摘要
建立了离子印迹壳聚糖/凹凸棒石(IICA)分离富集-火焰原子吸收光谱(FAAS)测定中药材中痕量Cd(Ⅱ)的新方法。在动态吸附条件下,系统研究了溶液pH值、流速、洗脱条件和干扰离子对痕量Cd(Ⅱ)分离富集的影响。研究表明,在pH为4.5,上样流速为0.60mL/min条件下,Cd(Ⅱ)能被IICA定量富集;吸附的Cd(Ⅱ)可用1.0mol/L HCl-0.1mol/L甲基异丁酮的乙醇溶液,在流速为0.96mL/min条件下完全洗脱。优化条件下,IICA对Cd(Ⅱ)的动态吸附容量为56.45mg/g。线性范围为0.00097～1.28mg/L,r=0.9994,检出限(3σ,n=11)为0.97μg/L,相对标准偏差为1.32%(n=6,c=0.08mg/L),回收率在96.5%～106.4%之间。该方法操作简便,灵敏度和精密度高,可应用于实际中药材样品中痕量镉的测定。
A method for the determination of trace Cd（Ⅱ）in traditional chinese medicine by FAAS after separation and preconcentration with Cd（Ⅱ）ions imprinted chitosan/attapulgite（IICA）has been established.Under the dynamic adsorption conditions,the optimal pH of the solution,flow rate,elution conditions were obtained for preconcentration of trace Cd（Ⅱ）,and the effect of interfering ions was also investigated.It was found that Cd（Ⅱ）could be quantitatively preconcentrated on IICA at pH=4.5.The flow rates of sample solutions and eluting solution with 1.0 mol/L HCl-0.1 mol/L methyl isobutyl ketone alcohol were 0.60mL/min and 0.96mL/min,respectively.The dynamic adsorption capacity of Cd（Ⅱ）on IICA was 56.45 mg/g.The linear range for Cd（Ⅱ）was 0.00097～1.28 mg/L,with a correlation coefficient of 0.9994.The detection limit for Cd（Ⅱ）was 0.97μg/L（3σ,n=11）.The relative standard deviation was 1.32%（n=6,c=0.08mg/L）,and the recovery was in the range of 96.5%～ 106.4%.The method is convenient,highly precise and linear in a wide range and has been applied to the determination of trace amount Cd（Ⅱ）in water samples with satisfactory results.
出处
《分析科学学报》
CAS
CSCD
北大核心
2012年第3期348-352,共5页
Journal of Analytical Science
基金
江苏省自然科学基金(No.BK2008196)
淮安市工业支撑项目(No.HAG2011011)
关键词
离子印迹技术
凹凸棒石黏土
壳聚糖
分离富集
火焰原子吸收光谱
Cd(Ⅱ)
Ions imprinting technique
Attapulgite
Chitosan
Separation and preconcentration
Flame atomic absorption spectrometry
Cd（Ⅱ）
