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The aim of this study was to investigate the physicochemical characteristics of nanoparticles formed by the ionic gelation method between chitosan and water-soluble fraction of Persian gum (WPG) for encapsulation of Nigella sativa extract (NSE) as an antiviral agent. Our findings revealed that the particle size, polydispersity index (PDI), and zeta potential of the particles were in the range of 316.7-476.6 nm, 0.259-0.466, and 37.0-58.1 mV, respectively. The amounts of chitosan and WPG as the wall material and the NSE as the core had a considerable impact on the nanoparticle properties. The proper samples were detected at 1:1 chitosan:WPG mixing ratio (MR) and NSE concentration of 6.25 mg/mL. Fourier-transformed infrared (FTIR) spectroscopy proved the interactions between the two biopolymers. The effect of NSE on infectious bronchitis virus (IBV) known as avian coronavirus, was performed by the in-ovo method determining remarkable antiviral activity of NSE (25 mg/mL) and its enhancement through encapsulation in the nanoparticles. These nanoparticles containing NSE could have a promising capability for application in both poultry industry and human medicine as an antiviral product., Competing Interests: Declaration of competing interest The authors declare that they have no competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Zinc oxide nanoparticles (ZnO NPs) are used in a range of applications, including food packaging, preservation, and storage. In the current investigation, extracellular green synthesis of ZnO NPs through an simple, eco-friendly, and rapid approach using a novel bacterial strain (Bacillus subtilis NH1-8) was studied. To assess the morphological, optical, and structural properties of ZnO NPs, transmission electron microscopy (TEM), energy-dispersive X-ray (EDX), scanning electron microscopy (SEM), fourier transform infrared (FTIR) spectroscopy, ultraviolet-visible (UV-vis) spectroscopy, and X-ray diffraction (XRD) techniques were carried out. In addition, disk diffusion, minimum bactericidal concentration (MBC), and minimum inhibitory concentration (MIC) methods were performed to determine the antibacterial activity of ZnO NPs. The average size of biosynthesized ZnO NPs was 39 nm, exhibiting semi-spherical, which was confirmed by TEM analyses. The UV-vis spectroscopy exhibited the absorption peak at 200-800nm. The ZnO NPs have shown effective antimicrobial and antibiofilm activities against S. typhimurium. Thus, biosynthesized ZnO NPs could be exploited as a breakthrough technology in the surface coating of food containers and cans to minimize contamination by S. typhimurium., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Background: Curcumin is a main bioactive constituent of turmeric (Curcuma longa L.) with pleiotropic health beneficial effects. However, poor bioavailability is the major barrier to the efficient pharmacological effects of curcumin in humans., Aims: The present study aimed to develop liposome formulations based on soybean phosphatidylcholine (SPC) and hydrogenated SPC (HSPC) to enhance the bioavailability of curcumin in bladder cancer cells., Methods: Curcumin was encapsulated in HSPC and SPC liposome nanoparticles using the solvent evaporation method. Physical properties, encapsulation efficiency (%), stability, and in vitro drug release of the prepared liposome formulations have been evaluated. The cellular uptake and cytotoxicity of curcumin-encapsulated nanoliposomes on bladder carcinoma HTB9 cell line and normal fibroblast L929 cell line were studied. DNA fragmentation, apoptosis, and genotoxicity assessments have been carried out to determine the molecular mechanisms underlying the cytotoxic effects of liposomal curcumin formulations on bladder cancer cells., Results: The results indicated that curcumin could be efficiently encapsulated in the HSPC and SPC liposome formulations. The liposomal curcumin formulations have shown shelf-life stability for 14 weeks at 4°C. The accelerated stability testing showed that curcumin encapsulated in nanoliposomes was significantly (p < 0.001) more stable than free curcumin at various pH degrees ranging from alkaline to acidic pH. The in vitro drug release study showed curcumin to be sustainably released from the liposome nanoparticles. Of note, SPC and HSPC nanoliposome formulations significantly increased the cellular uptake and cytotoxicity of curcumin on bladder cancer HTB9 cells. Mechanistically, liposomal curcumin was found to exert a selective inhibitory effect on the viability of cancer cells by inducing apoptosis and DNA damage., Conclusion: In conclusion, SPC and HSPC liposome nanoparticles can significantly increase the stability and bioavailability of curcumin, which are important for improving its pharmacological effect., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Multifunctional nanoplatforms based on novel bimetallic nanoparticles have emerged as effective radiosensitizers owing to their potential capability in cancer cells radiosensitization. Implementation of chemotherapy