title: Cation exchange-based facile aqueous synthesis of small, stable, and nontoxic near-infrared Ag₂Te/ZnS core/shell quantum dots emitting in the second biological window.
abstract: Facile aqueous synthesis of near-infrared Ag(2)Te quantum dots (QDs) and Ag(2)Te/ZnS core/shell QDs emitting in the second biological window is reported. The QD synthesis is based on a straightforward cation exchange process between CdTe QDs and Ag(+) ions conducted in aqueous solution. The prepared Ag(2)Te QDs possess near-infrared emission ranging from 900 to 1300 nm and a quantum yield up to 2.1%. A ZnS shell was grown on the Ag(2)Te QD to further enhance the photoluminescence intensity with a quantum yield of 5.6%. These Ag(2)Te/ZnS core/shell QDs possess robust colloidal stability and photostability with minimum photoluminescence fluctuation upon incubation for 72 h in biological buffer or continuous laser excitation for 120 min. Also, These QDs possess small hydrodynamic size (∼7.6 nm) and are non-cytotoxic to human cells, which is ideal for optical bioimaging in the second biological window.
authors: The Key Lab of Health Chemistry and Molecular Diagnosis of Suzhou, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, 215123, P R China.
authors: Chi
authors: C
authors: Chen
authors: Xuewen
authors: X
authors: He
authors: Li
authors: L
authors: Gao
authors: Nan
authors: N
authors: Ma
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation*; D002477:Cells / Q000187:drug effects; D060326:Chemistry Techniques, Synthetic / Q000379:methods*; D006367:HeLa Cells; D006801:Humans; D011108:Polymers / Q000138:chemical synthesis* / Q000737:chemistry / Q000633:toxicity; D045663:Quantum Dots; D018030:Silver Compounds / Q000737:chemistry; D013440:Sulfides / Q000737:chemistry*; D013499:Surface Properties; D013691:Tellurium / Q000737:chemistry*; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D011108:Polymers; D018030:Silver Compounds; D013440:Sulfides; D017967:Zinc Compounds; C031238:zinc sulfide; D013691:Tellurium