Simultaneous analysis of antibiotics in biological samples by ultra high performance liquid chromatography–tandem mass spectrometry

Rapid and Simultaneous Quantitation of Amoxicillin and Clavulanic Acid in Human Plasma and Urine by Ultra-Performance Liquid Chromatography Tandem Mass Spectrometry and Its Application to a Pharmacokinetic Study

“…3 Representative chromatograms of amoxicillin (I), clavulanic acid (III), internal standard 2 (IS2, II) and IS3 (IV) obtained from (a) blank human urine, (b) blank human urine spiked with 0.0500 μg/mL of amoxicillin, 0.0500 μg/mL of clavulanic acid, 10.0 μg/mL of IS2 and 1.00 μg/mL of IS3, (c) a volunteer urine sample at 8 -12 h after intravenous administration of a single dose of 0.5/0.05 g amoxicillin sodium and clavulanate potassium (10:1) (measured concentration was 2.41 μg/mL for amoxicillin and 0.0890 μg/mL for clavulanic acid). acid) 18,24 had much lower sensitivity than in our method. The LLOQ of amoxicillin and clavulanic acid, reported by Carlier et al, was 0.5 μg/mL in plasma.…”

“…24 In Cazorla-Reyes's method, it was 0.2 μg/mL for serum samples and 0.5 μg/mL for urine samples. 18 So the reported methods may not be appropriate for our study.…”

“…17 In addition, no LC-MS/MS method was reported for the simultaneous determination of amoxicillin and clavulanic acid in urine samples. Also, there are other problems such as high matrix effect in urine samples, 18 poor stability of clavulanic acid at room temperature and after freeze-thaw circle, 19,20 poor stability of clavulanic acid in long-term stability tests. 21 Therefore, it is necessary to develop sensitive, reliable methods to simultaneously determine amoxicillin and clavulanic acid in both plasma and urine samples to assess pharmacokinetics characteristics of combination of two compounds at a ratio of 10:1 in humans.…”

An Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry Method for the Quantification of Vancomycin Requiring Only 2 µL of Rabbit Serum

“…There are several methodologies available for the measurements of VAN in biological matrices that include radioimmunoassays, fluorescence immunoassays, fluorescence polarization immunoassays [3], particle enhanced turbidimetric inhibition immunoassays (PETINIA) [4], liquid chromatography (LC) [5], and LC-tandem mass spectrometry (LC-MS/MS) [6] [7] [8] [9]. These methods were successfully used to measure VAN in a variety of matrices, but they had their limitations.…”

“…These methods were successfully used to measure VAN in a variety of matrices, but they had their limitations. They either were not sufficiently precise [3], suffered from interference [4], had insufficient sensitivity [5] [6] [8], or required large sample volumes [6] [8] [7] [9]. Large sample volumes are sometimes difficult to obtain, especially in studies where VAN is determined in the samples of small laboratory animals, such as rabbits, where the availability of the biological matrix is limited.…”