along with radiotherapy, known as synchronous chemoradiotherapy, can augment the treatment efficacy. Herein, a tumor targeted nanoradiosensitizer with synchronous chemoradiotion properties, termed as CuFe 2 O 4 @BSA-FA-CUR, loaded with curcumin (CUR) and modified by bovine serum albumin (BSA) and folic acid (FA) was developed to enhance tumor accumulation and promote the anti-cancer activity while attenuating adverse effects. Both copper (Cu) and iron (Fe) were utilized in the construction of these submicron scale entities, therefore strong radiosensitization effect is anticipated by implementation of these two metals. The structure-function relationships between constituents of nanomaterials and their function led to the development of nanoscale materials with great radiosensitizing capacity and biosafety. BSA was used to anchor Fe and Cu ions but also to improve colloidal stability, blood circulation time, biocompatibility, and further functionalization. Moreover, to specifically target tumor sites and enhance cellular uptake, FA was conjugated onto the surface of hybrid bimetallic nanoparticles. Finally, CUR as a natural chemotherapeutic agent was encapsulated into the developed bimetallic nanoparticles. With incorporation of all abovementioned stages into one multifunctional nanoplatform, CuFe 2 O 4 @BSA-FA-CUR is produced for synergistic chemoradiotherapy with positive outcomes. In vitro investigation revealed that these nanoplatforms bear excellent biosafety, great tumor cell killing ability and radiosensitizing capacity. In addition, high cancer-suppression efficiency was observed through in vivo studies. It is worth mentioning that co-use of CuFe 2 O 4 @BSA-FA-CUR nanoplatforms and X-ray radiation led to complete tumor ablation in almost all of the treated mice. No mortality or radiation-induced normal tissue toxicity were observed following administration of CuFe 2 O 4 @BSA-FA-CUR nanoparticles which highlights the biosafety of these submicron scale entities. These results offer powerful evidence for the potential capability of CuFe 2 O 4 @BSA-FA-CUR in radiosensitization of malignant tumors and opens up a new avenue of research in this area., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The multi-template molecularly imprinted polymers reinforced with hybrid oxide nanoparticles were developed for the selective separation and determination of the trace level of naproxen (NPX), methocarbamol (MTH), and omeprazole (OMZ) simultaneously from biological and pharmaceutical samples. The polymers were constructed by magnetic core@shell molecularly imprinted polymer nanocomposite (Fe 3 O 4 /ZnO/CuO/MWCNT@MIP). An electrochemical sensor has been fabricated for this purpose. Fe 3 O 4 /ZnO/CuO/MWCNT nanocomposite was introduced to improve the electron transport capability and increase the sensor surface area, as well as enhance the electronic conductivity. The triple-template MIP-coated layer provides simultaneous selective identification of three analytes by using [Fe (CN) 6 ] 3-/4- as the redox probe. Electrochemical behavior of MTH, NPX, and OMZ on the modified electrode (Fe 3 O 4 /ZnO/CuO/MWCNT@MIP) by various techniques such as cyclic voltammetry, differential pulse voltammetry, and chronoamperometry was examined. The morphology of the modified and unmodified carbon paste electrodes was performed by scanning electron microscopy (SEM) and X-ray diffraction analysis (XRD). The average crystal size for fabricated nanoparticles obtained by calculating the X-ray diffraction technique was 17 nm in the Scherer method. The particle size which was determined by SEM was 48 nm. Some electrochemical parameters such as the diffusion coefficient and electron transfer coefficient were determined. The effect of many variables such as the pH and scan rate was also investigated. Under optimal conditions, the sensor is designed in the linear range 5.0 nM-100 μM and 5.0 nM-100 μM and 1.0 nM-130 μM with a detection limit of 1.5 nM, 1.0 nM, and 0.7 nM for measurement OMZ, NPX, and MTH, respectively. The relative standard deviation (RSD) of the five measurements was 1.21%, 2.23%, and 2.56% for NPX, MTH, and OMZ. Finally, the designed sensor was successfully used for simultaneous detection of target analytes in the real samples; tablets, water samples, and biological samples., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

An optimal radiosensitizer with improved tumor retention has an important effect on tumor radiation therapy. Herein, gold nanoparticles (Au NPs) and drug-containing, mPEG-conjugated CUR (mPEG-CUR), self-assembled NPs (mPEG-CUR@Au) are developed and evaluated as a drug carrier and radiosensitizer in a breast cancer mice model. As a result, cancer therapy efficacy is improved significantly by applying all-in-one NPs to achieve synchronous chemoradiotherapy, as evidenced by studies evaluating cell viability, proliferation, and ROS production. In vivo anticancer experiments show that the mPEG-CUR@Au system improves the radiation sensitivity of 4T1 mammary carcinoma and completely abrogates breast cancer., (© 2021 Wiley-VCH GmbH.)

