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A sensitive and selective electrochemical method was developed for simultaneous determination of uric acid and xanthine using the nano boron doped ceria modified glassy carbon paste electrode (nano-B-CeO2/GCPE). The proposed sensor exhibited an excellent catalytic activity, high sensitivity and good selectivity toward the oxidation of uric acid and xanthine. The potential mutual interference of uric acid (UA), xanthine (XA), dopamine (DA) and ascorbic acid (AA) were examined indicting that their oxidation take place independently at the nano-B-CeO2/GCPE sensor. For simultaneous detection by synchronous change of the concentration of UA and XA, the linear ranges were 0.42–11.87 μM and 0.07–2.02 μM with detection limits of 5.39 × 10− 9 M and 2.36 × 10− 9 M, respectively. The proposed method was successfully applied to simultaneous determination of UA and XA in human urine and serum samples with satisfactory results.

A sensitive and selective electrochemical method was developed for simultaneous determination of uric acid and xanthine using the nano boron doped ceria modified glassy carbon paste electrode (nano-B-CeO2/GCPE). The proposed sensor exhibited an excellent catalytic activity, high sensitivity and good selectivity toward the oxidation of uric acid and xanthine. The potential mutual interference of uric acid (UA), xanthine (XA), dopamine (DA) and ascorbic acid (AA) were examined indicting that their oxidation take place independently at the nano-B-CeO2/GCPE sensor. For simultaneous detection by synchronous change of the concentration of UA and XA, the linear ranges were 0.42–11.87 μM and 0.07–2.02 μM with detection limits of 5.39 × 10− 9 M and 2.36 × 10− 9 M, respectively. The proposed method was successfully applied to simultaneous determination of UA and XA in human urine and serum samples with satisfactory results.

Hibifolin (HBF), a flavonol glycoside derived from herbal plants, possessed a strong protective activity against cell death induced by aggregated β–amyloid (Aβ). Therefore, detection of neuroprotective HBF in biological system of great significance for fundamental study in medicine field. To address this critical need, we herein developed a novel electrochemical sensor based on Zn–In2O3 nanorods coated glassy carbon microspheres paste electrode (Zn–In2O3NRs/GCPE) for HBF detection. Zn–In2O3NRs were successfully synthesized via a facile sol gel combustion method for the first time and assessed for their structural and morphological changes due to Zn doping into In2O3NPs by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The fabricated Zn–In2O3NRs/GCPE displayed high effective surface area, more reaction sites and excellent electrochemical catalytic activity toward the oxidation of neuroprotective HBF. Under the optimum conditions, the sensor showed fast and sensitive current response to HBF over a wide range of 1.95 × 10− 8–3.25 × 10− 6 M with a low detection limit of 3.10 × 10− 10 M (S/N = 3). Furthermore, this electrochemical sensor was successfully applied for the determination of HBF in spiked human biological fluids and in the flowers of hibiscus vitifolius with good accuracy and precision.

Hibifolin (HBF), a flavonol glycoside derived from herbal plants, possessed a strong protective activity against cell death induced by aggregated β–amyloid (Aβ). Therefore, detection of neuroprotective HBF in biological system of great significance for fundamental study in medicine field. To address this critical need, we herein developed a novel electrochemical sensor based on Zn–In2O3 nanorods coated glassy carbon microspheres paste electrode (Zn–In2O3NRs/GCPE) for HBF detection. Zn–In2O3NRs were successfully synthesized via a facile sol gel combustion method for the first time and assessed for their structural and morphological changes due to Zn doping into In2O3NPs by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The fabricated Zn–In2O3NRs/GCPE displayed high effective surface area, more reaction sites and excellent electrochemical catalytic activity toward the oxidation of neuroprotective HBF. Under the optimum conditions, the sensor showed fast and sensitive current response to HBF over a wide range of 1.95 × 10− 8–3.25 × 10− 6 M with a low detection limit of 3.10 × 10− 10 M (S/N = 3). Furthermore, this electrochemical sensor was successfully applied for the determination of HBF in spiked human biological fluids and in the flowers of hibiscus vitifolius with good accuracy and precision.

