Extraction and Determination of Vancomycin Antibiotic in Hospital Sewage Samples by Solid Phase Extraction-High Performance Liquid Chromatography

Vancomycin، as β-lactam classes of antibiotics، is widely used for treating infectious diseases in hospitals. Therefore، it is necessary to establish a method for precise measurement of vancomycin in hospital sewage as an emerging pollutant that causes bacterial resistance.

In this study، solid phase extraction was used for separation of vancomycin from hospital wastewater. Vancomycin recovery rate were investigated at pH 3 and 7. The extracted samples were passed through a C18 column at 20 °C using different ratios of mobile phase of acetate/acetonitrile buffer with flow rate of 0. 8 ml min-1. The quantity of vancomycin in samples was detected by high performance liquid chromatography (HPLC) equipped with UV detector at 240 nm wave length.

The best condition for extraction was achieved at pH=7 with a recovery of 89%. Better results were obtained by mobile phase of acetate/acetonitrile buffer with volume ratio of 89:11 at pH=4. The linearity coefficients (R2) of 0. 97 and 0. 96 were obtained for vancomycin concentration ranges of 1-45 and 50-120 µg l-1 at optimum condition، respectively. Limit of Detection (LOD) and Limit of Quantification (LOQ) were calculated as 3 and 10 µg l-1 respectively. Also، variations in precision of both hourly and daily measurements of standard solution were less than 10%.

The results of this study might be applied as a specific method for extraction and analysis of vancomycin antibiotic in hospital sewage samples.