离子抑制色谱法测定消毒剂中的过氧乙酸和过氧化氢

Determination of Peroxyacetic Acid and Hydrogen Peroxide by Ion Suppression Chromatography in Disinfectants

采用离子抑制色谱法,用反相C18色谱柱,在不经过衍生的情况下,同时测定了过氧乙酸消毒剂中过氧乙酸(PAA)和过氧化氢(H2O2)的含量。该法以酸性磷酸盐为缓冲液,抑制PAA和乙酸的离解,增大了其保留因子,使组分间能得到很好的分离。利用磷酸盐缓冲溶液在210nm以下的紫外吸收强度比水低的特性,降低了基线噪声,提高了过氧化物测定的灵敏度。组分的检出限分别为3 0×10-7mol/L(PAA)和6 2×10-8mol/L(H2O2)(进样量100μL,相当于检出限为2 3ng(PAA)和2 1ng(H2O2))。

Peroxyacetic acid (PAA) and hydrogen peroxide (H2O2) in disinfectants were determined simultaneously without derivatization by ion suppression chromatography. A Hypersil ODS column (250 mm×40 mm id, 5 μm) was used with 15 mmol/L phosphate buffer solution (PBS) (pH 22)acetonitrile (82∶18, v/v) as mobile phase. The flow rate was 08 mL/min, and the detection wavelength was 205 nm. In this method, PBS was used to control the dissociation of PAA and HAc,and to increase the retention factors. The baseline noise was reduced as PBS having lower absorption at 200-210 nm than water, and consequently the sensitivity was improved. The limits of detections of PAA and H2O2 were 23 ng and 21 ng, corresponding to PAA and H2O2 concentrations of 30×10-7 mol/L and 62×10-8 mol/L respecively when the injecting volume was 100 μL. The relative standard deviations were less than 05%. The analysis time was within 5 min.