2,3-聚季铵盐附聚型离子色谱固定相的制备及其在SO42-分析中的应用

以四甲基乙二胺和1,3-二溴丙烷为原料,合成了聚电解质阳离子功能基--2,3-聚季铵盐功能基。以聚苯乙烯为种子,通过种子溶胀法制备了多孔型聚(苯乙烯-二乙烯基苯)微球(PS-DVB),并对其进行磺化。以附聚的方式在磺化的PS-DVB微球上附聚2,3-聚季铵盐功能基,得到附聚型离子交换固定相,通过匀浆法装入色谱柱,并将其用于SO₄^2-的分离分析。SO₄^2-能与其他常见的6种阴离子在8 min内完成分离,实现SO₄^2-的快速测定。其中,SO₄^2-的线性范围为0.5~50 mg/L,线性相关系数r为0.9992;加标回收率在99.2%~101.8%之间;峰面积和保留时间的相对标准偏差分别为2.4%和3.1%;根据信噪比(S/N=3)计算出检出限为0.04 mg/L。结果表明该自制色谱柱适用于复杂基质中SO₄^2-的快速测定。

Preparation of an agglomerated ion chromatographic stationary phase with 2,3-ionene and its application in SO42- analysis

The poly-electrolyte cation functional group of 2,3-ionene was synthesized with tetramethyl ethylenediamine and 1,3-dibromopropane as the raw materials. Multiporous polystyrene-divinylbenzene microsphere particles (PS-DVB) were produced by swelling method with polystyrene as seeds and sulfonated. Then the 2,3-ionene was bonded on the sulfonated multiporous polystyrene-divinylbenzene microsphere particles by agglomeration to get the agglomerative ion-exchange stationary phase. After optimizing the synthetic conditions, the new stationary phase was characterized by the techniques including scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and elemental analysis. The chromatographic column was packed by slurry method and applied in the analysis of SO₄^2- with a conductivity detector. SO₄^2- and other six common anions including F^-, Cl^-, NO₂^-, Br^-, NO₃^-, PO₄^3-, were separated and analyzed rapidly on the self-regulating chromatographic column within 8 min. The linear range was from 0.5 to 50 mg/L with correlation coefficient (r) of 0.9992. The LOD was 0.04 mg/L with S/N of 3. The relative standard deviations (RSDs, n=6) were 2.4% and 3.1% for the peak area and retention time, respectively. The recoveries were between 99.2% and 101.8%. The retention times of SO₄^2- did not change significantly after long time use of the self-regulating chromatographic column. The self-regulating chromatographic column is suitable for the detection of SO₄^2- in complex matrix samples.