巯基改性聚乙烯醇为结合相的薄膜扩散梯度技术  

Preparation of Thiol-Polyvinyl Alcohol and Its Application to Diffusive Gradients in Thin-Films Technique

作　　者：范洪涛[1] 孙挺[1] 薛明智[1] 仝桂锋[1] 隋殿鹏[1] 

机构地区：[1]东北大学化学系,沈阳110004

出　　处：《分析化学》2009年第9期1379-1381,共3页Chinese Journal of Analytical Chemistry

摘　　要：利用巯基乙酸改性了聚乙烯醇,制得了巯基聚乙烯醇(PVA-SH)。研究了以1.0mmol/LPVA-SH溶液为结合相的薄膜扩散梯度(DGT)装置(PVA-SHDGT)对Cd2+测量的有效性;考察了pH值、离子强度对PVA-SHDGT累积Cd2+的影响;测量了PVA-SHDGT对Cd2+的饱和累积容量。实验表明:巯基乙酸成功地接枝到PVA上,巯基含量为1.65%(wt%);PVA-SHDGT对Cd2+的饱和累积容量为0.234mol/L;当pH值在5.5～9.9范围内、离子强度在0.0001～0.7mol/L内基本不影响PVA-SHDGT对Cd2+的累积;PVA-SHDGT能够定量测定水中的Cd2+,回收率为100.7%,线性相关系数r=0.9812。结果表明:PVA-SH可以作为DGT技术新的液态结合相。A new functional thiol-polyvinyl alcohol（PVA-SH） that was applied to the diffusive gradients in thin-films（DGT） technique was prepared with thioglycolic acid to import-SH group into a polyvinyl alcohol（PVA） framework.The validation of DGT device（PVA-SH DGT） with 1.0 mmol/L PVA-SH solution as the liquid binding phase for Cd2＋ were studied in synthetic solution.The effects of pH and ionic strength on binding capacity of PVA-SH DGT were assessed.The experiments showed that the thiol groups had been imported into the chain of PVA and the content of sulfur of PVA-SH was 1.65%（wt%）.The saturated binding capacity of PVA-SH DGT for Cd2＋ was 0.234 mmol/L.The PVA-SH DGT had a substantial binding capacity at pH 5.5-9.9 and concentrations of competitive Na＋ from 0.0001 mol/L to 0.7 mol/L.The Cd2＋ concentration in synthetic solution was accurately determined by PVA-SH DGT（recovery=100.7%,r=0.9812）.The PVA-SH may be suitable as one of the liquid binding phase of DGT technique.

关 键 词：聚乙烯醇 巯基 薄膜扩散梯度 结合相 镉 

分 类 号：O652[理学—分析化学]