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• New hydroxylammonium - based ILs. • Structure confirmed by FTIR and 1D NMR spectroscopy. • Correlation between chemical structure and ion conductivity. In the research work, new protic ionic liquids (Pr - ILs) were synthesized by an acid - base neutralization reaction. The influence of IL chemical structure (i.e. anion and cation nature) on the thermal behavior, viscosity and ionic conductivity was evaluated. To confirm the chemical structure of synthesized Pr - ILs, nuclear magnetic resonance (1H and 19F) and Fourier transform infrared spectroscopy analyses were performed. Thermal analysis demonstrated that the influence of anion nature on the IL thermal stability was more pronounced than that of cation. The ionic liquids with trifluoromethanesulfonate anion showed the highest thermal stability (T deg ∼ 410–420 °C) as compared with other studied anions (i.e. phosphate and acetate anions). The trifluoromethanesulfonate - based Pr - ILs also demonstrated high ionic conductivity – between ∼58 and ∼64 mS·cm−1 at 150 °C and non - humid conditions. Despite the fact that phosphate - based Pr - ILs were more thermally stable (T deg ∼ 250–280 °C) than acetate - based ones (T deg ∼ 215 °C), acetate - based Pr - ILs revealed a higher ionic conductivity (∼15–19 mS·cm−1 at 80 °C) than phosphate - based Pr - ILs (∼0.2–1 and ∼0.4–2 mS·cm−1 at 80 and 120 °C, respectively). The obtained results confirm that the synthesized Pr - ILs are promising candidates for using them in electrochemical applications, namely, electrodialysis and fuel cells. [ABSTRACT FROM AUTHOR]

An ultrasensitive novel electrochemical nano-biosensor for rapid detection of insulin antibodies against diabetes antigens was developed in this research. The presence of insulin antibodies has been demonstrated to be a strong predictor for the development of type 1 diabetes in individuals who do not have diabetes but are genetically predisposed. The proposed nano-biosensor fabrication process was based on the optimized sequential electropolymerization of polyaniline and electrodeposition of gold nanoparticles on the surface of the functionalized gold electrode. The morphological and chemical characterization of the modified electrode was studied by field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), and micro Raman spectroscopy. Moreover, the role of each component in the modification of the electrode was studied by electrochemical methods systematically. After immobilizing insulin antigen and blocking with bovine serum albumin, the nano-biosensor was used for determining different concentrations of insulin antibody under the optimal conditions. This nano-biosensor could respond to insulin antibody with a linear calibration range from 0.001 ng ml−1 to 1000 ng ml−1 with the detection limit of 0.017 pg ml−1 and 0.034 pg ml−1 and selectivity of 18.544 μA ng−1 ml.cm−2 and 31.808 μA ng−1 ml.cm−2 via differential pulse voltammetry and square wave voltammetry, respectively. This novel nano-biosensor exhibited a short response time, high sensitivity, and good reproducibility. It was successfully used in determining the insulin antibody in human samples with a standard error of less than 0.178. Therefore, the nano-biosensor has the potential for the application of early detection of type 1 diabetes. To our best knowledge, label-free electrochemical detection of insulin antibody based on immunosensor is developed for the first time. [Display omitted] • The label-free electrochemical immunosensor for rapid detection of insulin antibody related to type 1 diabetes. • The controllable electrochemical procedure for fabrication of nano-biosensor substrate to improve accuracy, and stability. • The parameters optimization: electrodeposition cycles, immobilization concentration and time of antigen, and response time. [ABSTRACT FROM AUTHOR]

In this study, carbon nanofibers (CNFs) assisted chitosan (Cs) was utilized to surface modification of poly(ether sulphone) (PES) nanofiltration membranes. The effect of CNFs-co-Cs nanocomposite layer on physical/chemical properties and separation performance of prepared membranes was investigated. The ability of membranes in heavy metal ions removal from water was studied. Scanning electron microscopy (SEM), Scanning optical microscopy (SOM), Fourier transform infrared spectroscopy (FTIR) and 3D surface images were employed for the membranes characterization. Moreover membrane porosity, mean pore size, water content, water contact angle, flux, salt rejection and tensile strength of fabricated membranes measured. The FTIR analysis verified formation of CNFs-co-Cs layer on the membrane surface. SOM images revealed relatively uniform surface for the prepared membrane. Introducing of CNFs-co-Cs on the PES substrate led to decline of water contact angle from 62.66° to 43.86° sharply. Modified membranes showed higher porosity and water content than virgin PES membrane. The Na 2 SO 4 rejection was measured >66% for PES membrane while it was >82% for PES/CNFs-co-Cs membrane containing of 0.5 wt% CNFs. Pure water flux also enhanced from 4.25 (L/m2.h) for virgin PES membrane up to 13.58 (L/m2.h) for the surface modified membranes. Mechanical tensile strength was also increased considerably for the PES/CNFs-co-Cs membrane containing of 0.5 wt% CNFs that were 3.5 times more than the tensile strength for PES membrane. The Cu, Cr and Pb rejections measured 97.86%, 98.40% and 96.54% for the PES/CNFs-co-Cs membrane with 0.5 wt % CNFs while they were 45.3%, 48.46% and 38.02 for PES substrate respectively. [Display omitted] • PES/CNFs-co-Cs nanofiltration membrane fabricated through intra-networking. • PWF measured 4.25 and 13.58 (L/m 2 h) for PES and [PES/CNFs-co-Cs] membranes. • Na 2 SO4 rejection was >66% and >88% for virgin and surface modified membranes. • [PES/CNFs-co-Cs] membrane showed high ability in Cu, Cr, Pb removal from water. • Outstanding tensile strength obtained for CNFs-co-Cs coated PES based NF membrane. [ABSTRACT FROM AUTHOR]