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Polysaccharide nanocrystals have great potential to be used as improved drug carriers due to their low cost, high biodegradability, and biocompatibility. This study reports the synthesis of cellulose nanocrystals (CNC) loaded with 5-fluorouracil (CNC/5FU) to evaluate their anticancer activity against colorectal cancer cells. X-ray and Fourier-transform infrared spectroscopy demonstrated that acid hydrolysis successfully degraded the amorphous cellulose to liberate the crystal regions. From transmission electron microscopy, CNC/5FU appeared as rod-like nanocrystals with an average length and width of 69.53 ± 1.14 nm and 8.13 ± 0.72 nm, respectively. The anticancer drug 5FU showed improved thermal stability after being loading onto CNC. From UV-vis spectroscopy data, the drug encapsulation efficiency in CNC/5FU was estimated to be 83.50 ± 1.52%. The drug release of CNC/5FU was higher at pH 7.4 compared to those at pH 4.2 and 1.2. From the cytotoxicity assays, CNC did not affect the viability of CCD112 colon normal cells. On the other hand, CNC/5FU exhibited anticancer effects against HCT116 and HT-29 colorectal cancer cells. The anticancer actions of CNC/5FU against HCT116 cells were then confirmed using an in vitro tumor-on-chip model and clonogenic assay. Mechanistic studies demonstrated that CNC/5FU killed the cancer cells by mainly inducing cell apoptosis and mitochondrial membrane damage. Overall, this study indicated that CNC/5FU could be a potential nanoformulation for improved drug delivery and colorectal cancer treatment., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Core-shell Fe 3 O 4 /Au nanostructures were constructed using an advanced method of two-step synthesis from Juglans regia (walnut) green husk extract. Several complementary methods were applied to investigate structural and magnetic properties of the samples. X-ray diffraction (XRD), high-resolution transmission electron microscopy (HR-TEM), electron diffraction, optical, thermogravimetric analysis (TGA), and vibrating sample magnetometer (VSM) were used for nanoparticle characterizations. As shown by HR-TEM, the mean diameter of core-shell Fe 3 O 4 /Au nanoparticles synthesized using co-precipitation method was 6.08 ± 1.06 nm. This study shows that the physical and structural properties of core-shell Fe 3 O 4 /Au nanoparticles possess intrinsic properties of gold and magnetite. VSM revealed that the core-shell Fe 3 O 4 /Au have high saturation magnetization and low coercivity due to the magnetic properties. The core-shell nanoparticles show the inhibitory concentration (IC) 50 of 235 μg/ml against a colorectal cancer cell line, HT-29. When tested against non-cancer cells, IC 50 was not achieved even up to 500 μg/ml. This study highlights the magnetic properties and anticancer action of core-shell Fe 3 O 4 /Au nanoparticles. This compound can be ideal candidate for cancer treatment and other biomedical applications., (Copyright © 2018 Elsevier B.V. All rights reserved.)

