Facile Fabrication of Polysaccharide Nanocomposites Using Ionic Gelation Method

Polysaccharide-based nanomaterials with significant biocompatibility and physiochemical features have been widely analyzed in modern biomedical nanotechnology. Chitosan-coating is an advantageous procedure to provide several pharmacological characteristics of chitosan on the reinforcement. Here, we fabricated polysaccharide nanocomposites using the facile ionic gelation method and sodium tripolyphosphate (TPP) cross-linker. The polysaccharide nanocomposites comprised natural cellulose and chitosan as reinforcement and coating agents, respectively. From the image of the scanning electron microscope, the nanocomposites indicated almost spherical dimensions with sizes below 60 nm. Results from X-ray powder diffraction and Fourier-transform infrared spectroscopy showed multifunctional properties of the nanocomposites related to both cellulose and chitosan. Therefore, the ionic gelation method is potentially appropriate to synthesize the polysaccharide nanocomposites for medically-related applications.

Green Route for the Fabrication of ZnO Nanoparticles and Potential Functionalization with Chitosan Using Cross-linkers: A Review

Zinc oxide is of significant importance for many industries due to its versatile properties, which have been enhanced with the production of this material in the nanoscale. Recent interest in the preparation of metal oxide nanoparticles using biological approaches has been reported in the literature. This technique known as “green synthesis” is an environmentally benign process than conventional methods like physical and chemical synthesis methods. Zinc oxide nanoparticles (ZnO-NPs) have been successfully obtained by green synthesis using different biological substrates like chitosan. Chitosan is biocompatible, biodegradable polymer having exclusive physical and chemical properties. Chitosan/metal oxide nanocomposite is a promising nanomaterial with enhanced properties for multiple functionalities. Therefore, this review discusses favorable approach in the formation of cross-linked Chitosan/ZnO nanocomposites attracting significant attention in various fields such biomedical due to their unique biodegradable, biocompatible, non-toxic nature. The use of biological sources, fabrication of green synthesized ZnO nanoparticles and its applications is briefly discussed. Overall, this review is a comprehensive study for the synthesis of ZnO-NPs using biological sources counting on their features and applications.

Biosynthesis of Silver Nanoparticles Using Juglans Regia Green Husk (Walnut) Water Extract and evaluation Antibacterial activity

Biosynthesis of Ag-NPs at room temperature by using Juglans regia (J. regia) green husk extract which acts as reductant and stabilizer, simultaneously. The Ag/J. regia were characterized by using UV–visible, zeta potential, TEM, and AFM. Formation of Ag/ J. regia was determined by UV–vis spectroscopy, where absorption maxima surface plasmon at 400-460 nm. The zeta potential analysis indicated that J. regia green husk extract was negative and increasing in Ag/ J. regia. TEM images show the mean particle size was 31.37 nm with the standard deviation of 7.1 nm, where confirm by AFM measurements. The XRD study indicates the crystalline nature of the Ag-NPs. The antibacterial activity of Ag-NPs was investigated against Gram-positive and Gram-negative bacteria by the disc diffusion method were found to have high antibacterial activity. These results show that Ag-NPs can be useful in different biologic research and biomedical applications.

Green Synthesis of Silver Nanoparticles Using Hibiscus sabdariffa Leaves Extract

The present paper reports the synthesis of silver nanoparticles (Ag-NPs) by a green method using Hibiscus sabdariffa (H. sabdariffa) leaves extract as reductant and stabilizer. The synthesized Ag-NPs were characterized by ultraviolet-visible (UV-vis) spectroscopy, transmission electron microscopy (TEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). UV-vis spectrum of synthesized Ag-NPs showed a peak at 378 nm. TEM analysis revealed that the particles were spherical and irregular in shape and has average size around 56.52 nm. This structure and size of particles were confirmed by AFM analysis. The UV-vis and FTIR spectrum provides evidence of the presence of caffeic acid component as a representative biomolecule in stabilising the nanoparticles based on previous studies. Hence, this study advocates that H. sabdariffa have potential for synthesizing nanoparticles.

Gamma Irradiation-Assisted Synthesis of Silver Nanoparticle and Their Antimicrobial Applications: A Review

This review presents an introduction to the synthesis of silver nanoparticles (Ag-NPs) by gamma irradiation method. This method offers some benefits over the conventional methods because it provides fully reduced and highly pure nanoparticles free from by-products or chemical reducing agents, and is capable of controlling the particle size and structure. The nucleation and growth mechanism of metallic nanoparticles are also discussed. The competition between nucleation and growth process in the formation of nanoparticles can determine the size of nanoparticles which is influenced by certain parameters such as the choice of solvents and stabilizer, the precursor to stabilizer ratio, pH during synthesis, and absorbed dose. The present review, summarizes the gamma irradiation synthesis of Ag-NPs procedure, advantages, applications and their antibacterial properties.

