High performance liquid chromatographic determination of clavulanic acid in human urine.

Abstract

An ion pair reversed phase HPLC method for the determination of clavulanic acid has been developed. Since clavulanic acid had poor absorption O,mas 201 nm in water) in a UVregion suitable for HPLC detection, the detectability was enhanced by bathochromic shift of )maa due to solvent effect. The shifts of 2ma.., were measured with the solutions containing clavulanic acid, tetrabutylammonium bromide, and phosphate buffer salts in aqueous methanol. The magnitudes of the observed shifts were investigated with respect to pH, ionic strength, methanol content, and TBAB concentration.The results indicated that TBAB concentration was the predominant factor responsible for the bathochromic shifts. Taking account of the results together with solvent effects on the retention of clavulanic acid on hydrophobic stationary phase, HPLC condition suitable for detection and separation of clavulanic acid in urine was established as follows; mobile phase: 10 mm TBAB+0.6 mm NaH2PO4 +0.4 mat Na2HPO4 in H2O-MeOH, 10: 1 (v/v) (pH 7.02), flow rate: 1.5 ml/minute, stationary phase: LiChrosorb RP-18 (25 cm x 4.6 mm i.d.), detection: UV 220 run. The applicability of the present method is demonstrated by determining the time course of urinary excretion of clavulanic acid after oral administration of a conjugated tablet of clavulanic acid and amoxicillin to human subject. found that the conjugated dose of clavulanic acid and amoxicillin was able to clean the turbid urine of patients with amoxicillin-resistant urinary tract infections, and HEEREMA et al.11> reported a similar observation with respect to the mice with renal infections. Some information also has been published on the chemical properties of clavulanic acid; the available papers described the chemical") and kinetic" investigations of the inactivation of (3-lactamase and biosynthesis of clavulanic acid.",")The assay method so far employed in the previous works has been limited to microbiological methods. None referred to chemical and spectrometric procedures for the assays of clavulanic acid, possibly because clavulanic acid has no appreciable absorption in a UV region above 210 nm,16> and neither iodometric nor hydroxamate assays are suitable for quantitative purposes.',)The present work attempts to investigate solvent effects on shifts of clavulanic acid solutions, to find a solvent system appropriate to UV detection and separation by a reversed phase HPLC, and to demonstrate the applicability of the established method to the determination of clavulanic acid excreted in human urine.

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

“…14,16,22 While a matrix effect was observed, 16,22 or not reported 17 in literatures using the above methods. HLB extraction SPE method with high sensitivity and reproducibility but low matrix effect was used in this study.…”

“…13 The concentrations of antibiotics should be comparable to minimal inhibition concentration (MIC) in the blood, urine and infection site during the treatment. 14,15 Furthermore, a pharmacokinetic/pharmacodynamic (PK/PD) study indicated that the amoxicillin and clavulanic acid combination for Streptococcus pneumoniae, Haemophilus influenzae was effective when the percentage time above the minimal inhibition concentration (%T>MIC) of the plasma concentration was over 35 -40%. 9,10 So it is important to develop a sensitive and reliable detection method to assess drug pharmacokinetics in human, and then to find an appropriate dose regimen in the clinical.…”

Assay of amoxicillin and clavulanic acid, the components of Augmentin, in biological fluids with high-performance liquid chromatography

“…With urine samples which contain slower-running components, the assay time is somewhat longer. The assay of clavulanic acid in urine by using HPLC has been previously described by Haginaka et al (6). This ion pair HPLC method had a detection limit of 5 ,ug/ml for clavulanic acid and was not suitable for the assay of clavulanate in serum.…”

Beta-Lactamase Inhibitors: Another Approach to Overcoming Antimicrobial Resistance

“…6 t)nly 20% to 60% appears unchanged in urine 6 hours |ifter an oral dose in humans. 14 A single oral dose of 125 mg clavulanic acid yielded values of 115 to 508 in the first 2 hours, 150 to 439 at 2 to 4 hours, and 45 to 74 at 4 to 6 hours. 5 -6 -815 - 16 Studies have shown the clearance of clavulanic acid may depend on renal function with accumulation occurring when creatinine clearance falls below 10 ml/min.…”