DNA formulations provide the basis for safe and cost effective vaccine. Low efficiency is often observed in the delivery of DNA vaccines. In order to assess a new strategy for oral DNA vaccine formulation and delivery, plasmid encoding hemagglutinin (HA) gene of avian influenza virus, A/Ck/Malaysia/5858/04 (H5N1) (pcDNA3.1/H5) was formulated using green synthesis of sliver nanoparticles (AgNP) with polyethylene glycol (PEG). AgNP were successfully synthesized uniformly dispersed with size in the range of 4 to 18 nm with an average size of 11 nm. Cytotoxicity of the prepared AgNP was investigated in vitro and in vivo using MCF-7 cells and cytokine expression, respectively. At the concentration of -5 log₁₀AgNP, no cytotoxic effects were detected in MCF-7 cells with 9.5% cell death compared to the control. One-day-old specific pathogen-free (SPF) chicks immunized once by oral gavage with 10 μl of pcDNA3.1/H5 (200 ng/ml) nanoencapsulated with 40 μl AgNP (3.7×10⁻² μg of Ag) showed no clinical manifestations. PCR successfully detect the AgNP/H5 plasmid from the duodenum of the inoculated chicken as early as 1h post-immunization. Immunization of chickens with AgNP/H5 enhanced both pro inflammatory and Th1-like expressions, although no significant differences were recorded in the chickens inoculated with AgNP, AgNP/pcDNA3.1 and the control. In addition, serum samples collected from immunized chickens with AgNP/H5 showed rapidly increasing antibody against H5 on day 14 after immunization. The highest average antibody titres were detected on day 35 post-immunization at 51.2±7.5. AgNP/H5 also elicited both CD4+ and CD8+ T cells in the immunized chickens as early as day 14 after immunization, at 7.5±2.0 and 20±1.9 percentage, respectively. Hence, single oral administrations of AgNP/H5 led to induce both the antibody and cell-mediated immune responses as well as enhanced cytokine production., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Copper nanoparticles (Cu‐NPs) have garnered substantial interest in the field of nanotechnology due to their exceptional physical and chemical properties and cost‐effectiveness. However, challenges such as particle aggregation and rapid copper oxidation affect nanoscale production. This study systematically investigates the synthesis of colloidal Cu‐NPs using chitosan (Cts) as a stabilizer and reducing agent in the arc discharge system, comparing it to distilled water as a medium. Confirmation of the purity, size, and morphology of the Cu‐NPs is achieved through various physicochemical characterization methods. X‐ray diffraction patterns confirm the synthesis of highly pure face‐centered cubic (fcc) crystal Cu‐NPs. UV–vis analysis reveals absorption peaks at 572–585 nm, indicating pure copper. Fourier‐transform infrared spectroscopy shows peaks at 638 and 597 cm−1, corresponding to Cu─Cts bonds. Transmission electron microscopy images depict spherical nanoparticles ranging from 15 to 45 nm, with smaller sizes at higher Cts concentrations. The catalytic activity of Cu‐NPs in the degradation of 4‐nitrophenol to 4‐aminophenol is assessed, with Cu‐NPs synthesized in distilled water demonstrating superior catalytic properties compared to 0.10 wt.% Cts. This study highlights the efficacy of the arc discharge method in producing pure, uniformly sized Cu‐NPs with potential applications in catalysis. [ABSTRACT FROM AUTHOR]

This study presents a green synthesis approach for the fabrication of zinc oxide-silver nanoparticles (ZnO-Ag-NPs) using Punica granatum fruit peels extract as a natural reducing and stabilizing agent. This eco-friendly method offers a sustainable alternative to conventional methods that often employ toxic or hazardous chemicals. Antibacterial and anti-cancer activities of the green synthesized nanoparticles were then assessed in vitro. X-ray diffraction confirmed the production of ZnO-Ag-NPs with increasing crystallinity in higher pH values. The ZnO-Ag-NPs were found to be agglomerated with spherical AgNPs. Fourier Transform Infrared (FTIR) spectra revealed a broad band in ZnOAg-NPs ranging from 400-1 to 530 cm-1 with reduced intensity as compared to ZnO-NPs, indicating the formation of Ag-NPs on the surface of ZnO-NPs. The synthesized ZnO-Ag-NPs exhibited potent antibacterial activity against a broad spectrum of bacterial strains, particularly Gram-positive bacteria, with superior inhibition activity compared to ZnO-NPs. Moreover, ZnO-Ag-NPs showed a dosedependent anti-proliferative effect on colorectal-, lung-, and cervical cancer cells. ZnO-Ag-NPs showed significantly greater efficacy in inhibiting cancer cell growth at a lower concentration of 31.25 μg/mL, compared to ZnO-NPs which required over 500 μg/mL, possibly due to the presence of silver nanoparticles (Ag-NPs). The results obtained from this study demonstrate the potential of green synthesis approaches in the fabrication of therapeutic nanomaterials for cancer treatment, as well as other biomedical applications. [ABSTRACT FROM AUTHOR]

Mucosal surfaces are the first site of infection for most infectious diseases and oral vaccination can provide protection as the first line of defense. Unlike systemic administration, oral immunization can stimulate cellular and humoral immune responses at both systemic and mucosal levels to induce broad-spectrum and long-lasting immunity. Therefore, to design a successful vaccine, it is essential to stimulate the mucosal as well as systemic immune responses. Successful oral vaccines need to overcome the harsh gastrointestinal environment such as the extremely low pH, proteolytic enzymes, bile salts as well as low permeability and the low immunogenicity of vaccines. In recent years, several delivery systems and adjuvants have been developed for improving oral vaccine delivery and immunogenicity. Formulation of vaccines with nanoparticles and microparticles have been shown to improve antigen stability, availability and adjuvanticity as well as immunostimulatory capacity, target delivery and specific release. This review discusses how nanoparticles (NPs) and microparticles (MPs) as oral carriers with adjuvant characteristics can be beneficial in oral vaccine development. [ABSTRACT FROM AUTHOR]

