He Yu, Wang He-Fang, Yan Xiu-Ping
Research Center for Analytical Sciences, College of Chemistry, Nankai University, 94 Weijin Road, Tianjin 300071, China.
Anal Chem. 2008 May 15;80(10):3832-7. doi: 10.1021/ac800100y. Epub 2008 Apr 12.
While most research works focus on the development of quantum dots (QDs)-based fluorescence sensors, much less attention is paid to the phosphorescence properties of QDs and their potential for phosphorescence detection. In this work, the phosphorescence property of Mn-doped ZnS QDs is explored to develop a novel room-temperature phosphorescence (RTP) method for the facile, rapid, cost-effective, sensitive, and selective detection of enoxacin in biological fluids. The Mn-doped ZnS QDs-based RTP method reported here does not need the use of deoxidants and other inducers and allows the detection of enoxacin in biological fluids without interference from autofluorescence and the scattering light of the matrix. The Mn-doped ZnS QDs offer excellent selectivity for detecting enoxacin in the presence of the main relevant metal ions in biological fluids, biomolecules, and other kinds of antibiotics. Quenching of the phosphorescence emission due to the addition of enoxacin at 1.0 microM is unaffected by 5000-fold excesses of Na (+) and 10000-fold excesses of K (+), Mg (2+), and Ca (2+). Amino acids such as tryptophan, histidine, and l-cysteine at 1000-fold concentration of enoxacin do not affect the detection of enoxacin. Glucose does not affect the detection at 10000-fold concentration of enoxacin. Typical coadministers (mainly other types of antibiotics) such as ceftezole, cefoperazone, oxacillin, and kalii dehydrographolidi succinas are permitted at 50-, 10-, 100-, and 50-fold excesses, respectively, without interference with the detection of enoxacin. The precision for 11 replicate detections of 0.4 microM enoxacin is 1.8% (RSD). The detection limit for enoxacin is 58.6 nM. The recovery of spiked enoxacin in human urine and serum samples ranges from 94 to 104%. The developed Mn-doped ZnS QDs-based RTP method is employed to monitor the time-dependent concentration of enoxacin in urine from a healthy volunteer after the oral medication of enoxacin. The investigation provides evidence that doped QDs are promising for RTP detection in further applications.
虽然大多数研究工作都集中在基于量子点（QD）的荧光传感器的开发上，但对量子点的磷光特性及其磷光检测潜力的关注却少得多。在这项工作中，研究了Mn掺杂ZnS量子点的磷光特性，以开发一种新颖的室温磷光（RTP）方法，用于简便、快速、经济高效、灵敏且选择性地检测生物流体中的依诺沙星。本文报道的基于Mn掺杂ZnS量子点的RTP方法无需使用脱氧剂和其他诱导剂，并且能够在不受到自发荧光和基质散射光干扰的情况下检测生物流体中的依诺沙星。Mn掺杂ZnS量子点在生物流体中的主要相关金属离子、生物分子和其他种类抗生素存在的情况下，对检测依诺沙星具有出色的选择性。在添加1.0 microM依诺沙星时，磷光发射的猝灭不受5000倍过量的Na(+)和10000倍过量的K(+)、Mg(2+)和Ca(2+)的影响。依诺沙星浓度1000倍的色氨酸、组氨酸和L-半胱氨酸等氨基酸不会影响依诺沙星的检测。葡萄糖在依诺沙星浓度10000倍时不影响检测。典型的共同给药药物（主要是其他类型的抗生素）如头孢唑林、头孢哌酮、苯唑西林和穿琥宁分别在50倍、10倍、100倍和50倍过量时允许存在，而不会干扰依诺沙星的检测。对0.4 microM依诺沙星进行11次重复检测的精密度为1.8%（相对标准偏差）。依诺沙星的检测限为58.6 nM。加标依诺沙星在人尿和血清样品中的回收率为94%至104%。所开发的基于Mn掺杂ZnS量子点的RTP方法用于监测健康志愿者口服依诺沙星后尿液中依诺沙星随时间变化的浓度。该研究提供了证据表明掺杂量子点在进一步应用中用于RTP检测具有前景。
