A fluorescent biosensor of lysozyme-stabilized copper nanoclusters for the selective detection of glucose. Issue 123 (25th November 2015)

• Record Type: Journal Article
• Authors: Wang, Chan; Shu, Shili; Yao, Yagang; Song, Qijun
• Is Part Of: RSC advances. Volume 5:Issue 123(2015)
• Page Start: 101599
• Page End: 101606
• Publication Date: 2015-11-25
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c5ra19421k
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Fluorescent copper nanoclusters (Lys-CuNCs) were synthesized using lysozyme as a template, displaying smart response to glucose concentration with high sensitivity. The visualization variation of Lys-CuNCs may further enable the rapid and simple detection of blood glucose. Abstract : Glucose biosensors have attracted increased attention, as the rapid and sensitive detection of glucose is highly desirable for diabetes diagnosis. In this article, we designed a type of lysozyme functionalized fluorescence copper nanoclusters (Lys-CuNCs) to detect glucose levels in blood samples. Fluorescence measurements were carried out to optimize the synthesis conditions ( e.g. mass ratio, pH and reaction time) for the biosensor. Under optimum conditions, the obtained Lys-CuNCs with an average diameter of 2 nm exhibited bright orangey-red fluorescence with high quantum yields (up to 5.6%). The fluorescence signal of Lys-CuNCs was quenched upon the addition of glucose, presumably due to the reduction of Cu(i ) on the NCs surface by glucose. Thus the Lys-CuNCs can be served as a biosensor for glucose detection and two linear response ranges respectively in 0.03–10 μM and 0.5–10 mM of glucose were observed with a detection limit of 1.9 nM. Furthermore, this biosensor showed superior selectivity for various interferences, including light radiation, metal ions, carbohydrates and amino acids. In view of these properties, the Lys-CuNCs biosensor was applied in the determination of glucose in blood samples, and the results agreed well with that obtained from a currently used clinical method. Finally the visualized fluorescence variation of Lys-CuNCs may further enable the rapid and simple detection of glucose level in blood.