Water is one of the humanity's major resources, but it is actually at risk due to growth and urbanization. Water reclamation and reuse was introduced as one of the solutions. However, the presence of organic pollutants, such as dyes, in the reclaim water can cause adverse effect to human. The dyes can be removed through photocatalysis process where semiconductor materials such as zinc oxide (ZnO) is used as the catalyst. In this research, several zinc oxide nanoparticles (ZnO NPs) were developed with pullulan as the capping agent through green synthesis. The impact of calcination conditions on the properties of synthesized ZnO NPs was explored. All the synthesized samples were subjected to photocatalytic degradation of two dyes, methyl orange (MO) and rhodamine B (RhB). The results indicated that with the increment of calcination temperature, the average particles size increased from 28.86 to 127.69 nm and the surface area reduced from 30.7996 to 12.3757 m2 g−1. As the calcination time changed, substantial impact was observed where, as calcination time increased to 2 h, the average particles size and the surface area significantly increased and reduced, respectively. The best photocatalytic degradation of MO and RhB was observed using ZnO NPs produced at 400 °C and 1 h calcination conditions. Overall, ZnO NPs have a good prospect to be applied for removal of dyes in wastewater. [ABSTRACT FROM AUTHOR]

A facile, environmental friendly green approach was introduced in this study, which superparamagnetic magnetite nanoparticles (Fe3O4-NPs) have been satisfactorily synthesized. Seaweed Kappaphycus alvarezii (K. alvarezii) extract was employed in this synthesis process, which played a role as bio-stabilizer. The structure and morphology of the synthesized K. alvarezii/Fe3O 4-NPs were analyzed by X-ray diffraction (XRD) and transmission electron microscope. The spherical shape of K. alvarezii/Fe3O4-NPs with an average size of 19.4 nm showed high crystallinity and purity based on the characteristic XRD planes at (220), (311), (400), (422), (511), (440), and (533). The presence of Fe3O4-NPs was identified by Fourier transform infrared, Raman spectroscopy, and energy-dispersive X-ray spectroscopy. The magnetic properties of K. alvarezii /Fe3O4-NPs were studied using vibrating sample magnetometer, which gave a result of 24.85 emu/g. The K. alvarezii/Fe3O4-NPs were very stable, where zeta potential value showed −53.57 mV. [ABSTRACT FROM PUBLISHER]

The production of gold nanoparticles using the aqueous peel extract of Garcinia mangostana plant is presented in this paper. The amount of peels powder and concentration of tetrachloroaurate salt were altered to determine the effect toward the nanoparticles. When the concentration of the starting materials increased, sharper peaks were observed in UV-vis spectroscopy at the region of 530 nm. The nanoparticles produced were spherical in shape with peel extract matrix surrounding them to prevent aggregation. The average size of the nanoparticles was 47.92±4.92 nm. The presence of gold nanoparticles with face centered cubic structure was confirmed by using XRD. The nanoparticles produced were relatively stable with a stability of –18.45 mV. This paper presents a facile and simple way to produce nontoxic nanoparticles that are environmental friendly and cost effective. [ABSTRACT FROM PUBLISHER]

An eco-friendly photochemical method for preparing silver nanoparticles (Ag-NPs) in a natural polymer (κ-carrageenan) was successfully developed and is reported in this study. The Ag-NPs have been synthesized via a photochemical method by using UV-irradiation, silver nitrate and κ-carrageenan as a reducing agent, a silver precursor and a stabilizer at room temperature, at different irradiation time. The formation of Ag-NPs was improved by UV–vis spectroscopy where surface plasmon absorption maxima was observed at 420–430 nm. Transmission electron microscopy (TEM) data and the size distribution were in an agreement with the finding from the UV–vis spectra. Scanning electron microscope data illuminated the changes in the surface of κ-carrageenan. Fourier transform infrared spectra indicated the interactions between Ag-NPs and κ-carrageenan. In addition, the Ag-NPs were characterized by X-ray diffraction (XRD). The peaks in the XRD pattern showed that the Ag-NPs possessed an FCC structure. The green methods by using an eco-friendly stabilizer and reducing agent provide green and economic attributes to this paper. These results demonstrate the successful synthesis of Ag-NPs in κ-carrageenan by using UV-irradiation as a green and a photochemical reducing method. Ag-NPs were obtained by using UV-irradiation at different times at room temperature, where increasing irradiation time corresponded to the formation of smaller more spherical Ag-NPs. The synthesized Ag-NPs find applications as bacteria inhibitors and can be applied in the medical field. [ABSTRACT FROM PUBLISHER]

