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[Display omitted] • Green synthesis of ZnO NPs with biopolymer pullulan as the capping agent. • Dependence of ZnO NPs properties on the amount of zinc salt in presence of pullulan. • Feasibility of drugs degradation using green fabricated ZnO NPs. • Effect of photocatalytic parameters on drugs' degradation rate. Heterogeneous photocatalysis is one of the popular alternative treatment methods for wastewater. It utilizes semiconductor material as the catalyst and metal oxide such as zinc oxide nanoparticles (ZnO NPs), emerged as the commonly used catalyst. In this study, a series of biogenic ZnO NPs was fabricated through precipitation method with pullulan as the biomaterial. The amount of zinc salt in the presence of pullulan was varied to study its impact on the generated ZnO NPs. The results showed that without pullulan, the average particle size of ZnO NPs obtained was 110.86 nm. With 0.84 M zinc salt in 50 g/L of pullulan, the ZnO NPs average particle size significantly reduced to 58.13 nm. The surface area of all synthesized ZnO NPs ranging from 14.84 to 19.99 m2 g−1. The photocatalytic activities of all synthesized ZnO NPs were evaluated through the photodegradation of two drugs, amoxicillin (AMX) and paracetamol (PCT). Through the comparison of drugs' photodegradation with all synthesized ZnO NPs, ZnO NPs produced with 0.67 M zinc salt in 50 g/L of pullulan showed the highest degradation percentage of 85.7% and 96.8% for AMX and PCT respectively. The best photodegradation conditions for the drugs were 30 ppm drugs concentration, pH 9 (for AMX) and pH 5 (for PCT) and 50 mg catalyst dosage. Based on these results, biogenic ZnO NPs has high potential to be used in the treatment of pharmaceutical wastewater. [ABSTRACT FROM AUTHOR]

Abstract A massive release of harmful substances especially heavy metal ions and dyes to the environment has been a major concern due to many people disregards the proper protocols in the waste management. The freshwater supplies are threatened and huge discharge of pollutants result from various anthropogenic activities may pose a major threat to the living organisms and negatively affect the ecosystem stability. This article reviews the development of magnetic iron oxide nanocomposites for removal of heavy metal ions and dyes from water. The highlight will be focused on current research activities for controlled size and dispersion of magnetic iron oxide nanoparticles within solid matrices including zeolites, silica, clays, carbon, activated carbon, graphene and graphene oxide. The magnetic properties of the nanocomposites will be evaluated to determine whether they possessed sufficient magnetization for easy separation by an external magnet. The unique features of the synthesized materials will be investigated along with their application in the removal of heavy metal ions and dyes. The advantages and limitations of the magnetic nanocomposites will be highlighted to determine their adsorption ability. The effect of various parameters such as pH, contaminants concentration, adsorbent dosage, contact time and temperature will be summarized to identify the best condition for effective pollutants removal. Graphical abstract Image 1 Highlights • Synthesis, properties and application of magnetic iron oxide NCs for the adsorption of heavy metal ions and dyes. • Methods for the preparation of magnetic iron oxide NCs with control over the size, morphology and the magnetic properties. • Factors affecting the adsorption of heavy metal ions and dyes in water by magnetic iron oxide NCs. • Influence of the iron oxide loading and specific surface area of NCs on removal of heavy metal ions and dyes in water. [ABSTRACT FROM AUTHOR]

Superparamagnetic magnetite nanocomposites (Fe 3 O 4 -NCs) were successfully synthesized, which comprised of montmorillonite (MMT) as matrix support, Kappaphycus alvarezii (SW) as bio-stabilizer and Fe 3 O 4 as filler in the composites to form MMT/SW/Fe 3 O 4 -NCs. Nanocomposite with 0.5 g Fe 3 O 4 (MMT/SW/0.5Fe 3 O 4) was selected for anticancer activity study because it revealed high crystallinity, particle size of 7.2 ± 1.7 nm with majority of spherical shape, and M s = 5.85 emu/g with negligible coercivity. Drug loading and release studies were carried out using protocatechuic acid (PCA) as the model for anticancer drug, which showed 19% and 87% of PCA release in pH 7.4 and 4.8, respectively. Monolayer anticancer assay showed that PCA-loaded MMT/SW/Fe 3 O 4 (MMT/SW/Fe 3 O 4 -PCA) had selectivity towards HCT116 (colorectal cancer cell line). Although MMT/SW/Fe 3 O 4 -PCA (0.64 mg/mL) showed higher IC 50 than PCA (0.148 mg/mL) and MMT/SW/Fe 3 O 4 (0.306 mg/mL, MMT/SW/Fe 3 O 4 -PCA showed more effective killing towards tumour spheroid model generated from HCT116. The IC 50 for MMT/SW/Fe 3 O 4 -PCA, MMT/SW/Fe 3 O 4 and PCA were 0.132, 0.23 and 0.55 mg/mL, respectively. This suggests the improved penetration efficiency and drug release of MMT/SW/Fe 3 O 4 -PCA towards HCT116 spheroids. Moreover, concentration that lower than 2 mg/mL MMT/SW/Fe 3 O 4 -PCA did not result any hemolysis in human blood, which suggests them to be ideal for intravenous injection. This study highlights the potential of MMT/SW/Fe 3 O 4 -NCs as drug delivery agent. [ABSTRACT FROM AUTHOR]

