Fabrication of an Extremely Cheap Poly(3,4-ethylenedioxythiophene) Modified Pencil Lead Electrode for Effective Hydroquinone Sensing.

Hydroquinone (HQ) is one of the major deleterious metabolites of benzene in the human body, which has been implicated to cause various human diseases. In order to fabricate a feasible sensor for the accurate detection of HQ, we attempted to electrochemically modify a piece of common 2B pencil lead (PL) with the conductive poly(3,4-ethylenedioxythiophene) or PEDOT film to construct a PEDOT/PL electrode. We then examined the performance of PEDOT/PL in the detection of hydroquinone with different voltammetry methods.

Synthesis of MOF525/PEDOT Composites as Microelectrodes for Electrochemical Sensing of Dopamine.

Dopamine (DA) is an important neurotransmitter responsible for the functions and activities of multiple systems in human. Electrochemical detection of DA has the advantages of fast analysis and cost-effectiveness, while a regular electrode probe is restricted to laboratory use because the probe size is too large to be suitable for an in vivo or in vitro analysis. In this study, we have developed porphyrin-based metal organic framework (MOF525) and poly(3,4-ethylenedioxythiophene) (PEDOT)-based composites to modify microelectrode for DA detection.

High-Density Plasmonic Nanoparticle Arrays Deposited on Nanoporous Anodic Alumina Templates for Optical Sensor Applications.

This study demonstrates a new, robust, and accessible deposition technique of metal nanoparticle arrays (NPAs), which uses nanoporous anodic alumina (NAA) as a template for capillary force-assisted convective colloid (40, 60, and 80 nm diameter Au) assembly. The NPA density and nanoparticle size can be independently tuned by the anodization conditions and colloid synthesis protocols. This enables production of non-touching variable-density NPAs with controllable gaps in the 20-60 nm range.

Quantification of DNA by a Thermal-Durable Biosensor Modified with Conductive Poly(3,4-ethylenedioxythiophene).

The general clinical procedure for viral DNA detection or gene mutation diagnosis following polymerase chain reaction (PCR) often involves gel electrophoresis and DNA sequencing, which is usually time-consuming. In this study, we have proposed a facile strategy to construct a DNA biosensor, in which the platinum electrode was modified with a dual-film of electrochemically synthesized poly(3,4-ethylenedioxythiophene) (PEDOT) resulting in immobilized gold nanoparticles, with the gold nanoparticles easily immobilized in a uniform distribution. The DNA probe labeled with a SH group was then assembled to the fabricated electrode and employed to capture the target DNA based on the complementary sequence.

Molecular Assembly of a Durable HRP-AuNPs/PEDOT:BSA/Pt Biosensor with Detailed Characterizations.

In this study, we provided the detailed characterizations of our recent HRP-AuNPs/PEDOT:BSA/Pt biosensor, constructed through a simple fabrication procedure with improved stability and good sensitivity. Raman and Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy not only confirmed the synthesis of conductive PEDOT where BSA was the template for the polymerization, but also provided further insights into the stable immobilization of AuNP on the PEDOT:BSA film. Scanning electron microscopy revealed that the attachment of AuNPs were stable under a high salt environment.

A Novel Conductive Poly(3,4-ethylenedioxythiophene)-BSA Film for the Construction of a Durable HRP Biosensor Modified with NanoAu Particles.

In this study, we have investigated the contribution of bovine serum albumin (BSA) to the durability of the electrochemically synthesized poly(3,4-ethylenedioxythiophene) (PEDOT) film on a platinum (Pt) electrode. The electrode was capable to effectively adsorb the nano Au particles (AuNPs) to form a uniform layout, which was then able to immobilize the horseradish peroxidase (HRP) to construct a functional HRP/AuNPs/PEDOT(BSA)/Pt biosensor. Cyclic voltammetry was employed to evaluate the performance of the biosensor through the measurement of hydrogen peroxide.

Chitosan-coated electrospun PLA fibers for rapid mineralization of calcium phosphate.