Silver Nanoparticles Loaded Activated Carbon Synthesis Using Clitorea Ternatea Extract for Crystal Violet Dye Removal

Dyes are coloured compound which are widely used in textile, painting, rubber, cosmetics, plastics and leather industry to colour their products. However, the irresponsibility of certain manufacturer results in producing dye waste and channel it to water resources had become one of the biggest challenges in water pollution. In this study, an effective solid adsorbent derived from sustainable sources for adsorption capacity study was produced which is silver nanoparticles loaded activated carbon (Ag NPs – AC) to remove crystal violet (CV) dye. Adsorption process are cost – effective, simple and flexible with various dye pollutants. Silver nanoparticles (Ag NPs) was synthesized from Clitorea Ternatea flower extract that utilizes functions as stabilizing agents for silver nitrate (AgNO3) to promotes environmental friendly with no toxic chemicals produced and loaded in activated carbon (AC). Characterization of Ag NPs was analysed using UV-Visible which correspond to peak at 408 nm and XRD analysis. Four peaks values for silver at 2θ of 38.19°, 44.43°, 64.57°, 77.43° and average crystallite size of Ag NPs and Ag NPs – AC were calculated to be 16.11 nm and 36.13 nm respectively that were obtained from XRD pattern. The adsorption capacity of Ag NPs – AC was analysed and the optimum conditions were determined using different parameters which are the Ag NPs - AC ratio (1.0 g), contact time (240 min), adsorbent dosage (30 mg) and pH of CV dye (10). The highest percentage removal of CV dye using Ag NPs – AC was recorded up to 97% at 240 min with 30 mg dosage. Ag NPs – AC as adsorbent is a promising advanced materials in removing water pollutants with viable conditions and can applied in the wastewater treatment industry.

Short Review: Phytofabrication of Zinc Oxide Nanoparticles for Anticancer Applications

Zinc oxide nanoparticles (ZnO NPs) are one of the most well-known materials in the field of nanotechnology. Adopting a more environmentally friendly synthesis methods of ZnO NPs have been the focus in the last few decades. Of all green synthesis methods of ZnO NPs, fabrication with the help of plant extracts has been the most popular due to its many benefits. The use of phytofabricated ZnO NPs in anticancer studies has been conducted increasingly over the last decade because of its high inhibition activity against various types of cancerous cells. This short review article will present the current update on the phytofabrication of ZnO NPs in recent years and discuss on their cytotoxicity mechanism against cancer cells.

Synthesis and Properties of Chitosan Nanoparticles CrossLinked with Tripolyphosphate

Chitosan nanoparticles (ChNPs) have been extensively examined for various biomedical applications due to their advantages include large surface area, biodegradability, and biocompatibility. The purpose of this research was to synthesize ChNPs using a simple ionic gelation technique by the interaction of low molecular weight chitosan (LMWC) and sodium tripolyphosphate (TPP) as a cross-linking agent. ChNPs, TPP, and LMWC were analysed by X-ray diffraction (XRD) and Fourier transforms infrared (FTIR) spectra that indicated the formation of ChNPs, attributing to the rearrangement of the nanoparticles after adding the TPP cross-linker into the LMWC solution. XRD analysis exhibited that ChNPs were amorphous, due to the effect of TPP cross-linker. Dynamic light scattering showed the nano-dimension of ChNPs with a hydrodynamic size of 68.50 nm. Thus, the obtained results indicated that the properties of chitosan were improved through converting it into nanoparticles using TPP initiated ionic gelation procedure.

Synthesis of Ag/ZnO Photocatalysts for the Photodegradation of Methyl Orange Dye

ZnO and a series of Ag/ZnO photocatalysts were prepared by a precipitation- irradiation method and their photocatalytic performance in photodegradation of methyl orange dye was evaluated. The physicochemical properties of the catalysts were characterized by various characterization techniques. The photocatalysts have a hexagonal phase and were highly agglomerated. TEM images showed a change in morphology of ZnO from rod to nearly spherical with the addition of Ag. Ag/ZnO catalysts exhibited better photocatalytic activity in the degradation of methyl orange compared to pure ZnO. Ag/ZnO contains 2% silver shows the best performance as photocatalyst.

Green synthesis of Sodium alginate mediated Fluorapatite Nanoparticle via Sol-Gel method

Fluorapatite (FA) can be used as a bioactive substance in the body, especially the teeth implants. The FA nanoparticle was synthesized by adding the fluorine to the structure of HA using sol–gel method and the heat treatment of 700 °C. Being low costs, eco-friendly and safer features are obvious advantages of the green synthesis of FA nanoparticles by using bio stabilizer of sodium alginate. Calcium nitrate tetrahydrate, diammonium phosphate, ammonium fluoride were used as precursors of Ca, P and F respectively with the ratio of 1:67 Ca/P. The presence of crystal structure of HA and FA investigated by the results of XRD which confirmed the substitution of hydroxyl groups with the fluorine in the crystal structure of apatite. FTIR obtained that fluorine was substituted by hydroxyl groups in the structure of fluoridated hydroxyapatite by disappearing the hydroxyl groups at 3600 cm-1 in the FA. TGA investigated the thermal stability of the nanoparticles that showed the discrepancy of weight loss for HA and FA between 600?C to 800?C. By using TEM, average sizes of 35 and 49 nm were determined for HA and FA respectively. FESEM results confirmed the shapes and distribution of particles of HA and FA in that, round like for the former and rode like for the later. The overall performance of utilizing sodium alginate (SA) as a bio-stabilizer is to obtain better precipitate which leads to having better crystallinity and smaller particle size and thermal stability remarkably improved.