In this study, a powder mixture of Zn, Fe 2 O 3 and NiO was used to produce different compositions of Ni 1− x Zn x Fe 2 O 4 ( x =0.36, 0.5 and 0.64) nanopowders. High-energy ball milling with a subsequent heat treatment method was carried out. The XRD results indicated that for the content of Zn, x =0.64 a single phase of Ni–Zn ferrite was produced after 30 h milling while for the contents of Zn, x =0.36 and 0.5, the desired ferrite was formed after sintering the 30 h-milled powders at 500 °C. The average crystallite size decreased with increase in the Zn content. A DC electrical resistivity of the Ni–Zn ferrite, however, decreased with increase in the Zn content, its value was much higher than those samples prepared by the conventional ceramic route by using ZnO instead of Zn. This is attributed to smaller grains size which were obtained by using Zn. The FT-IR results suggested two absorption bands for octahedral and tetrahedral sites in the range of 350–700 cm −1 . The VSM results revealed that by increasing the Zn content from 0.36 to 0.5, a saturation magnetization reached its maximum value; afterwards, a decrease was observed for Zn with x =0.64. Finally, magnetic permeability and dielectric permittivity were studied by using vector network analyzer to explore microwave-absorbing properties in X-band frequency. The minimum reflection loss value obtained for Ni 0.5 Zn 0.5 Fe 2 O 4 samples, about −34 dB at 9.7 GHz, making them the best candidates for high frequency applications. [ABSTRACT FROM AUTHOR]

Abstract: We have successfully developed a simple method for preparing silver nanoparticles (Ag NPs) using UV irradiation of AgNO3 in the interlamellar space of a montmorillonite (MMT) without any reducing agent or heat treatment. The properties of Ag/MMT nanocomposites were studied as a function of the UV irradiation period. UV irradiation disintegrated the Ag NPs into smaller size until a relatively stable size and size distribution were achieved. The results from UV–vis spectroscopy show that particles size of Ag NPs decrease with the increase of irradiation period. The crystalline structure of Ag NPs was determined by powder X-ray diffraction (PXRD). [Copyright &y& Elsevier]

Magnetic polymer nanocomposites are inherently multifunctional and harbor assorted physiochemical actions for applications thereof as novel drug nanocarriers. Herein, Fe 3 O 4 -nanoparticles were supported on rice straw cellulose for 5-fluorouracil carrier abbreviated as MC/5-FU for potential colorectal cancer treatments. Several analyses indicated the multifunctional properties of MC/5-FU bionanocomposites. Transmission and scanning electron microscopy study demonstrated that Fe 3 O 4 nanofillers covered the cellulose matrix. The drug release from MC/5-FU was evaluated under various pH and temperature conditions, showing the maximum release at pH 7.4 and 44.2 °C. In in vitro anticancer assay, MC/5-FU exhibited enhanced selectivity and anticancer actions against 2D monolayer and 3D tumour spheroid models colorectal cancer cells. The anticancer effects of MC/5-FU with magnetic targeting and heat induction were also examined. This easily synthesized MC/5-FU indicated the potential in application as a low-cost drug formulation for colorectal cancer treatments. • Preparation of 5-fluorouracil loaded magnetic cellulose (MC/5-FU) as a low-cost and multifunctional bionanocomposites. • The release of drug from MC/5-FU increased with increase of pH and the temperature induction. • MC/5-FU improved the selectivity and anticancer activities towards 3D tumour spheroid models colorectal cancer cells. • MC/5-FU indicated negligible toxicity to the red blood cells in hemolysis assay. • The effect of magnetic targeting and heat induction on the killing of the colorectal tumour spheroid was investigated. [ABSTRACT FROM AUTHOR]

The artificial neural network (ANN) modeling of adsorption of Pb(II) and Cu(II) was carried out for determination of the optimum values of the variables to get the maximum removal efficiency. The input variables were initial ion concentration, adsorbent dosage, and removal time, while the removal efficiency was considered as output. The performed experiments were designed into two data sets including training, and testing sets. To acquire the optimum topologies, ANN was trained by quick propagation (QP), Batch Back Propagation (BBP), Incremental Back Propagation (IBP), genetic algorithm (GA) and Levenberg-Marquardt (LM) algorithms for testing data set. The topologies were defined by the indicator of minimized root mean squared error (RMSE) for each algorithm. According to the indicator, the IBP-3-9-2 was selected as the optimized topologies for heavy metal removal, due to the minimum RMSE and maximum R-squared. [ABSTRACT FROM AUTHOR]

Abstract: We successfully prepared colloidal silver nanoparticles (Ag-NPs) using a nanosecond pulsed Nd:YAG laser, λ =532nm, with laser fluence of approximately about 0.6J/pulse, in an aqueous gelatin solution. The size and optical absorption properties of samples were studied as a function of the laser repetition rates. The results from the UV–vis spectroscopy demonstrated that the mean diameter of Ag-NPs increase with the laser repetition rate increases. The Ag-NPs have mean diameters ranging from approximately 9nm to 15nm. Compared with other preparation methods, this work is clean, rapid, and simple to use. [ABSTRACT FROM AUTHOR]

Abstract: We have investigated the spatial self-phase modulation (SSPM) phenomena in a clay suspension containing silver nanoparticles. Silver nanoparticles (Ag-NPs) were synthesized in the space of lamellar structure of montmorillonite (MMT) by using chemical reducing agent. The UV–vis spectra of the obtained Ag-NPs showed that the intensity surface plasmon resonance (SPR) peaks increase with increasing in concentration of AgNO3. The results from Ag-NPs UV–vis spectra were in good agreement with the structure studies performed by TEM. The SSPM phenomena manifestation of the non-linear optical property appeared only when MMT suspension filled with Ag-NPs as shown in the existence of far-field pattern. This property increased with the increase of Ag-NPs concentration and limited to small range. [Copyright &y& Elsevier]