A green sonochemical method was developed for preparing silver nanoparticles (Ag-NPs) in κ-carrageenan in different concentrations of AgNO. The κ-carrageenan was used as an eco-friendly stabilizer and ultrasonic irradiation as a green reducing agent. The number of Ag-NPs increased with increasing concentrations of AgNO. Formation of Ag/κ-carrageenan was determined by UV-visible spectroscopy where the surface plasmon absorption maximum was observed at 410-416 nm. XRD analysis showed the Ag-NPs are of a face-centered cubic structure. TEM images showed the well-dispersed Ag-NPs with an average particle size <5 nm. SEM images showed the spherical shape of the Ag-NPs. The FT-IR spectrum indicated the presence of κ-carrageenan in capping the Ag-NPs. The use of photo irradiation provides a green and economic method features to the synthesis reported in this study. [ABSTRACT FROM AUTHOR]

The sonochemical method as a green method for the preparation and size control of silver nanoparticles (Ag-NPs) formed in κ-carrageenan has been developed. κ-carrageenan was chosen because it is an eco-friendly stabilizer and ultrasonic irradiation reducing agent. Formations of Ag/κ-carrageenan were determined by electronic spectroscopy where the surface plasmon absorption maxima were observed at 437-412 nm. The FT-IR spectrum indicated the presence of κ-carrageenan in capping with Ag-NPs. The XRD analysis proved that the Ag-NPs were of a face-centered cubic structure. TEM images displayed well-dispersed Ag-NPs with an average particle size of less than 10 nm. SEM images indicated the spherical shape of the Ag-NPs. [ABSTRACT FROM AUTHOR]

The goal of this study was to prepare nanocomposites of rice straw coated with different percentages of Fe3O4 nanoparticles (Fe3O4-NPs) [1.0, 5.0, 10.0, and 20.0 wt. %]. In this process, the size of Fe3O4-NPs changed with varying volumes of NaOH (2M). The Fe3O4-NPs were precipitated with sodium hydroxide from a solution of Fe(II) and (III) chloride in water under ambient conditions and N2 gas by the quick precipitation method using urea as a stabilizer. The rice straw/Fe3O4 nanocomposites (NCs) prepared by this method had magnetic properties in percentages higher than ten (10 wt. %). When the volume of NaOH increased, Fe3O4-NPs with uniform size and better distribution could be prepared, which means that the size of the NPs decreased as the reducing agent was increased. Transmission electron microscopy (TEM) showed that Fe3O4-NPs in rice straw were spherical with diameters from 18.47 to 9.93 nm. The SEM results show that the structure of rice straw underwent no particular change. EDX indicated the presence of Fe3O4- NPs on the surface of rice straw. X-ray powder diffraction (PXRD) indicated that the magnetic Fe3O4-NPs were pure and that the particles were small. The FT-IR results showed that the Fe3O4-NPs were successfully coated on the surface of rice straw. [ABSTRACT FROM AUTHOR]

Copper nanoparticles (Cu-NPs) were prepared in virgin coconut oil (VCO) using a laser ablation technique. A copper plate immersed in VCO was irradiated by an Nd:YAG laser at wave lengths of 532 nm for 5, 10, 20, and 30 min. By increasing the ablation time from 5 to 30 min, the particle size inside the nanofluid decreased from 11 to 4 nm and the concentration, refractive index, and the volume fraction of copper nanofluid increased. The Cu-NPs were capped with oxygen from hydroxyl groups of the VCO, as verified by Fourier transform infrared spectroscopy. The refractive indices, obtained by analysis of the surface plasmon resonance signals increased from 1.44371 + 0.0034i to 1.44387 + 0.0142i, and special self-phase modulation due to nonlinearity effect was investigated. [ABSTRACT FROM AUTHOR]

