Ultrasensitive electrochemical immunoassay for melanoma cells using mesoporous polyaniline.

We report the development of an antibody (anti-MC1R antibody)-functionalized polyaniline nanofibers modified screen-printed electrode capable of efficient electrochemical detection of melanoma cells at levels (1 cell per mL) not readily achieved by other methods. This immunosensor is highly selective in its detection of melanoma cells over normal human cells.

Hydrothermal synthesis of CuO micro-/nanostructures and their applications in the oxidative degradation of methylene blue and non-enzymatic sensing of glucose/H2O2.

In this paper, we report on the amino acids-/citric acid-/tartaric acid-assisted morphologically controlled hydrothermal synthesis of micro-/nanostructured crystalline copper oxides (CuO). These oxides were characterized by means of X-ray diffraction, nitrogen sorption, scanning electron microscopy, Fourier transform infrared, and UV-visible spectroscopy. The surface area of metal oxides depends on the amino acid used in the synthesis. The formation mechanisms were proposed based on the experimental results, which show that amino acid/citric acid/tartaric acid and hydrothermal time play an important role in tuning the morphology and structure of CuO. The catalytic activity of as-synthesized CuO was demonstrated by catalytic oxidation of methylene blue in the presence of hydrogen peroxide (H(2)O(2)). CuO synthesized using tyrosine was found to be the best catalyst compared to a variety of CuO synthesized in this study. CuO (synthesized in this study)-modified electrodes were used for the construction of non-enzymatic sensors, which displayed excellent electrocatalytic response for the detection of H(2)O(2) and glucose compared to conventional CuO. The high electrocatalytic response observed for the CuO synthesized using tyrosine can be correlated with the large surface area, which enhances the accessibility of H(2)O(2)/glucose molecule to the active site that results in high observed current. The methodology adopted in the present study provides a new platform for the fabrication of CuO-based high-performance glucose and other biosensors.

Synthesis of mesostructured polyaniline using mixed surfactants, anionic sodium dodecylsulfate and non-ionic polymers and their applications in H2O2 and glucose sensing.

Mesostructured polyaniline was prepared by the self-assembly of a mixture of an anionic surfactant, sodium dodecylsulfate and a non-ionic polymeric surfactant (polyethylene glycol, and block-co-polymers such as Pluronic P123 and Brij-35). Materials were characterized by a complementary combination of X-ray diffraction, Scanning electron microscopy, Fourier-transform infrared spectrometer and UV-visible spectrophotometer. Mesostructured polyaniline was used for construction of biosensor, which displayed excellent electrocatalytic response for the detection of H(2)O(2) and glucose compared to conventional polyaniline. The electrocatalytic response observed in the case of mesostructured polyaniline can be correlated with the large surface area and nanopores which enhances the accessibility of H(2)O(2)/glucose molecule to the active site that result in high observed current. The methodology adopted in the present study provides a new platform for the fabrication of polyaniline based high-performance glucose and other biosensors.

Synthesis of nanoporous metal oxides through the self-assembly of phloroglucinol-formaldehyde resol and tri-block copolymer.

A versatile route to synthesize nanoporous crystalline metal oxides has been developed through the self-assembly of phloroglucinol-formaldehyde resol and tri-block copolymer templates. Materials were characterized by a complementary combination of X-ray diffraction, nitrogen sorption, and transmission electron microscopy. Metal oxides synthesized using this route have remarkably high surface area when compared with the commercial samples. The surface area of metal oxides decreased upon calcination at higher temperatures. However, the surface area was still much higher when compared with the commercial samples. TEM investigation reveals that upon calcination at higher temperature, the size of the crystal increased but the short range order was merely disturbed. The analyses show that the present method is suitable as a direct route to synthesize crystalline nanoporous metal oxides. Hydrogen bonding plays a key role in the preferential arrangement of porous metal-carbon structure in the domain of tri-block copolymer. The nanoporous metal oxides with ordered mesoporous structure, high surface area, and crystalline framework are expected to show significant improvement in catalysis and nano-technology.