title: Protein-directed synthesis of pH-responsive red fluorescent copper nanoclusters and their applications in cellular imaging and catalysis.
abstract: The development of functional copper nanoclusters (Cu NCs) is becoming increasingly widespread in consumer technologies due to their applications in cellular imaging and catalysis. Herein, we report a simple protein-directed synthesis of stable, water-soluble and fluorescent Cu NCs, using BSA as the stabilising agent. Meanwhile, in this study, hydrazine hydrate (N₂H₄·2H₂O) was used as the reducing agent. N₂H₄·2H₂O was a mild reducing agent suggesting that all processes could be operated at room temperature. The as-prepared Cu NCs showed red fluorescence with a peaking center at 620 nm (quantum yield 4.1%). The fluorescence of the as-prepared BSA-Cu NCs was responsive to pH in that the intensity of fluorescence increased rapidly by decreasing the pH from 12 to 6. Besides, with an arresting set of features including water-dispersibility, red fluorescence, good biocompatibility, surface-bioactivity and small size, the resultant BSA-Cu NCs could be used as probes for cellular imaging and catalysis. In this study, CAL-27 cells and the reaction of oxidation of styrene are used as models to achieve fluorescence imaging and elucidate the catalytic activity of the as-prepared BSA-Cu NCs.
authors.affiliation: China-Australia Joint Research Centre for Functional Molecular Materials, School of Chemical & Material Engineering, Jiangnan University, Wuxi 214122, P. R. China. chizhang@jiangnan.edu.cn.
authors.forename: Chan
authors.initials: C
authors.lastname: Wang
authors.forename: Chuanxi
authors.initials: C
authors.lastname: Wang
authors.forename: Lin
authors.initials: L
authors.lastname: Xu
authors.forename: Hao
authors.initials: H
authors.lastname: Cheng
authors.forename: Quan
authors.initials: Q
authors.lastname: Lin
authors.forename: Chi
authors.initials: C
authors.lastname: Zhang
mesh_terms: D000818:Animals; D001672:Biocompatible Materials / Q000737:chemistry; D002384:Catalysis; D002417:Cattle; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D002942:Circular Dichroism; D003300:Copper / Q000737:chemistry*; D005453:Fluorescence; D006801:Humans; D006834:Hydrazines / Q000737:chemistry; D006863:Hydrogen-Ion Concentration; D049449:Luminescence; D053768:Metal Nanoparticles / Q000737:chemistry*; D008853:Microscopy / Q000295:instrumentation / Q000379:methods*; D046529:Microscopy, Electron, Transmission; D036103:Nanotechnology; D010100:Oxygen / Q000737:chemistry; D010777:Photochemistry; D011506:Proteins / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012995:Solubility; D020058:Styrene / Q000737:chemistry; D013499:Surface Properties; D014867:Water / Q000737:chemistry
chemical_list: D001672:Biocompatible Materials; D006834:Hydrazines; D011506:Proteins; D014867:Water; D012710:Serum Albumin, Bovine; C029424:hydrazine; D020058:Styrene; D003300:Copper; D010100:Oxygen