Department of Physical Chemistry, School of Chemistry and Molecular Engineering, East China University of Science and Technology, Meilong Road 130, Shanghai 200237, PR China.
Talanta. 2012 May 30;94:257-62. doi: 10.1016/j.talanta.2012.03.036. Epub 2012 Mar 29.
A near-infrared-emitting CdTe/CdS core/shell quantum dots (QDs)-based photoluminescence (PL) sensor was designed and applied for highly selective and sensitive detection of Cd(2+). This sensor was based on a PL "OFF-ON" mode. First, the addition of ammonium pyrrolidine dithiocarbamate (APDC) led to remarked PL quenching of QDs. Second, PL of APDC surface modified QDs (QDs-APDC) was gradually restored with the each increment of Cd(2+) concentration. Experimental results showed that PL of QDs-APDC was near proportional upon the addition of Cd(2+) in the range from 0.1 to 2 μM with a good correlation coefficient of 0.9989. The limit of detection of this proposed method was 6 nM. Interferential experiments confirmed that this sensor of Cd(2+) was highly selective over other metal ions. To further investigate perfect analysis performance, this sensor was favorably utilized to determine Cd(2+) in tap water, river water and liposome solutions.
一种基于近红外发射的 CdTe/CdS 核/壳量子点（QD）的光致发光（PL）传感器被设计并应用于高选择性和高灵敏度的 Cd(2+)检测。该传感器基于 PL“关-开”模式。首先，加入氨乙基二硫代甲酸钠（APDC）会导致 QD 的 PL 显著猝灭。其次，随着 Cd(2+)浓度的逐个增加，APDC 表面修饰的 QD（QD-APDC）的 PL 逐渐恢复。实验结果表明，在 0.1 至 2 μM 的 Cd(2+)范围内，QD-APDC 的 PL 近乎呈正比例增加，相关系数为 0.9989。该方法的检出限为 6 nM。干扰实验证实，该 Cd(2+)传感器对其他金属离子具有高度选择性。为了进一步研究完美的分析性能，该传感器被有利地用于测定自来水中、河水中和脂质体溶液中的 Cd(2+)。