A novel nano-adsorbent SiO/(3-aminopropyl)triethoxysilane-coated magnetite nanoparticles was synthesized for the adsorption of lead ions from water samples. Its structure and magnetic characteristics were characterized, by FTIR, powder X-ray diffraction, scanning electron microscope (SEM), transmission electron microscope (TEM) and vibrating sample magnetometry (VSM). Amino-functionalized SiO coated FeO magnetite nano-adsorbent exhibited superparamagnetic behavior and strong magnetization at room temperature. The efficiency of the nano-adsorbent in separation of the metals was evaluated by adsorption technique. Kinetic data were analyzed using the pseudo-first-order and pseudo-second-order equations. The data fitted very well to the pseudo-second-order kinetic model.The linear Langmuir and Freundlich models were applied to describe equilibrium isotherms and Langmuir model fitted well. The monolayer adsorption capacity was found as 17.65 mg/g at pH 4.0. Thermodynamic parameters such as free energy change (ΔG°), enthalpy change (ΔH°) and entropy change (ΔS°) were also calculated. These parameters showed that the adsorption of Pb(II) onto nano-adsorbent was feasible, spontaneous and endothermic. The amino-functionalized SiO coated FeO magnetic nano-adsorbent shows high adsorption capability for metal ions from aqueous solutions via the chelation mechanisms. The Pb(II) loaded nano-adsorbent can be easily recovered from aqueous solution with magnetic separation and regenerated readily by acid treatment. The product of this work can be used as an effective and recyclable nano-adsorbent for the removal of metal ions in wastewater treatment. [ABSTRACT FROM AUTHOR]

Nickel nanoparticles were dispersed uniformly in a graphene oxide solution, using a laser ablation technique with different ablation times that ranged from 5 to 20 minutes. The results indicate that the nickel nanoparticle sizes inside the graphene oxide decreased, and the volume fraction for the nickel nanoparticles in the graphene oxide increasedwith an increasing ablation time. Further, using Fourier Transform Infrared Spectroscopy, the nickel nanoparticles in the graphene oxide demonstrate greater stability from possible Agglomeration when the nanoparticle was capped with oxygen from the carboxyl group of the graphene oxide. The thermal effusivity of the graphene oxide and nickel nanoparticle graphene oxide composite was measured using a photoacoustic technique. The concentration of graphene oxide shifted from0.05mg/L to 2mg/L, and the thermal effusivity increased from0.153W·s1/2 ·cm-2 ·K-1 to 0.326W·s1/2 ·cm-2 ·K-1. In addition, the thermal effusivity of the nickel nanoparticles graphene oxide composite increased with an increase in the volume fraction of nickel nanoparticles from 0.1612W·s1/2 ·cm-2 ·K-1 to 0.228WW·s1/2 ·cm-2 ·K-1. [ABSTRACT FROM AUTHOR]

Background: This study aims to investigate the influence of different stirring times on antibacterial activity of silver nanoparticles in polyethylene glycol (PEG) suspension. The silver nanoparticles (Ag-NPs) were prepared by green synthesis method using green agents, polyethylene glycol (PEG) under moderate temperature at different stirring times. Silver nitrate (AgNO3) was taken as the metal precursor while PEG was used as the solid support and polymeric stabilizer. The antibacterial activity of different sizes of nanosilver was investigated against Gram-positive [Staphylococcus aureus] and Gram-negative bacteria [Salmonella typhimurium SL1344] by the disk diffusion method using Müeller-Hinton Agar. Results: Formation of Ag-NPs was determined by UV-vis spectroscopy where surface plasmon absorption maxima can be observed at 412-437 nm from the UV-vis spectrum. The synthesized nanoparticles were also characterized by X-ray diffraction (XRD). The peaks in the XRD pattern confirmed that the Ag-NPs possessed a face-centered cubic and peaks of contaminated crystalline phases were unable to be located. Transmission electron microscopy (TEM) revealed that Ag-NPs synthesized were in spherical shape. The optimum stirring time to synthesize smallest particle size was 6 hours with mean diameter of 11.23 nm. Zeta potential results indicate that the stability of the Ag-NPs is increases at the 6 h stirring time of reaction. The Fourier transform infrared (FT-IR) spectrum suggested the complexation present between PEG and Ag-NPs. The Ag-NPs in PEG were effective against all bacteria tested. Higher antibacterial activity was observed for Ag-NPs with smaller size. These suggest that Ag-NPs can be employed as an effective bacteria inhibitor and can be applied in medical field. Conclusions: Ag-NPs were successfully synthesized in PEG suspension under moderate temperature at different stirring times. The study clearly showed that the Ag-NPs with different stirring times exhibit inhibition towards the tested gram-positive and gram-negative bacteria. [ABSTRACT FROM AUTHOR]

