Cerium phosphate nanotubes: synthesis, characterization and biosensing.
Cerium phosphate (CeP) nanotubes have been synthesized and confirmed by x-ray diffraction (XRD) and transmission electron microscopy (TEM). The 1D nanomaterial has a monoclinic crystal structure with a mean width of 15-20 nm and a length up to several micrometers. The nanotubes have been employed as electrode substrates for immobilization and direct electrochemistry of heme proteins/enzymes with myoglobin (Mb) as a model. The electrochemical characteristics of the Mb-CeP/GC electrode were studied by voltammetry. After being immobilized on the nanotubes, Mb can keep its natural structure and undergo effective direct electron transfer reaction with a pair of well-defined redox peaks at -(367 +/- 3) mV (pH 7.5). The apparent electron transfer rate constant is (9.1 +/- 1.4) s(-1). The electrode displays good features in the electrocatalytic reduction of H(2)O(2), and thus can be used as a biosensor for detecting the substrate with a low detection limit (0.5 +/- 0.05 microM), a wide linear range (0.01-2 mM), high sensitivity (14.4 +/- 1.2 microA mM(-1)), as well as good stability and reproducibility. CeP nanotubes can become a simple and effective biosensing platform for the integration of heme proteins/enzymes and electrodes, which can provide analytical access to a large group of enzymes for a wide range of bioelectrochemical applications.
Meng
Ling
L
Jiangsu Key Laboratory of Biofunctional Materials, College of Chemistry and Environmental Science, Nanjing Normal University, Nanjing 210097, People's Republic of China.
Yang
Lige
L
Zhou
Bo
B
Cai
Chenxin
C
D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation*; D002384:Catalysis; D002563:Cerium / Q000737:chemistry*; D002942:Circular Dichroism; D004563:Electrochemistry; D004566:Electrodes; D004583:Electrons; D006736:Horses; D006863:Hydrogen-Ion Concentration; D009211:Myoglobin / Q000737:chemistry; D043942:Nanotubes / Q000737:chemistry* / Q000648:ultrastructure; D010710:Phosphates / Q000737:chemistry*; D015203:Reproducibility of Results; D012996:Solutions; D013056:Spectrophotometry, Ultraviolet
D009211:Myoglobin; D010710:Phosphates; D012996:Solutions; D002563:Cerium; C048083:cerium phosphate