In this work, hydroxyapatite (HA) mineralized on chitosan (CS)-coated poly(lactic acid) (PLA) nanofiber mat was prepared and compared in terms of mineralization characteristics. Significant calcium phosphate crystals formed on various concentrations of CS-coated PLA fiber mat with better uniformity after 2h of incubation in 10 times simulated body fluid (10× SBF). X-ray diffraction results further indicated that the composition of the deposited mineral was a mixture of dicalcium phosphate dehydrates and apatite.

A two-stage enzymatic synthesis of conductive poly(3,4-ethylenedioxythiophene).

The conductive polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), possesses attractive properties that show the potential applications in many fields. In this study, we have proposed a two-stage enzymatic synthesis of conductive PEDOT. Horseradish peroxidase (HRP) acts as the catalyst to promote the generation of EDOT free radicals followed by the polymerization under the room temperature in the presence of poly(sodium 4-styrenesulfonate) (PSS), then a mild heating process is employed for further chain extension.

The potential application of a poly(3,4-ethylenedioxythiopene) modified platinum DNA biosensor in mutation analysis.

In this study, we have fabricated a label free DNA biosensor by modifying the platinum wire with electrochemically synthesized poly(3,4-ethylenedioxythiopene) and poly(p-aminobenzoic acid). A designed single-strand DNA oligo was immobilized with the carboxyl group of poly(p-aminobenzoic acid) and served as the probe, a target DNA was then hybridized with the probe under a proper condition. Differential pulse voltammetry was performed to characterize the hybridization efficiency in the presence of daunorubicin hydrochloride that was able to be intercalated into the hybridized double-strand DNA and possessed the redox activity.

Immobilization of HRP in Mesoporous Silica and Its Application for the Construction of Polyaniline Modified Hydrogen Peroxide Biosensor.

Polyaniline (PANI), an attractive conductive polymer, has been successfully applied in fabricating various types of enzyme-based biosensors. In this study, we have employed mesoporous silica SBA-15 to stably entrap horseradish peroxidase (HRP), and then deposited the loaded SBA-15 on the PANI modified platinum electrode to construct a GA/SBA-15(HRP)/PANI/Pt biosensor. The mesoporous structures and morphologies of SBA-15 with or without HRP were characterized.

Eliminating the Interference of Oxygen for Sensing Hydrogen Peroxide with the Polyaniline Modified Electrode.

Polyaniline (PANI) has been shown to possess excellent catalytic activity toward oxygen reduction, however, this molecule may interfere with the electrochemical measurement of other targets when using a polyaniline modified platinum (PANI/Pt) electrode. In this study, we have demonstrated the considerable effects of dissolved oxygen on the sensing of hydrogen peroxide with the PANI/Pt electrode. Accordingly, we proposed a strategy to eliminate the influence of dissolved oxygen with oxygen scavengers.

Enhancing the sensitivity and stability of HRP/PANI/Pt electrode by implanted bovine serum albumin.

Polyaniline (PANI) is considered as one of the most fascinating conductive polymers in fabricating enzyme-based biosensors. Nevertheless, to improve both sensitivity and stability of the PANI-modified biosensor has been and continues to be a technical challenge. In this study, we have electrochemically synthesized the PANI film on a platinum (Pt) electrode and then used this electrode to construct a horseradish peroxidase (HRP)-based biosensor for the detection of hydrogen peroxide (H(2)O(2)).

Chronic renal failure rats are highly sensitive to aristolochic acids, which are nephrotoxic and carcinogenic agents.

Aristolochic acid (AA), a component of some Chinese herbal medicines, may cause Chinese Herbs Nephropathy (CHN) and multi-systemic tumors by the formation of AA-DNA adducts. In this study, we established an animal model to further characterize the mechanisms of AA-induced diseases. Our results indicated that AA significantly inhibited rat growth in terms of weight gain.

Human MutY homolog, a DNA glycosylase involved in base excision repair, physically and functionally interacts with mismatch repair proteins human MutS homolog 2/human MutS homolog 6.

Adenines mismatched with guanines or 7,8-dihydro-8-oxo-deoxyguanines that arise through DNA replication errors can be repaired by either base excision repair or mismatch repair. The human MutY homolog (hMYH), a DNA glycosylase, removes adenines from these mismatches. Human MutS homologs, hMSH2/hMSH6 (hMutSalpha), bind to the mismatches and initiate the repair on the daughter DNA strands.