毛细管电泳间接紫外检测花粉中的金属阳离子

Determination of metal cations in pollen by capillary electrophoresis with indirect UV detection

用毛细管电泳间接紫外法在4min内快速测定了花粉中4种金属阳离子（K^＋，Na^＋，Ca^2＋，Mg^2＋）．以4mmol／LCuSO4为背景吸收物质，4mmol／LHAc为络合剂，0．1mol／L硫酸调节pH=3．40，温度25℃，运行电压20kV，紫外检测波长214nm的优化条件下，4种金属阳离子均达到基线分离，检测限0．1～0．5mg／L，迁移时间和峰面积的相对标准偏差（RSD）分别小于0．62％和6．3％（n=5）．结果表明，该方法线性范围宽，选择性好，实际花粉样品测定结果与原子吸收法一致．

Determination of K^＋ ,Na^＋ ,Ca^2＋ and Mg^2＋ can be achieved within 4 min in pollen samples by capillary electrophoresis with indirect UV detection. An electrolyte system contained 4 mmol/L copper sulfate and 4 mmol/L acetic acid is used, and pH is maintained to 3.40 using 0. 1 mol/L H2SO4. The running voltage is 20 kV at 25 ℃. Under the optimum conditions, four cations are completely separated. The detection limits（S/N=3） are down to 0.1 through 0. 5 mg/L. The relative standard derivations of the migration times and peak areas are less than 0.62 and 6.3% （n = 5）, respectively. The proposed method with a wide linear range and satisfactory accuracy has successfully been used to measure contents of the four metal ions in several pollen samples and it is found that the results are consistent with those of AAS.