Abstract: The optimization processes of photo degradation are complicated and expensive when it is performed with traditional methods such as one variable at a time. In this research, the condition of ortho-cresol (o-cresol) photo degradation was optimized by using a semi empirical method. First of all, the experiments were designed with four effective factors including irradiation time, pH, photo catalyst's amount, o-cresol concentration and photo degradation % as response by response surface methodology (RSM). The RSM used central composite design (CCD) method consists of 30 runs to obtain the actual responses. The actual responses were fitted with the second order algebraic polynomial equation to select a model (suggested model). The suggested model was validated by a few numbers of excellent statistical evidences in analysis of variance (ANOVA). The used evidences include high F-value (143.12), very low P-value (<0.0001), non-significant lack of fit, the determination coefficient (R2 = 0.99) and the adequate precision (47.067). To visualize the optimum, the validated model simulated the condition of response (photo degradation %) be using a few number of three dimensional plots (3D). To confirm the model, the optimums were performed in laboratory. The results of performed experiments were quite close to the predicted values. In conclusion, the study indicated that the model is successful to simulate the optimum condition of o-cresol photo degradation under visible-light irradiation by manganese doped ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

In this research, silver nanoparticles (AgNPs) were synthesized in chitosan (Cts), Cts/gelatin and gelatin suspensions using a chemical reducing agent. Cts and gelatin were used as natural stabilizers and solid support, whereas AgNO3 was used as the silver precursor. Sodium borohydride (NaBH4) was used as the reducing agent. The properties of AgNPs in Cts, Cts/gelatin and gelatin bionanocomposites (BNCs) were studied in terms of their surface plasmon resonance, crystalline structure, average diameter size, particle distributions, surface topography and functional groups. All the samples were characterized by UV-visible spectroscopy, powder X-ray diffraction, transmission electron microscopy, atomic force microscopy and Fourier transform infrared spectroscopy. [ABSTRACT FROM AUTHOR]

This paper presents the green synthesis of silver nanoparticles (Ag NPs) in aqueous medium. This method was performed by reducing AgNO3 in different stirring times of reaction at a moderate temperature using green agents, chitosan (Cts) and polyethylene glycol (PEG). In this work, silver nitrate (AgNO3) was used as the silver precursor while Cts and PEG were used as the solid support and polymeric stabilizer. The properties of Ag/Cts/PEG nanocomposites (NCs) were studied under different stirring times of reaction. The developed Ag/Cts/PEG NCs were then characterized by the ultraviolet-visible (UV-Vis) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectroscopy. [ABSTRACT FROM AUTHOR]

Different biological methods are gaining recognition for the production of silver nanoparticles (Ag-NPs) due to their multiple applications. One of the most important applications of Ag-NPs is their use as an anti-bacterial agent. The use of plants in the synthesis of nanoparticles emerges as a cost effective and eco-friendly approach. In this study the biosynthesis of silver nanoparticles using Vitex negundo L. extract and its antimicrobial properties has been reported. The resulting silver particles are characterized using transmission electron microscopy (TEM), X-ray diffraction (XRD) and UV-Visible (UV-Vis) spectroscopic techniques. The TEM study showed the formation of silver nanoparticles in the 10-30 nm range and average 18.2 nm in size. The XRD study showed that the particles are crystalline in nature, with a face centered cubic (fcc) structure. The silver nanoparticles showed the antimicrobial activity against Gram positive and Gram negative bacteria. Vitex negundo L. was found to display strong potential for the synthesis of silver nanoparticles as antimicrobial agents by rapid reduction of silver ions (Ag+ to Ag0). [ABSTRACT FROM AUTHOR]

Silver nanoparticles (Ag-NPs) were successfully synthesized in the natural polymeric matrix. Silver nitrate, gelatin, glucose, and sodium hydroxide have been used as silver precursor, stabilizer, reducing agent, and accelerator reagent, respectively. This study investigated the role of NaOH as the accelerator. The resultant products have been confirmed to be Ag-NPs using powder X-ray diffraction (PXRD), UV-vis spectroscopy, and transmission electron microscopy (TEM). The colloidal sols of Ag-NPs obtained at different volumes of NaOH show strong and different surface plasmon resonance (SPR) peaks, which can be explained from the TEM images of Ag-NPs and their particle size distribution. Compared with other synthetic methods, this work is green, rapid, and simple to use. The newly prepared Ag-NPs may have many potential applications in chemical and biological industries. [ABSTRACT FROM AUTHOR]

