胶束电动毛细管色谱法测定大气中的甲醛、乙醛和丙酮

Determination of Formaldehyde, Acetaldehyde and Acetone in the Atmosphere by Micellar Electrokinetic Capillary Chromatography

用胶束电动毛细管色谱法同时测定了大气污染物甲醛、乙醛和丙酮。样品经２，４－二硝基苯肼衍生。采用４７ｃｍ（到检测窗口４０ｃｍ）×５０μｍｉ．ｄ．毛细管柱，以５０ｍｍｏｌ／Ｌ十二烷基硫酸钠－２０ｍｍｏｌ／Ｌ四硼酸钠溶液（ｐＨ９．００）为操作缓冲溶液，电压３０ｋＶ，检测波长２１４ｎｍ，７．５ｍｉｎ内甲醛、乙醛和丙酮的２，４－二硝基苯腙衍生物可获得良好的分离。用峰面积定量，线性范围为０．０１～０．５ｇ／Ｌ，最小检出浓度均为２ｍｇ／Ｌ，变异系数在８．７％以内。

A micellar electrokinetic capillary chromatographic method was developed for quantitative determination of environmental pollutants, formaldehyde, acetaldehyde and acetone in the atmosphere. The samples were derivatized to 2,4 dinitrophenylhydrazones. A fused silica capillary of 47cm×50μm i.d. (40cm to detector) was used. Running buffer was 20mmol/L aqueous tetraborate solution containing 50mmol/L sodium dodecyl sulfate (pH 900). The voltage used was 30kV. Detection wavelength was 214nm. The 2,4 dinitrophenylhydrazones were separated well within 75min. Peak area was used for quantitative analysis. The calibration curves were linear over 001 05g/L. The minimum detectable concentrations were 2mg/L. The variations were within 87%. The detection sensitivity of this method can be further improved through utilizing a filter of 350nm and a larger detection window. This method can also be applied to the determination of formaldehyde, acetaldehyde and acetone in other environmental samples.