Nasrullah Shah

Novel, eco-friendly, and biocompatible bi-biopolymer magnetic composite beads were synthesized by integrating sodium alginate and agar with iron oxide (Fe₃O₄) and green tea-mediated manganese oxide (MnO) nanoparticles. The bi-biopolymer magnetic composite beads prepared with varying contents (10.15-30%) of MnO nanoparticles were systematically characterized using FTIR Spectroscopy, SEM, EDX, XRD, TGA, BET analysis, and electrical conductivity analyses, confirming uniform nanoparticle dispersion and strong polymer matrix-nanoparticle interactions. Among the synthesized formulations, 30%@SAMN (sodium alginate-agar magnetic nanocomposite beads) exhibited superior adsorption performance, achieving approximately 99% methylene blue removal at pH 9 using a 0.01 g adsorbent dose with equilibrium reached within 10 min. The enhanced adsorption efficiency was attributed to increased surface roughness, higher porosity, and abundant active adsorption sites resulting from higher MnO nanoparticle incorporation and synergistic interaction with Fe₃O₄ nanoparticles. Adsorption kinetics followed the pseudo-second-order model, while equilibrium data showed excellent agreement with the Langmuir isotherm with a maximum adsorption capacity of 61.25 mg g^-1. Thermal and swelling analyses revealed enhanced crosslinking and thermal resistance with increasing MnO incorporation. The nanocomposite beads also demonstrated remarkable multifunctionality, showing strong antibacterial, antioxidant, anti-inflammatory, and antidiabetic properties along with promising hemostatic and electrical performance. Overall, the results highlight the successful development of a high-performance, thermally stable, and magnetically responsive nanocomposite with broad potential applications in environmental remediation, biomedical engineering, and advanced material systems.

Developing new materials for advanced analytical and biological applications is always a key target in the field of advanced materials. In the present study, a poly(methacrylic acid-co-acrylonitrile)-grafted-magnetic nanocrystalline cellulose composite [P(MAA-co-AN)-g-MNCC] was synthesized through a modified free-radical grafting co-polymerization method using cellulose recovered from waste paper. The synthesized composite was characterized via FTIR spectroscopy, SEM, EDX, and TGA, and its E_g, PZC, and surface area were determined. The as-synthesized P(MAA-co-AN)-g-MNCC was studied as an adsorbent for the removal of gallic acid (GA) from aqueous environments and as an antimicrobial and antioxidant agent. The influence of various experimental factors, including contact time, pH, temperature, and GA concentration, was investigated to optimize the adsorption process. The adsorption process follows pseudo-second-order kinetics and the Freundlich model with a spontaneous and exothermic nature. Similarly, the synthesized adsorbent maintained its excellent adsorption capacity when it was recycled and reused for four successive cycles in real samples. The synthesized P(MAA-co-AN)-g-MNCC also displayed good antioxidant and antibacterial activities against the tested pathogenic bacteria. The results indicated that the as-synthesized P(MAA-co-AN)-g-MNCC has the potential to be used as an effective advanced material for wastewater treatment and biomedical applications.

Introducing magnetic properties to aerogels not only opens new application areas but also enhances their performance in various applications. Herein, we report a novel 3D magnetic agar nanocomposite aerogel (3D-MANCA) with outstanding characteristics such as high porosity, magnetic property, rapid swelling behavior, and a unique stimuli-driven electrical conductivity. Agar and nanocellulose mixture were selected as the matrix material, while magnetic Fe ₃ O ₄ nanoparticles, CuO nanoparticles, and graphene nanopowder were incorporated as functional additives. 3D-MANCA obtained after a uni-directional freeze casting process exhibited a highly-ordered microporosity. It showed excellent magnetic properties and methylene-blue adsorption capability and a great performance as humidity sensor.

Citation of the publication (our own previous work), Yaseen, M

Water bodies face severe pollution from industrial operations and other human activities, endangering biotic life worldwide. Nitrate and phosphate contamination poses a significant challenge globally. This study focuses on developing an efficient adsorbent, derived from Parthenium hysterophorus (P. hysterophorus), for nitrate and phosphate removal from water. Biochar, termed P. hysterophorus stem biochar (SBC), was prepared at 650℃ and further coated with iron, creating iron-coated stem biochar (ICSBC), to enhance adsorption potential. SEM, TEM, EDX, and FTIR analyses characterized raw and coated biochars. Comparative adsorption studies revealed that P. hysterophorus ICSBC exhibited high adsorption capacity (nitrate = N = 77.17 mg/g, phosphate = P = 83.93 mg/g) and removal efficiency (nitrate = 88.19%, phosphate = 95.89%). Batch experiments explored the effects of contact time, adsorbent loading, pH, and initial concentration. Kinetic and equilibrium models demonstrated that the pseudo-second-order kinetic and Langmuir isotherm models best fit the data (R ² values: N = 0.9644, P = 0.98122, N = 93.68, P = 92.97, respectively). ICSBC’s favorable attributes, including strong adsorption, low cost, and eco-friendliness, position it as an ideal adsorbent for nitrate and phosphate removal from contaminated water. Graphical abstract

Montmorillonite clay and agar are naturally occurring materials of significant importance in designing biocompatible materials tailored for applications in biotechnology and medicine. The introduction of magnetic properties has the potential to significantly boost their characteristics and expand their applications. In this study, we have successfully synthesized highly intercalated magnetic composites, incorporating magnetic iron oxide nanoparticles (MNPs), montmorillonite clay (MMT), and agar (AG), through a thermo-physicomechanical method. Three samples of MMT-AG with 2, 1.5, and 0.5% MNPs and three sample composites of MNPs-AG with 2, 1, and 0.5% MMT clay are prepared. The synthesized composites were characterized by SEM, XRD, TGA, DTA, and FTIR. SEM analysis revealed a uniform dispersion of MNPs and MMT in the composite. The XRD pattern confirmed the presence of MNPs in the composite site. The TGA and DTA results demonstrated improved thermal stability due to the MNP incorporation. FTIR spectra showed all of the constituents of agar, MNPs, and MMT clay. The swelling ratio was observed to range from 835% to 1739%. The swelling study indicated an increased hydrophobicity with the addition of MNPs to the composite. Antibacterial activities revealed a significant inhibition of Escherichia coli (E. coli) growth by ranging from 10 to 19 nm in the composite. The composite also exhibited a considerable antioxidant action, with IC50 values of 7.96, 46.55, and 57.58 μg/mL, and electrical properties just like conductors.

Recently, there has been significant interest in photocatalytic reactions involving graphitic carbon nitride (g-C₃N₄) due to its sp²-hybridized carbon and nitrogen content and it is an ideal candidate for blending with other materials to enhance performance.