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An efficient magnetic polymer-based nanomaterial was prepared in three main steps including synthesis of polyacrylonitrile (PAN), modification of PAN with melamine, and magnetization of the PAN@melamine compound by in situ construction of Fe 3 O 4 MNPs. The novel PAN@melamine/Fe 3 O 4 organometallic nanocomposite was well characterized by various techniques such as Fourier transform infrared (FT-IR) spectroscopy, energy dispersive X-ray (EDX) spectroscopy, thermogravimetric analysis (TGA), field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) pattern, and vibrating sample magnetometer (VSM) curve. Afterward, the fabricated nanocomposite was used as a heterogeneous catalyst in two multicomponent reactions (MCRs) for the synthesis of biologically active dihydropyrano[2,3-c]pyrazole and 2-amino-3-cyano 4H-pyran derivatives. The corresponding products were obtained in excellent yields without a complicated work-up process. Besides, the prepared nanocatalyst could be recycled and reused at least five consecutive runs in both MCRs without a considerable decline in its catalytic activity.

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As an efficient class of hydrogel-based therapeutic drug delivery systems, deoxyribonucleic acid (DNA) hydrogels (particularly DNA nanogels) have attracted massive attention in recent five years. The main contributor to this...

The Arabic gum-grafted-hydrolyzed polyacrylonitrile/ZnFe 2 O 4 (AG-g-HPAN@ZnFe 2 O 4 ) as organic/inorganic adsorbent was obtained in three steps using grafted PAN onto Arabic gum in the presence of ZnFe 2 O 4 magnetic nanoparticles and then hydrolysis by alkaline solution. Fourier transform infrared (FT-IR), energy-dispersive X-ray analysis (EDX), field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), vibrating sample magnetometer (VSM), and the Brunauer−Emmett−Teller (BET) analysis analyses were used to characterize the chemical, morphological, thermal, magnetic, and textural properties of the hydrogel nanocomposite. The obtained result demonstrated that the AG-g-HPAN@ZnFe 2 O 4 adsorbent showed acceptable thermal stability with 58% char yields and superparamagnetic property with magnetic saturation (Ms) of 24 emu g −1 . The XRD pattern showed that the semicrystalline structure with the presence of ZnFe 2 O 4 has distinct peaks which displayed that the addition of zinc ferrite nanospheres to amorphous AG-g-HPAN increased its crystallinity. The AG-g-HPAN@ZnFe 2 O 4 surface morphology exhibits uniform dispersion of zinc ferrite nanospheres throughout the smooth surface of the hydrogel matrix, and its BET surface area was measured at 6.86 m 2 /g, which was higher than that of AG-g-HPAN as a result of zinc ferrite nanosphere incorporation. The adsorption effectiveness of AG-g-HPAN@ZnFe 2 O 4 for eliminating a quinolone antibiotic (levofloxacin) from aqueous solutions was investigated. The effectiveness of adsorption was assessed under several experimental conditions, including solution pH (2−10), adsorbent dose (0.0015−0.02 g) contact duration (10−60 min), and initial concentration (50−500 mg/L). The maximum adsorption capacity (Q max ) of the produced adsorbent for levofloxacin was found to be 1428.57 mg/g (at 298 k), and the experimental adsorption data were well explained by the Freundlich isotherm model. The pseudo-second-order model satisfactorily described the adsorption kinetic data. The levofloxacin was mostly adsorbed onto the AG-g-HPAN@ZnFe 2 O 4 adsorbent via electrostatic contact and hydrogen bonding. Adsorption−desorption studies demonstrated that the adsorbent could be efficiently recovered and reused after four consecutive runs with no significant loss in adsorption performance.