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The presence of pharmaceuticals as the emerging contaminates needs novel approaches and new materials to be remediated. This study aimed to develop and apply MWCNTs reinforced with glutaraldehyde cross-linked poly (vinyl alcohol)/chitosan nanocomposite (MWCNTs/CS-PVA/GA NC) for removal of tetracycline (TC) as a model of antibiotics from aqueous solutions. The successful synthesis of NC was supported by techniques of SEM, XRD, TGA, FTIR, and EDX. The prepared NC was then utilized for TC adsorption under the main effective parameters of TC concentration (25-125 mg/L), sonication time (0-8 min), NC dose (1-130 mg), and tempearure (5-45 °C). The process behavior was comparably explored with different methods of central composite design (CCD), artificial neural networks (ANN), and general regression neural network (GRNN). The results showed that under the optimum settings presented by desirability function (DA), in which the respective values for the factors were 125 mg/L, 6.8 min, 130 mg, and 45 °C, the efficiency and adsorption capacity of NC is supposed to be 99.07% and ∼525 mg/g, respectively. From the models studied, although all were able to express the process with satisfactory accuracy, ANN provided the best accuracy and reliability owning to the highest R 2 (0.999) and lowest RMSE, ADD, MAE. The kinetics, isotherms, and thermodynamic studies showed that the process is fast (over 4.5 min), chemisorption, heterogeneous with multilayer nature, spontaneous, feasible, and endothermic. In addition, the as prepared NC could be recycled for five times without significant fail in its performance. All in all, the developed MWCNTs/CS-PVA/GA NC can be considered as a promising candidate in dealing with aqueous solutions' pollution with antibiotic., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Amyloid fibrils were produced in a solution of bovine serum albumin (BSA) in buffer solution in the presence of fructose. The solution was incubated for 20 weeks in the dark. We used glycation induced bovine serum albumin in which fibrilogenesis (nano fibrils) followed by using fluorescence (Thioflavin T), Dynamic Light Scattering (DLS) and Transmission Electron Microscopy (TEM) to achieve the size and morphology of fibrils. A novel electrochemical biosensor for the detection of hydrogen peroxide was developed based on immobilizing poly (alizarin yellow R) and amyloid nano-fibrils on glassy carbon electrode (PAYR/AMLNFibs/GCE). The electrocatalytic response of the biosensor was proportional to the hydrogen peroxide concentration in the range of 1 μM to 2.2 mM with a limit of detection and sensitivity of 290 nM and 0.024 μA/μM, respectively. The modified electrode demonstrated many advantages such as high sensitivity, low detection of limit and excellent catalytic activity., (Copyright © 2018 Elsevier B.V. All rights reserved.)