Yousef Mohammed Alanazi

The synthesis of sustainable and promising biomaterials for biomedical applications has recently gained increasing importance. In this study, a hybrid hydrogel was synthesized from empty palm date bunches through the blending of natural (carboxymethyl cellulose) and synthetic polymers (polyvinyl alcohol, polyvinylpyrrolidone) using both traditional and microwave-assisted methods. The aim was to investigate the ability of the hydrogel to immobilize and control the release of bovine serum albumin (BSA), a model protein widely used in pharmaceutical biotechnology. The effect of key parameters such as pH, temperature and hydrogel dosage on protein immobilization was investigated. Optimal results were observed at a pH of 7.4, a temperature of 37 °C and a dosage of 2 g/L—such conditions are very close to the human physiological environment. Kinetic and isotherm models indicated that the immobilization process adhered to pseudo-second-order kinetics and was well-fitted to the Langmuir isotherm. This implied a monolayer adsorption mechanism on a comparatively homogeneous surface. The release studies demonstrated a time-dependent and diffusion-controlled trend, with BSA attaining equilibrium release at 150 min. Overall, the results underline the potential of the microwave-synthesized plant-based hydrogel as a promising material for controlled drug delivery and other biomedical applications due to its efficiency and sustainability.

This study investigates the transformation of waste cooking oils into amides to serve as corrosion inhibitors for carbon steel in hydrochloric acid environments. Fourier-transformed infrared spectroscopy (FTIR) and proton nuclear magnetic resonance (¹HNMR) methods were then used to analyze the presence of amides inhibitors. The application of inhibitor to carbon steel prior to immersion in hydrochloric acid was effective in delaying the corrosion rate and increasing resistance towards corrosion by forming a protective barrier on the surface. The effects of temperature and inhibitory ratio on the efficacy of corrosion inhibition under various conditions were also determined. The maximum effectiveness of 88.5% was attained at 298 K with an inhibitor ratio of 2000 ppm. Kinetic analysis at different temperatures was also carried out to determine the response mechanisms of inhibitors. According to the inhibitor thermal adsorption isotherm, the steel surface is complexed based on the Langmuir adsorption isotherm. Inhibition and corrosion investigations were also performed by using electrochemical impedance spectroscopy (EIS). Scanning electron microscopy, energy dispersive X-ray spectroscopy and atomic force microscopy study established the existence of a protective adsorbed film of inhibitor molecules over the metal surface. This study contributes to the advancement of science and engineering pertaining to improved corrosion resistance under acidic conditions and the mitigation of used cooking oils.