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Arsenic contaminated water is an environmental issue due to their toxicity. Acute arsenic poisoning has claimed the lives of many and causes adverse health risk to millions of people in several countries such as Bangladesh, India, and China. Effective removal of this contaminant can be obtained by adsorbing them onto low-cost adsorbents. In this study, hydrogel-biochar composite (HBC-RH) was successfully synthesized by embedding rice husk biochar into poly(acrylamide) hydrogel with N.N’-methylenebisacrylamide (MBA) as crosslinker. The synthesized HBC-RHs were characterized and utilized for the removal of arsenic from wastewater. The experimental parameters that influence the sorption process were investigated. The results obtained revealed that the effective removal of arsenic was found to be dependent on solution pH, sorbent dosage, initial contaminant concentration, and contact time. HBC-RH maximum monolayer sorption capacity for arsenic was 28.32 mg g −1 and the experimental data suggested that the arsenic sorption was best fitted by pseudo-second-order kinetic mode. Above all, HBC-RH can easily be separated from aqueous solution after accomplishing its mission, avoiding separation complications faced by powder adsorbents in aqueous media.

Graft copolymerization of acrylonitrile onto sago starch was carried out by a free radical initiating process in which the ceric ion (Ce 4+ ) was used as an initiator. The reaction conditions significantly influence the graft copolymerization. The percentage of grafting, grafting efficiency and rate of grafting were all dependent on the concentration of ceric ammonium nitrate (CAN), acrylonitrile (AN), sago starch (AGU, anhydro glucose unit), mineral acid (H 2 SO 4 ) and the reaction temperature and period. The optimum yield was obtained when the concentrations of CAN, AN, AGU and H 2 SO 4 were used at 9.61×10 −3 , 0.653, 0.152 and 0.187 mol L −1 , respectively. The optimum temperature and reaction period were 50°C and 90 min, respectively. The rate of graft copolymerization was examined using the experimental results and the reaction mechanism. The polya1crylonitrile grafted sago starch was characterized by using FT-IR spectroscopy, DSC and SEM analysis.

Fong Yen Woo,1 Mahiran Basri,1,2 Hamid Reza Fard Masoumi,1 Mansor B Ahmad,1 Maznah Ismail2 1Department of Chemistry, Faculty of Science, 2Laboratory of Molecular Biomedicine, Institute of Bioscience, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Abstract: Galantamine hydrobromide (GH) is an effective drug for Alzheimer’s disease. Itis currently delivered via the oral route, and this might cause nausea, vomiting, and gastrointestinal disturbance. In the present work, GH was formulated in a gel-type drug reservoir and then optimized by using response surface methodology (RSM) based on central composite design. This optimization study involved three independent variables (carbopol amount, triethanolamine amount, and GH amount) and two dependent variables (cumulative drug release amount at 8hours and the permeation flux of drug). Two models using expert design software were fitted into a quadratic polynomial model. The optimized gel was formulated with 0.89% w/w carbopol, 1.16% w/w triethanolamine, and 4.19% w/w GH. Optimization analysis revealed that the proposed formulation has the predicted cumulative drug release amount at 8 hours of 17.80mg·cm-2 and the predicted permeation flux of 2.27mg·cm-2/h. These predicted values have good agreement to actual cumulative drug release amount at 8hours (16.93±0.08mg·cm-2) and actual permeation flux (2.32±0.02mg·cm-2/h). This optimized reservoir formulation was then fabricated in the transdermal patch system. This patch system has moderate pH, high drug content, and controlled drug-release pattern. Thus, this patch system has the potential to be used as the drug carrier for the treatment of Alzheimer’s disease. Keywords: response surface methodology, central composite design, analysis of variance, Franz diffusion cell

Majid Darroudi1,2, Mansor Bin Ahmad3, Reza Zamiri4, AK Zak5, Abdul Halim Abdullah1,3, Nor Azowa Ibrahim31Advanced Materials and Nanotechnology Laboratory, Institute of Advanced Technology (ITMA), Universiti Putra Malaysia, Selangor, Malaysia; 2Department of Chemistry, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran; 3Department of Chemistry, 4Department of Physics, Faculty of Science, Universiti Putra Malaysia, Selangor, Malaysia; 5Low Dimensional Materials Research Center, Department of Physics, Faculty of Science, University of Malaya, Kuala Lumpur, MalaysiaAbstract: The application of “green” chemistry rules to nanoscience and nanotechnology is very important in the preparation of various nanomaterials. In this work, we successfully developed an eco-friendly chemistry method for preparing silver nanoparticles (Ag-NPs) in natural polymeric media. The colloidal Ag-NPs were synthesized in an aqueous solution using silver nitrate, gelatin, and glucose as a silver precursor, stabilizer, and reducing agent, respectively. The properties of synthesized colloidal Ag-NPs were studied at different reaction times. The ultraviolet-visible (UV-vis) spectra were in excellent agreement with the obtained nanostructure studies performed by transmission electron microscopy (TEM) and their size distributions. The prepared samples were also characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). The use of eco-friendly reagents, such as gelatin and glucose, provides green and economic attributes to this work.Keywords: silver nanoparticles, gelatin, green chemistry, time-dependent effect, ultraviolet-visible spectra

Kamyar Shameli1, Mansor Bin Ahmad1, Mohsen Zargar2, Wan Md Zin Wan Yunus1, Abdolhossein Rustaiyan3, Nor Azowa Ibrahim11Department of Chemistry, Faculty of Science, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 2Department of Biology, Faculty of Science, Islamic Azad University, Qom Branch, Qom, Iran; 3Department of Chemistry, Science and Research Branch, Islamic Azad University, Tehran, IranAbstract: Silver nanoparticles (Ag NPs) were synthesized by the chemical reducing method in the external and interlamellar space of montmorillonite (MMT) as a solid support at room temperature. AgNO3 and NaBH4 were used as a silver precursor and reducing agent, respectively. The most favorable experimental conditions for synthesizing Ag NPs in the MMT are described in terms of the initial concentration of AgNO3. The interlamellar space limits changed little (d-spacing = 1.24–1.47 nm); therefore, Ag NPs formed on the MMT suspension with d-average = 4.19–8.53 nm diameter. The Ag/MMT nanocomposites (NCs), formed from AgNO3/MMT suspension, were characterizations with different instruments, for example UV-visible, PXRD, TEM, SEM, EDXRF, FT-IR, and ICP-OES analyzer. The antibacterial activity of different sizes of Ag NPs in MMT were investigated against Gram-positive, ie, Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) and Gram-negative bacteria, ie, Escherichia coli, Escherichia coli O157:H7, and Klebsiella pneumoniae, by the disk diffusion method using Mueller-Hinton agar (MHA). The smaller Ag NPs were found to have significantly higher antibacterial activity. These results showed that Ag NPs can be used as effective growth inhibitors in different biological systems, making them applicable to medical applications.Keywords: silver nanoparticles, nanoparticles, montmorillonite, antibacterial activity, Mueller-Hinton agar&nbsp