Discovery of a novel anticancer drug delivery agent is important to replace conventional cancer therapies which are often accompanied by undesired side effects. This study demonstrated the synthesis of superparamagnetic magnetite nanocomposites (Fe3O4-NCs) using a green method. Montmorillonite (MMT) was used as matrix support, while Fe3O4 nanoparticles (NPs) and carrageenan (CR) were used as filler and stabilizer, respectively. The combination of these materials resulted in a novel nanocomposite (MMT/CR/Fe3O4-NCs). A series of characterization experiments was conducted. The purity of MMT/CR/Fe3O4-NCs was confirmed by X-ray diffraction (XRD) analysis. High resolution transmission electron microscopy (HRTEM) analysis revealed the uniform and spherical shape of Fe3O4 NPs with an average particle size of 9.3 ± 1.2 nm. Vibrating sample magnetometer (VSM) analysis showed an Ms value of 2.16 emu/g with negligible coercivity which confirmed the superparamagnetic properties. Protocatechuic acid (PCA) was loaded onto the MMT/CR/Fe3O4-NCs and a drug release study showed that 15% and 92% of PCA was released at pH 7.4 and 4.8, respectively. Cytotoxicity assays showed that both MMT/CR/Fe3O4-NCs and MMT/CR/Fe3O4-PCA effectively killed HCT116 which is a colorectal cancer cell line. Dose-dependent inhibition was seen and the killing was enhanced two-fold by the PCA-loaded NCs (IC50–0.734 mg/mL) compared to the unloaded NCs (IC50–1.5 mg/mL). This study highlights the potential use of MMT/CR/Fe3O4-NCs as a biologically active pH-responsive drug delivery agent. Further investigations are warranted to delineate the mechanism of cell entry and cancer cell killing as well as to improve the therapeutic potential of MMT/CR/Fe3O4-NCs. [ABSTRACT FROM AUTHOR]

Nanoparticles (NPs) are nano-sized particles (generally 1–100 nm) that can be synthesized through various methods. The wide range of physicochemical characteristics of NPs permit them to have diverse biological functions. These particles are versatile and can be adopted into various applications, particularly in biomedical field. In the past five years, NPs’ roles in biomedical applications have drawn considerable attentions, and novel NPs with improved functions and reduced toxicity are continuously increasing. Extensive studies have been carried out in evaluating antibacterial potentials of NPs. The promising antibacterial effects exhibited by NPs highlight the potential of developing them into future generation of antimicrobial agents. There are various methods to synthesize NPs, and each of the method has significant implication on the biological action of NPs. Among all synthetic methods, green technology is the least toxic biological route, which is particularly suitable for biomedical applications. This mini-review provides current update on the antibacterial effects of NPs synthesized by green technology using plants. Underlying challenges in developing NPs into future antibacterials in clinics are also discussed at the present review. [ABSTRACT FROM AUTHOR]

The artificial neural network (ANN) models have the capacity to eliminate the need for expensive experimental investigation in various areas of manufacturing processes, including the casting methods. Determination of particle size is one of the critical parameters in nanotechnology.TheAg-NPs have attracted significant attention for chemical, physical and clinical applications due to their exceptional properties.The nanosilver crystals were prepared in the biopolymer mediated without any aggregation by using green chemical reduction method. The method has an advantage of size control which is essential in nano-metal synthesis. The resulting of silver nanoparticles (Ag-NPs) characterized by using of X-ray diffraction (XRD) and transmission electron microscopy (TEM) technique.XRD patterns confirmed that Ag-NPs crystallographic planes were face centered cubic (fcc) type. TEM results showed that mean diameters of Ag-NPs for four different amounts of variables were less than 40 nm. This method with comparison to other methods is green, high yield, speedy and easy to use.This paper presents an ANN model for the predictionsize of Ag-NPs by green method. Themodel accounts for the effect of NaOH volumes, temperature, stabilizer, and AgNO3 concentration on the size of nanoparticle.The best model presented a trustworthy agreement in predicting experimental data. The characteristic parameters of the presented ANN models are fully reported in the paper. [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]