CuInS2 quantum dots as a near-infrared fluorescent probe for detecting thrombin in human serum.
This paper describes a novel, simple method for the highly sensitive and selective detection of thrombin using fibrinogen (Fib) and CuInS(2) quantum dots (QDs) as biosensing probes. Water-soluble near-infrared CuInS(2) QDs capped by mercaptopropionic acid (MPA) were directly synthesized by a hydrothermal method. Addition of fibrinogen to the CuInS(2) QDs solution led to the formation of a Fib-CuInS(2) QDs complex through electrostatic interactions and hydrogen bonding, and resulting in the enhancement of photoluminescence (PL) intensity and a red shift of the PL peak. Once thrombin was introduced into the Fib-CuInS(2) QDs system, it catalyzed the polymerization of the free and conjugated fibrinogen species to form insoluble fibrillar fibrin-CuInS(2) QDs agglutinates. After centrifugation, the PL intensity of the supernatants decreased upon increasing the concentration of thrombin. This Fib-CuInS(2) QDs probe provided a highly specific selectivity and a linear detection of thrombin in the range of 6.7 × 10(-11) to 3.9 × 10(-7) mol L(-1) with a detection limit (LOD) of about 8.7 × 10(-12) mol L(-1), and realized the thrombin detection in human serum samples directly. Compared with those obtained by using other nanomaterials and aptamer-based detection methods, this approach provided a lower LOD for thrombin detection. The proposed approach provides a simple and fast-responding procedure, which might hold a promising potential for application in the diagnosis of diseases associated with coagulation abnormalities and cancers.
Department of Analytical Chemistry, College of Chemistry, Jilin University, Qianwei Road 10, Changchun 130012, China.
Xue
X
Gao
Xingcen
X
Liu
Zihan
Z
Lin
Siyu
S
Liu
Xingguang
X
Su
D003300:Copper / Q000737:chemistry*; D005340:Fibrinogen; D005456:Fluorescent Dyes; D006801:Humans; D007204:Indium / Q000737:chemistry*; D057230:Limit of Detection; D049449:Luminescence; D045663:Quantum Dots; D013447:Sulfites / Q000737:chemistry*; D013917:Thrombin / Q000032:analysis*
D005456:Fluorescent Dyes; D013447:Sulfites; D007204:Indium; D003300:Copper; D005340:Fibrinogen; D013917:Thrombin