Determination of hydrochlorothiazide in water by solid phase extraction-high performance liquid chromatography

Abstract

In order to accurately determine the trace content of hydrochlorothiazide in water, a solid phase extraction (SPE) combined with high performance liquid chromatography (HPLC) was established. Firstly, the collected water sample (1 000 mL) was purified by activated HLB SPE column after filtration and pH adjustment. Then the HLB column was eluted with 10 mL of pure methanol, blown to nearly dry with nitrogen, and mixed with 1 mL methanol. Finally, the obtained solution was detected by HPLC. Detection conditions were as following: the chromatographic column was ZORBAX Eclipse Plus C18(4.6 mm×250 mm, 5 μm), the mobile phase was methanol/water (70∶30), the flow rate was 1 mL/min, the elution was carried out according to isocratic method, the detection wavelength was 270 nm, and the external standard method was used for quantification. The results show that when the mass concentration of hydrochlorothiazide is in the range of 0.1~50.0 μg/L, the concentration of the determinand is in direct proportion with the chromatographic peak area, and the linear equation is [WTBX]A=221.49c+3 915, while R2</sup>=0.999 7; The sample is stable within 24 h, with an average recovery rate of 99.90%(RSD=1.8%,[WTBX]n=5), and a precision is 1.1%. The method has the advantages of simple operation, high precision, low detection concentration, simple preparation of mobile phase and little environmental pollution. It can be used for the detection, analysis and risk assessment of trace hydrochlorothiazide in water environment.

Keywords

• chemical analysis; high performance liquid chromatography (hplc); hydrochlorothiazide; solid phase extraction (spe); water