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A cellulose polymer functionalized with an amine chelating agent was designed and synthesized in a three-step process that involved oxidizing cellulose powder into dialdehyde cellulose, reacting cellulose dialdehyde with phenyl biguanide to create an imine linkage between the two reactants, and reducing the imine linkage to an amine. The cellulose amine polymer was cross-linked with glycerol digycidyl ether and evaluated as an adsorbent of toxic metal ions from wastewater. The adsorption efficiency of the cross-linked cellulose amine polymer toward Pb(II) and Cu(II) was evaluated as a function of the adsorbent dose, pH, time, temperature, and initial ion concentration. The cross-linked cellulose amine polymer showed an excellent efficiency toward over 15 metal ions present in a real sample of sewage. Thermodynamic analysis showed a spontaneous adsorption of metal ions on the polymer at room temperature. Monte Carlo and Molecular Dynamic simulations showed that the Cu(II) and Pb(II) ions adsorbed onto the cellulose amine polymer surface in a considerable amount, which agreed with the experimental and thermodynamic data. The negative free energy value confirmed the spontaneity of the adsorption process. As such, cross-linked cellulose amine polymers could be a promising alternative to current commercial adsorbents.

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The development of efficacious and safe drugs for the treatment of neurological diseases related to glutamate toxicity has been a focus in neuropharmacological research. Specifically, discovering antagonists to modulate the activity and kinetics of AMPA receptors, which are the fastest ligand-gated ion channels involved in excitatory neurotransmission in response to glutamate. Thus, the current study investigated novel curcumin derivatives on the biophysical properties of AMPA receptors, specifically on the homomeric GluA2 and the heteromeric GluA2/A3 subunits and assessed for inhibitory actions. The biophysical parameter (i.e., desensitization, deactivation, and peak currents) were measured by using whole-cell patch clamp electrophysiology with and without the administration of the derivatives onto HEK293 cells. CR-NN, CR-NNPh, CR-MeNH, and CR-NO of the tested derivatives showed inhibition on all AMPA receptors up to 6 folds. Moreover, the inhibitory derivatives also increased desensitization and deactivation, which further intensifies the compounds’ neuroprotective effects. However, CR-PhCl, CR-PhF, and CR-PhBr did not show any significant changes on the peak current, deactivation or desensitization rates. By comparison to other discovered and widely used antagonist, the prepared curcumin derivatives are not selective to a specific AMPA subunit, instead implement its effect in the same way between all types of AMPA receptors. Additionally, the obtained results provide derivatives that not only noncompetitively inhibit AMPARs but also decrease its biophysical kinetics, specifically desensitization and deactivation rates. Hence, to potentially serve as a new AMPAR inhibitor with therapeutic potential, the current study provides compounds that are non-selective and non-competitive antagonist, which also effect the desensitization and deactivation rates of the receptor.

Developing a new effective anticancer agent becomes an urgent need to overcome of current drug-resistance. In this study we demonstrated that curcumin with heterocyclic moiety can function as an anticancer agent in a human. A new series of curcumin-based benzodiazepines, diazepines and diazoles were prepared using a simple one pot process. The process involved a condensation reaction of curcumin with various 1,2 diamino compounds and hydrazine. The structures of the prepared heterocycles were identified by the spectroscopic methods FT-IR, 1H NMR, and 13C NMR. The in vitro anticancer activities of the synthesized curcumin-based heterocycles against HeLa cancer cells were evaluated by the 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT) assay. The viability of HeLa cells was reduced in the range of 4.48- 14.57% within the studied concentrations. Curcumin-based diazepine 6 showed the highest cytotoxic effect on the HeLa cells at all concentrations. it reduced the viability of the tested HeLa cells in range of 4.48 % for the 400 μg /ml concentration to 4.95% for the 12.5 μg /ml concentration. Moreover, heterocyclic 6 showed the highest cytotoxic and cytostatic effect among the tested heterocyclics against Hela cells. It exhibited IC50 and a cytostatic effect of of 0.4572 and 0.08515 µg/ml, respectively at a nontoxic level, as the control L6 cells showed cytotoxic and cytostatic effect with IC50 values of 22.47 and 1.977 µg/ml, respectively. This study revealed that, the prepared curcumin-based compounds exhibit a promising anticancer activity against HeLa cancer cells at a nontoxic concentration.