Ziółczyk Paulina, Kur-Kowalska Katarzyna, Przybyt Małgorzata, Miller Ewa
Institute of General Food Chemistry, Lodz University of Technology, Stefanowskiego 4/10, 90-924 Łódź, Poland.
Institute of General Food Chemistry, Lodz University of Technology, Stefanowskiego 4/10, 90-924 Łódź, Poland.
Spectrochim Acta A Mol Biomol Spectrosc. 2014 May 21;126:28-35. doi: 10.1016/j.saa.2014.01.112. Epub 2014 Feb 7.
Results of studies on optical properties of low toxicity quantum dots (QDs) obtained from copper doped zinc sulfate are discussed in the paper. The effect of copper admixture concentration and solution pH on the fluorescence emission intensity of QDs was investigated. Quenching of QDs fluorescence by oxygen was reported and removal of the oxygen from the environment by two methods was described. In the chemical method oxygen was eliminated by adding sodium sulfite, in the other method oxygen was removed from the solution using nitrogen gas. For elimination of oxygen by purging the solution with nitrogen the increase of fluorescence intensity with decreasing oxygen concentration obeyed Stern-Volmer equation indicating quenching. For the chemical method Stern-Volmer equation was not fulfilled. The fluorescence decays lifetimes were determined and the increase of mean lifetimes at the absence of oxygen support hypothesis that QDs fluorescence is quenched by oxygen.
本文讨论了从掺杂铜的硫酸锌中获得的低毒性量子点（QDs）光学性质的研究结果。研究了铜掺杂浓度和溶液pH值对量子点荧光发射强度的影响。报道了氧气对量子点荧光的猝灭作用，并描述了通过两种方法从环境中去除氧气的过程。在化学方法中，通过添加亚硫酸钠去除氧气，在另一种方法中，使用氮气从溶液中去除氧气。对于用氮气吹扫溶液去除氧气的情况，荧光强度随氧气浓度降低而增加，符合Stern-Volmer方程，表明发生了猝灭。对于化学方法，Stern-Volmer方程不成立。测定了荧光衰减寿命，在无氧条件下平均寿命的增加支持了量子点荧光被氧气猝灭的假设。
