Conducting polymers possess good conductivity, can be easily modified, have a particular redox activity. Noble metal nanomaterials, in turn, possess high conductivity, catalytic properties and large surface-to-volume ratios. Synergistic materials consisting of both conducting polymer and metal nanomaterial therefore are most useful materials for use in electrochemical immunosensors with improved sensitivity and specificity. This review (with 75 references) gives an overview on advances in conducting polymer based noble metal nanomaterial hybrids for amperometric immunoassay of the 13 most common tumor markers. The review is divided into the following sections: (1) Polyaniline based noble metal nanomaterial hybrids; (2) Polyaniline derivative-based noble metal nanomaterial hybrids; (3) Polypyrrole-based noble metal nanomaterial hybrids. A final section covers future perspectives regarding challenges on the design of electrochemical immunoassays.
Graphical abstract Advances on conducting polymer and noble metal nanomaterial hybrids for amperometric immunoassay of tumor marker are reviewed. Future perspectives regarding challenges on the construction of electrochemical immunosensing interface for tumor marker are discussed.
In this paper, we report on the direct electrodeposition of magnetic hybrids based on magnetite nanoparticle containing poly(3,4-ethylenedioxythiophene) (PEDOT) and polyaniline (PANI) in the presence of magnetite and the special conducting electrolyte, potassium tetraoxalate. The optimal electropolymerization processes (monitored by scanning electron microscopy) were performed potentiostatically, and the incorporation of the iron oxide into the polymeric film was demonstrated by Diffuse Reflectance UV-Visible Spectroscopy (DR-UV?Cvis) and transmission electron microscopic measurements. Electrochemical quartz crystal nanobalance proved that both the neat PEDOT and the PEDOT/magnetite hybrid show anion exchange behaviour. Cyclic voltammetric features of the polymers and their hybrids exhibited an enhanced redox capacity of the composites. The difference in the effect of the scanning rate on this capacity increase in the two cases could be interpreted by the assumption that the presence of magnetite manifests dominantly in the enhanced intrinsic electroactivity of PANI, while in the case of the PEDOT composite, the extra charge is more connected to the charge surplus originating from the redox activity of the nanoparticles. 相似文献
Ce(III) oxide was synthesized under the protection of nitrogen gas, which had strong ability to reduce noble metal ions (e.g., Au, Pd ions) into metallic forms under oxygen-free conditions. On the basis of the surface redox reaction between the Ce(III) oxide support and noble metal ions, an effective and novel approach was presented to prepare noble metal/CeO(2) nanocatalysts, and a series of AuPd/CeO(2) nanocomposites with different Au:Pd molar ratios and metal loadings were obtained in the absence of any extra reducing and protective agents. The resultant composites were characterized by different techniques including X-ray diffraction, transmission electron microspectroscopy, X-ray photoelectron microspectroscopy, and ICP-AES analysis. It was demonstrated that in the AuPd/CeO(2) composites the content of Ce(III) reached about 30%, and the AuPd bimetallic particles with average size of 2.6 or 3.3 nm and narrow size distribution were uniformly distributed on the CeO(2) nanorods. The AuPd/CeO(2) composites were found to be excellent heterogeneous nanocatalysts for the selective oxidation of benzyl alcohol under solvent-free conditions. It was shown that all the AuPd/CeO(2) catalysts exhibited good selectivity toward benzaldehyde; especially, the catalyst with Au:Pd = 1:5 and metal loading of 1.2 wt % displayed extremely high activity with a TOF = 30.1 s(-1) at 160 °C. 相似文献
The transmetalation reaction between a sacrificial nanoparticle and more noble metal ions in solution has emerged as a novel method for creating unique hollow and bimetallic nanostructures. In this report, we investigate the possibility of carrying out the transmetalation reaction between hydrophobic silver nanoparticles assembled and constrained at the air-water interface and subphase gold ions. We observe that facile reduction of the subphase gold ions by the sacrificial silver nanoparticles occurs resulting in the formation of elongated gold nanostructures that appear to cross-link the sacrificial silver particles. This transmetalation reaction may be modulated by the insertion of an electrostatic barrier in the form of an ionizable lipid monolayer between the silver nanoparticles and the aqueous gold ions that impacts the gold nanoparticle assembly. Transmetalation reactions between nanoparticles constrained into a close-packed structure and appropriate metal ions could lead to a new strategy for metallic cross-linking of nanoparticles and generation of coatings with promising optoelectonic behavior. 相似文献
In this paper, we report on the direct electrodeposition of magnetic hybrids based on magnetite nanoparticle containing poly(3,4-ethylenedioxythiophene) (PEDOT) and polyaniline (PANI) in the presence of magnetite and the special conducting electrolyte, potassium tetraoxalate. The optimal electropolymerization processes (monitored by scanning electron microscopy) were performed potentiostatically, and the incorporation of the iron oxide into the polymeric film was demonstrated by Diffuse Reflectance UV-Visible Spectroscopy (DR-UV–vis) and transmission electron microscopic measurements. Electrochemical quartz crystal nanobalance proved that both the neat PEDOT and the PEDOT/magnetite hybrid show anion exchange behaviour. Cyclic voltammetric features of the polymers and their hybrids exhibited an enhanced redox capacity of the composites. The difference in the effect of the scanning rate on this capacity increase in the two cases could be interpreted by the assumption that the presence of magnetite manifests dominantly in the enhanced intrinsic electroactivity of PANI, while in the case of the PEDOT composite, the extra charge is more connected to the charge surplus originating from the redox activity of the nanoparticles.
The electrochemical polymerization of aniline was studied in polymer matrices (polyamid-12 and polyvinyl alcohol) on an electrode in the potential cycling mode from –0.2 to +0.8 V vs. SCE. The indices of this process such as the potentials and currents of the polyaniline redox peaks, polymerization rate, and properties of the conducting composite formed depend on the nature of the matrix polymer and are a function of the extent of interaction of this matrix polymer with aniline and polyaniline. 相似文献