A fluorescent biosensor of lysozyme-stabilized copper nanoclusters for the selective detection of glucose

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.

Lysozyme coated copper nanoclusters for green fluorescence and their utility in cell imaging

“…Thus the lyz-CuNCs reported in this paper exhibited a shift of 60 nm in their fluorescence emission when compared to the blue lyz-CuNCs reported in the literature. 13 Thus, our green fluorescent lyz-CuNCs complement the blue 13 and red 14 nanoclusters reported in the literature by completing the range of emission of 450 to 600 nm via bridging the gap with its emission centered at 510 nm. As compared to other pH conditions studied, at pH = 7, the agglomeration is prevented due to the capping of lyz that results in exhibiting significant fluorescence emission intensity at 510 nm ( Fig.…”

“…In the case of blue fluorescent lyz-CuNCs, 2 to 9 copper bound nanoclusters (Cu 2 , Cu 4 and Cu 9 ) were reported, 13 while no MALDI studies were reported in the case of red lyz-CuNCs. 14 An FTIR spectrum of simple protein shows an amide peak at B1600 cm À1 along with a shoulder at B1700 cm À1 . In the case of lyz-CuNCs, only the shoulder disappears and the amide band is retained, suggesting the capping of CuNCs by the protein, lysozyme.…”

“…5 Recent studies showed that the fluorescent CuNPs are stabilized by proteins, such as BSA, which gives red fluorescence, and lysozyme, which gives both red and blue fluorescence. [12][13][14][15][16][17][18] Therefore, the stabilization of fluorescent nanoclusters of copper emitting in the visible region is still a challenging task. Proteins have been widely used in directing the synthesis of functional nanomaterials owing to the coordinating ability of -NH 2 , -COOH, -CONH-, -OH and -SH groups present as side chains in proteins.…”

In Situ Generation of Fluorescent Copper Nanoclusters Embedded in Monolithic Eggshell Membrane: Properties and Applications

“…Recently, many efforts have led to some approaches for Cu NCs syntheses such as polymer and biomolecule templated methods [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 ], electrochemical reduction [ 32 ], sonochemical synthesis [ 33 ], microwave-assisted [ 34 , 35 , 36 ] and microemulsion technology [ 37 , 38 ]. However, those as-prepared Cu NCs are mostly dispersed in homogeneous solution.…”

Luminescent Metal Nanoclusters for Potential Chemosensor Applications

“…In biomolecule detection, the lysozyme functionalized fluorescent copper nanoclusters (Lys-Cu NCs; Φ = 5.6%)-based glucose sensor viaa fluorescence quenching effect was reported by Wang et al [147]. Lys-Cu NCs displayed the two linear response ranges with glucose between 0.03-10 μM and 0.5-10 mM with an LOD of 1.9 nM.…”