离子色谱自动进样器塑料小瓶残留离子的检测

Determination and Comparison of Ion Residues in Different Autosampler Plastic Vials by Ion Chromatography

目的了解离子色谱公司商品化的自动进样器小瓶阴、阳离子残留状况及浸泡时间对离子释放程度的影响。方法阳离子采用IonPacCS12A阳离子色谱交换柱,甲烷磺酸等度淋洗,抑制型电导检测;阴离子采用IonPacAS15阴离子交换柱,氢氧化钠等度淋洗,抑制型电导检测。将4种商品化的小瓶用一定体积的去离子水浸泡不同时间后直接进样分析,检测了低至μg/L级(以溶液计)的残留离子。结果该方法对Cl-、NO2-、NO3-、SO42-、Na+、K+、Mg2+、Ca2+的检出限(S/N=3)为0.79～5.28μg/L,线性范围为1～20000μg/L,线性相关系数为0.9983～0.9999,连续7次进样RSD值均小于3%,加标回收率在83.3%～112%之间。结论该方法能够满足实际检测工作要求,并提出了适宜的修复建议,可以进行推广。

Objective The present paper compared the ion residues including cations residues and anions residues in autosampler plastic vials from 4 different ion chromatography companies and discussed the relationship between soaking duration time and ion releasing. Methods The separation and determination were carried out by IonPac CS12A cation exchange column, MSA isocratic eluent together with suppressed conductivity detector; and IonPac AS15 anion exchange column, NaOH isocratic eluent together with suppressed conductivity detector. 4 plastic vials from 4 companies were soaked in DI water with a particular volume followed by injecting the liquid samples to IC system in order to measure residue ions with low level（μg/L）. Results The detection limits were 0.79-5.28 μg/L.The linear range were 1-20 000 μg/L for Cl^-, NO2^-, NO3^-, SO4^2-, Na^＋, K^＋, Mg^2＋, Ca^2＋. The linear coefficients were 0.998 3-0.999 9. RSDs were below 3%.The recovery rates were 83.3%-112%. Conclusion This method satisfies the requirement of practical examination, and the suitable methods for repairing the plastic vials of autosampler is proposed.