三聚磷酸钠稳定硫化镉量子点荧光猝灭法测定痕量铁  

Sodium Tripolyphosphate-Stabilized CdS QDs of Trace Iron by Fluorescence Quenching Method

作　　者：杨传孝[1] 孙向英[1] 

机构地区：[1]华侨大学材料科学与工程学院,福建泉州362021

出　　处：《华侨大学学报（自然科学版）》2011年第5期537-542,共6页Journal of Huaqiao University(Natural Science)

基　　金：国家自然科学基金资助项目(20955001);国务院侨务科研基金资助项目(09QZR05);福建省自然科学基金资助项目(D0810016);华侨大学科研基金资助项目(JB-ZR1118)

摘　　要：以三聚磷酸钠(STPP)为稳定剂,硫脲为硫源,在碱性介质中成功合成分散较均匀、水溶性好、半峰宽为25 nm左右的CdS量子点(QDs).研究三聚磷酸钠和硫脲的用量、反应时间及pH值等条件对CdS QDs发射光谱特性的影响.以该纳米粒子作为离子探针,建立测定痕量Fe2+的荧光猝灭方法.结果表明:在0.02～1.20μmol.L-1范围内,Fe2+对STPP-CdS QDs荧光猝灭符合Stern-Volmer方程,483 nm处F0/F与Fe2+呈现良好的线性关系,检测限为6.7 nmol.L-1;对于实际矿泉水样中Fe的测定,其相对标准偏差为2.2%～3.8%,回收率为95.0%～105.0%.The uniform dispersion and water-soluble CdS quantum dots （QDs） stabilized by sodium tripolyphosphate （STPP） were successfully synthesized in an alkaline medium, where the S2 was obtained from thiourea. The half peak width of CdS QDs was about 25 nm. The fluorescence spectral properties of CdS QDs with varying adding amount of STPP and thiourea, pH values, and reaction time were investigated. By the STPP-CdS QDs as ion probe, a new fluores cenee quenching method for the determination of trace iron （ II ） was developed. The fluorescence quenching results followed the Stern-Volmer equation, and the values of F0/F at 483 nm is linearly proportional to the concentration of Fe2＋ from 0. 02-1.20 μmol - L-1. The detection limit of the developed method was 6. 7 nmol · L-1 for Fe2＋. Mineral water samples were analyzed with the relative standard deviation （RSD） of 2. 2~3.8% and the recovery of 95. 0%105. 0%.

关 键 词：三聚磷酸钠 CDS量子点 亚铁离子 荧光猝灭 

分 类 号：O657.31[理学—分析化学]