Electrogenerated chemiluminescence from CdS hollow spheres composited with carbon nanofiber and its sensing application.
The electrogenerated chemiluminescence (ECL) from nanometre-sized CdS hollow spheres and carbon nanofiber (CdSHS-CNF) nanocomposites in aqueous solution and their sensing applications were studied by entrapping them in carbon paste. The CdSHS-CNF nanocomposites exhibited a peak at -1.02 V (vs. Ag/AgCl) in 0.1 M pH 8.0 PBS containing 20 mM H(2)O(2) during the cyclic sweep between 0 and -1.2 V at 40 mV s(-1). Compared with CdS hollow spheres (CdSHS), carbon nanofiber (CNF) and CdS nanocrystals and carbon nanofiber (CdSNC-CNF) nanocomposites, CdSHS-CNF not only enhanced the electrochemiluminescent intensity but also decreased the ECL starting potentials. Furthermore, by immobilizing cholesterol oxidase (ChOx) on CdSHS-CNF nanocomposites modified electrode, a sensitive and selective method was developed for detection of cholesterol using oxygen as a coreactant which captured more electrons from electrochemically reduced CdSHS-CNF than H(2)O(2). Under optimal conditions, the sensor could be used for the determination of cholesterol from 1 × 10(-6) to 4.4 × 10(-4) M with a correlation coefficient of 0.9991 and a detection limit was 8 × 10(-7) M at 3σ. The unique ECL intensity and stability of CdSHS-CNF would promote the application of nanometre-sized semiconductor hollow spheres based composites in fabricating sensors for chemical and biochemical analysis.
Zhu
Qinshu
Q
Jiangsu Key Laboratory of Biofunctional Materials, Laboratory of Electrochemistry, College of Chemistry and Environmental Science, Nanjing Normal University, Nanjing, 210097, P. R. China.
Han
Min
M
Wang
Huaisheng
H
Liu
Lili
L
Bao
Jianchun
J
Dai
Zhihui
Z
Shen
Jian
J
D015374:Biosensing Techniques / Q000379:methods*; D019187:Cadmium Compounds / Q000737:chemistry*; D002244:Carbon / Q000737:chemistry*; D002784:Cholesterol / Q000032:analysis; D002789:Cholesterol Oxidase / Q000737:chemistry / Q000378:metabolism; D055664:Electrochemical Techniques / Q000379:methods; D004566:Electrodes; D004800:Enzymes, Immobilized / Q000737:chemistry / Q000378:metabolism; D008163:Luminescent Measurements / Q000379:methods*; D057139:Nanofibers / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*
D019187:Cadmium Compounds; D004800:Enzymes, Immobilized; D013440:Sulfides; C034939:cadmium sulfide; D002244:Carbon; D002784:Cholesterol; D002789:Cholesterol Oxidase