.3 g mL–1; within-day %RSD was 1.0 (n
= 3, 4.7 g mL–1) and between-day %RSD was 1.1 (3 days within a week). The developed method was applied to the determination of tobramycin in a pharmaceutical crude substance and formulations (eye drops and ointments). Dilution experiments revealed the absence of interference from excipients (no constant and proportional errors); recovery from spiked samples was 99–103% with %RSD < 2.2 (n = 3×3). The developed HPLC/ELSD method was also found to be applicable in the determination of tobramycin in human plasma (0.6–12.5 g mL–1) and urine (1.5–12.5 g mL–1) after solid-phase extraction using carboxylate cartridges followed by solvent evaporation (×2 preconcentration). A mean recovery of 86% for plasma and 91% for urine was obtained. |
| |
Keywords: | Evaporative light scattering ELSD Tobramycin HPLC Aminoglycosides Pharmaceuticals Plasma Urine |
本文献已被 PubMed SpringerLink 等数据库收录! |