Chalcogenide Se75Sb10In15 thin films of different thickness (50–300 nm) are deposited using thermal evaporation technique. The thermogram of the chalcogenide bulk Se75Sb10In15 is obtained using a differential scanning calorimetry (DSC). The crystallization temperature Tc, peak crystallization temperature Tp and melting temperature Tm, are identified. The X-ray diffraction (XRD) examination indicates the crystallinity of the as-deposited film decreases with increasing of thickness. Optical transmission and reflection spectra are recorded in the wavelength range of the incident photons from 250 to 2500 nm. It is found that the film thickness affects the absorption coefficient, refractive index, extinction coefficient and the width of the tails of localized states in the gap region. The absorption mechanism of the as-deposited films is a direct allowed transition. The optical band gap energy (Eg) decreases from 3.31 to 2.51 eV with increasing the film thickness from 50 to 300 nm. The behavior of Eg is explained on the basis of the structure disorders in the thicker films. The effect of the film thickness on the single-oscillator and dispersion energies is studied by the dispersion analyses of the refractive index.

Chalcogenide Se75Sb10In15 thin films of different thickness (50–300 nm) are deposited using thermal evaporation technique. The thermogram of the chalcogenide bulk Se75Sb10In15 is obtained using a differential scanning calorimetry (DSC). The crystallization temperature Tc, peak crystallization temperature Tp and melting temperature Tm, are identified. The X-ray diffraction (XRD) examination indicates the crystallinity of the as-deposited film decreases with increasing of thickness. Optical transmission and reflection spectra are recorded in the wavelength range of the incident photons from 250 to 2500 nm. It is found that the film thickness affects the absorption coefficient, refractive index, extinction coefficient and the width of the tails of localized states in the gap region. The absorption mechanism of the as-deposited films is a direct allowed transition. The optical band gap energy (Eg) decreases from 3.31 to 2.51 eV with increasing the film thickness from 50 to 300 nm. The behavior of Eg is explained on the basis of the structure disorders in the thicker films. The effect of the film thickness on the single-oscillator and dispersion energies is studied by the dispersion analyses of the refractive index.

Chalcogenide Se75Sb10In15 thin films of different thickness (50–300 nm) are deposited using thermal evaporation technique. The thermogram of the chalcogenide bulk Se75Sb10In15 is obtained using a differential scanning calorimetry (DSC). The crystallization temperature Tc, peak crystallization temperature Tp and melting temperature Tm, are identified. The X-ray diffraction (XRD) examination indicates the crystallinity of the as-deposited film decreases with increasing of thickness. Optical transmission and reflection spectra are recorded in the wavelength range of the incident photons from 250 to 2500 nm. It is found that the film thickness affects the absorption coefficient, refractive index, extinction coefficient and the width of the tails of localized states in the gap region. The absorption mechanism of the as-deposited films is a direct allowed transition. The optical band gap energy (Eg) decreases from 3.31 to 2.51 eV with increasing the film thickness from 50 to 300 nm. The behavior of Eg is explained on the basis of the structure disorders in the thicker films. The effect of the film thickness on the single-oscillator and dispersion energies is studied by the dispersion analyses of the refractive index.

Chalcogenide Se50Te20S30 thin film of different thickness was deposited using thermal evaporation technique. The thermogram of the chalcogenide bulk Se50- Te20S30 was obtained using a differential scanning calorimetry (DSC) with heating rate of 7.5 K/min. The glass transition temperature Tg, crystallization temperature Tc and peak crystallization temperature Tp were identified. The X-ray diffraction (XRD) examination indicates the amorphous nature of the as-deposited film and polycrystalline structure of the thermal annealed ones. The dark electrical resistivity (q) measurements were taken in temperature range (300–500 K) and thickness range (200–450 nm). Analysis of the electrical resistivity results revealed two types of conduction mechanisms: conduction due to extended states in the temperature range (T[Tc) and variable range hopping in the temperature range (TTc). The effect of the heat treatment and thickness on the density of localized states at the Fermi level N(EF) and hopping parameters were studied.

Chalcogenide Se50Te20S30 thin film of different thickness was deposited using thermal evaporation technique. The thermogram of the chalcogenide bulk Se50- Te20S30 was obtained using a differential scanning calorimetry (DSC) with heating rate of 7.5 K/min. The glass transition temperature Tg, crystallization temperature Tc and peak crystallization temperature Tp were identified. The X-ray diffraction (XRD) examination indicates the amorphous nature of the as-deposited film and polycrystalline structure of the thermal annealed ones. The dark electrical resistivity (q) measurements were taken in temperature range (300–500 K) and thickness range (200–450 nm). Analysis of the electrical resistivity results revealed two types of conduction mechanisms: conduction due to extended states in the temperature range (T[Tc) and variable range hopping in the temperature range (TTc). The effect of the heat treatment and thickness on the density of localized states at the Fermi level N(EF) and hopping parameters were studied.