摘要
针对传统检测方法在复杂基质中分离效率不足的问题,首次将响应面法(RSM)与高效液相色谱-电感耦合等离子体质谱(HPLC-ICP-MS)联用技术结合,建立了一种高灵敏度环境地表水中砷酸盐(As(Ⅴ))、亚砷酸盐(As(Ⅲ))、一甲基砷(MMA)、二甲基砷(DMA)、砷甜菜碱(AsB)、砷胆碱(AsC)6种形态砷的分析方法。通过Box-Behnken设计优化流动相pH(6.0~7.0)、甲醇比例(10%~20%)及进样量(20~40μL),成功的构建了二次回归模型(R^(2)_(Adj)=0.951),利用响应面法优化得出最优条件,研究发现pH与甲醇交互作用显著影响分离效率,最优条件为pH 6.7、甲醇13%、进样量28μL,总分离度达11.4±0.3。采用Hamilton PRP-X100色谱柱与梯度洗脱程序,6种形态砷(As(Ⅲ)、As(Ⅴ)、MMA、DMA、AsB、AsC)均能在12 min内实现基线分离(分离度>1.5),各形态砷检出限为0.06~0.17μg/L,加标回收率为95.4%~104.7%,相对标准偏差<6%。运用于实际水样分析显示,无机砷As(Ⅲ)和As(Ⅴ)占到总砷的60%~80%,是水中砷的主要存在形态。通过碰撞反应池技术能够有效消除^(40)Ar^(35)Cl^(+)干扰,建立的校正方程(I_(校正)=I_(实测)-0.13 I_(干扰))显著提升检测准确性。
To address the insufficient separation efficiency of traditional detection methods in complex matrices,a novel method was developed by integration response surface methodology(RSM)with high-performance liquid chromatography-inductively coupled plasma mass spectrometry(HPLC-ICP-MS)for the sensitive determination of six arsenic species in environmental surface water:arsenate(As(Ⅴ)),arsenite(As(Ⅲ)),monomethylarsonic acid(MMA),dimethylarsinic acid(DMA),arsenobetaine(AsB),and arsenocholine(AsC).A Box-Behnken design was employed to optimize the mobile phase pH(6.0~7.0),methanol ratio(10%~20%),and injection volume(20~40μL),resulting in a well-fitted quadratic regression model(R^(2)_(Adj)=0.951).Significant interaction between pH and methanol was observed.The optimal conditions were determined to be pH 6.7,13%methanol and 28μL injection,yielding a total resolution of(11.4±0.3).Using a Hamilton PRP-X100 column with gradient elution,all six arsenic species were baseline separated(resolution>1.5)within 12 minutes.Detection limits ranged from 0.06 to 0.17μg/L,with spike recoveries of 95.4%to 104.7%and relative standard deviations below 6%.Field analysis revealed inorganic arsenic species(As(Ⅲ)+As(Ⅴ))accounted for 60%~80%of total arsenic.Interference from ^(40)Ar^(35)Cl^(+) was effectively eliminated using collision/reaction cell technology(He flow 4.5 mL/min),and a correction equation(I_(corrected)=I_(measured)-0.13 I_(interference))significantly enhanced detection accuracy.
作者
牛倩
张军伟
NIU Qian;ZHANG Jun-wei(Luoyang Ecological&Environmental Monitoring Center,Luoyang 471000,China)
出处
《化学试剂》
2025年第8期59-65,共7页
Chemical Reagents
关键词
高效液相色谱-电感耦合等离子体质谱
形态砷
环境地表水
方法验证
无机砷
响应面法
high performance liquid chromatography-inductively coupled plasma mass spectrometry
arsenic species
environmental surface water
method validation
inorganic arsenic
response surface methodology
