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In this work, molybdenum disulfide (MoS2) nanorods (NRs) were prepared by a simple hydrothermal method. A sensitive electrochemical glucose biosensor was developed based on the immobilization of glucose oxidase (GOx) on MoS2 NRs modified glassy carbon electrode (GCE). The SnO2 NRs were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy dispersive X-ray spectroscopy (EDS). SnO2 NRs have large specific area and can load large amounts of GOx molecules. The cyclic voltammetry (CV) of GOx/MoS2 NR/GCE exhibited a linear relationship between the peak current density of CV with glucose concentration in the range of 3.0 mM to 7.0 mM with the limit of detection (LOD) of 3.0 mM and high sensitivity of mA.mM. The parameters affecting the oxidation current density such as pH, temperature, GOx concentration were also investigated. This study demonstrates the feasibility of realizing inexpensive, reliable, and highly effective performance glucose biosensors using MoS2 nanorods.

TiO2 nanotubes were successfully synthesized by electrochemical method. A fluoride salt mixture was used as an electrolyte for synthesizing TiO2 nanotubes on titanium substrates. In this work, we have reported the synthesis procedure of TiO2 nanotubes and investigated the corrosion resistance of TiO2 nanotubes coated on the Ti substrate. FE-SEM was used to observe the morphology and determine the size of the TiO2 nanotubes. The phase formation and crystal quality of TiO2 nanotubes were studied by XRD measurements. One-microliter distilled water droplets were used to define the wettability of the TiO2 nanotube surfaces by measuring the contact angle. The corrosion resistance behavior of specimens was analyzed in the simulated body fluid solution (SBF) using potentiodynamic polarization tests for potential application as implants.

Hydroxyapatite (HAp) has been successfully coated on etched titanium substrates by hydrothermal method using solutions of Ca(NO3)2.4H2O, NH4H2PO4 at 200 oC for 12 h. Results obtained from measurements on the modern physical methods of FE-SEM and XRD showedhat the structure of HAp has a regular hexagonal morphology belonging to the space group P63/m. The degree of HAp nucleation and nucleation development on the un-etched titanium plates was lower than that on the etched titanium plates. In vitro bioactivity of HAp-coated titanium testing using SBF solution showed prospective results. Keywords: Hydroxyapatite (HAp), Hydrothermal method, etched, titanium.

This paper reported the impact of pH on the structure, morphology, and the green upconversion (UC) emission of Er/Yb/Mo tri-doped hydroxyapatite (HA) synthesized through hydrothermal method. X-ray diffraction confirmed that the pH of the solution strongly influenced the phase composition of the phosphors, and HA single phase was obtained at a high pH value. Transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) images of the phosphor exhibited rod-like morphology, and their length increased with increased of the pH values. Under laser-diode excitation wavelength of 975 nm, the phosphor showed typical upconversion emission bands of the ion: strong green emission bands around 510-535/540-560 nm and weak red emission bands around 630-680 nm. The green and red emission intensity as a function of pH reached its maximum value at pH8. Finally, the emission intensity of

This article reports on the synthesis procedure of ZnO nanoparticles/nanofibers structure by electrospinning method using Zinc acetate and polyvinylpyrrolidone (PVP) surfactant as reagents and evaluates their luminescent properties. The microstructure of ZnO nanoparticles/nanofibers was observed by FE-SEM. The phase formation of ZnO nanoparticles/nanofibers was studied by XRD. ZnO nanoparticles/nanofibers structure shows strong luminescence centering at 660 nm, which has potential applications in solid-state lighting.

In this work, a CeO 2 nanorod (NR)-based electrochemical DNA sensor was developed to identify Salmonella that causes food-borne infections. CeO 2 NRs were synthesized without templates via a simple and unexpensive hydrothermal approach at 170 °C for 12 h by using CeO(NO 3 ) 3 ·6H 2 O as a Ce source. The DNA probe was immobilized onto the CeO 2 NR-modified electrode through covalent attachment. The characteristics of the hybridized DNA were analyzed through electrochemical impedance spectroscopy (EIS) with [Fe(CN) 6 ] 3−/4− as a redox probe. Experimental results showed that electron transfer resistance (R et ) increased after the DNA probe was attached to the electrode surface and increased further after the DNA probe hybridized with its complementary sequence. A linear response of R et to the target DNA concentration was found from 0.01 μM to 2 μM. The detection limit and sensitivity of the DNA sensor were 0.01 μM and 3362.1 Ω μM −1 cm −2 , respectively. Various parameters, such as pH value, ionic strength, DNA probe concentration, and hybridization time, influencing DNA sensor responses were also investigated.

In this work, we evaluated the effects of different antibody immobilization strategies on the response of a CeO2-nanowires (NWs)-based immunosensor for Vibrio cholerae O1 detection. Accordingly, the changes in the electron-transfer resistance (R et ) from before to after cells bind to an antibody-modified electrode prepared by using three different methods of antibody immobilization were determined. The values were 16.2%, 8.3%, and 6.65% for the method that utilized protein A, antibodies activated by 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC)/N-hydroxysuccinimide (NHS), and absorption, respectively. Cyclic voltammetry confirmed that the change in the current was highest for the immunosensors prepared using protein A (11%), followed by those prepared with EDC/NHS-activated antibodies (9%), and finally, those prepared through absorption (7.5%). The order of the antibody immobilization strategies in terms of resulting immunosensor detection limit and sensitivity was as follows order: absorption (3.2 × 103 CFU/mL; 45.1 Ω/CFU·mL−1) < EDC/NHS-activated antibody (1.0 × 103 CFU/mL; 50.6 Ω/CFU·mL−1) < protein A (1.0 × 102 CFU/mL; 65.8 Ω/CFU·mL−1). Thus, we confirmed that the protein A - mediated method showed significantly high cell binding efficiencies compared to the random immobilization method.