Lipid-based nanoparticles, as drug delivery carriers, are commonly used for the delivery of anti-cancer therapeutic agents. Due to their smaller particle size and similarity to cell membranes, Lipid-based nanoparticles are readily internalized into cancer cells. Cancer cells also overexpress receptors for specific ligands, including folic acid, hyaluronic acid, and transferrin, on their surface, thus, allowing the use of their ligands for surface modification of the lipid-based nanoparticles for their specific recognition by receptors on cancer cells. This would also allow the gradual intracellular accumulation of the targeted functionalized nanoplatforms. These ligand-receptor interactions eventually enhance the internalization of desired drugs by increasing the nanoplatforms cellular uptake. The cellular internalization of the nanoplatforms varies and depends on their physicochemical properties, including particle size, zeta potential, and shape. The cellular uptake is also influenced by the types of ligand internalization pathways utilized by cells, such as phagocytosis, macropinocytosis, and multiple endocytosis pathways. This review classifies and discusses lipidbased nanoparticles engineered to carry specific ligands, their recognition by receptors on cancer cells, and their cellular internalization pathways. Moreover, the intracellular fate of nanoparticles decorated with specific ligands and their best internalization pathway (caveolae-mediated endocytosis) for safe cargo delivery are also discussed., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

The use of liposomes as drug carriers improves the therapeutic efficacy of anticancer drugs, while at the same time reducing side effects. Hyaluronic acid (HA) is recognized by the CD44 receptor, which is overexpressed in many cancer cells. In this study, we developed HA-modified liposomes encapsulating 5-fluorouracil (5-FU) and tested them against a CD44 expressing colorectal cell line (HT29) and a non-CD44 expressing hepatoma cell line. The average size of 5-FU-lipo and 5-FU-lipo-HA nanoparticles were 112 ± 28 and 144 ± 77 nm, respectively. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium (MTT) assay showed selective cancer cell death depending on the CD44 expression in a time-dependent manner. Apoptosis assays and cell-cycle analysis indicated that G0/G1 arrest occurred. The colony formation study revealed that cells treated with 5-FU-lipo and 5-FU-lipo-HA had reduced colony formation. Quantitative reverse-transcription polymerase chain reaction study showed that the oncogenic messenger RNA and microRNA levels were significantly reduced in the 5-FU-lipo-HA-treated group, while tumor suppressors were increased in that group. We suggest that optimal targeted delivery and release of 5-FU into colorectal cancer cells, renders them susceptible to apoptosis, cell-cycle arrest, and decreased colony formation., (© 2020 Wiley Periodicals, Inc.)

Background: Despite therapeutics based on siRNA have an immense potential for the treatment of incurable diseases such as cancers. However, the in vivo utilization of siRNA and also the delivery of this agent to the target site is one of the most controversial challenges. The helpful assistance by nanoparticles can improve stable delivery and also enhance efficacy. More nanoparticle-based siRNA therapeutics is expected to become available in the near future., Methods: The search strategy followed the guidelines of the Centre of Reviews and Dissemination. The studies were identified from seven databases (Scopus, Web of Science, Academic Search Premiere, CINAHL, Medline Ovid, Eric and Cochrane Library). Studies was selected based on titles, abstracts and full texts., Results: One hundred twenty nine papers were included in the review. These papers defined hurdles in RNAi delivery and also strategies to overcome these hurdles. This review discussed the existing hurdles for systemic administration of siRNA as therapeutic agents and highlights the various strategies to overcome these hurdles, including lipid-based nanoparticles and polymeric nanoparticles, and we also briefly reviewed chemical modification., Conclusion: Delivery of siRNA to the target site is the biggest challenge for its application in the clinic. The findings of this review confirmed by encapsulation siRNA in the nanoparticles can overcome these challenges. The rapid progress in nanotechnology has enabled the development of effective nanoparticles as the carrier for siRNA delivery. However, our data about siRNA-based therapeutics and also nanomedicine are still limited. More clinical data needs to be completely understood in the benefits and drawbacks of siRNA-based therapeutics. Prospective studies must pay attention to the in vivo safety profiles of the different delivery systems, including uninvited immune system stimulation and cytotoxicity. In essence, the development of nontoxic, biocompatible, and biodegradable delivery systems for medical application of RNAi-based therapeutics is needed., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Chitosan-coated human serum albumin nanoparticles were functionalized by MUC1 aptamer to obtain a selective drug carrier toward cancers overexpressing MUC1. The negative charges of albumin nanoparticles were shifted to positive charges by surface modification with chitosan, and MUC1 was conjugated through an acrylate spacer. The cytotoxicity of targeted nanoparticles was significantly more than non-aptamer nanoparticles, and also the chitosan-coated nanoparticles had more cytotoxic effects than the negatively charged albumin nanoparticles. The IC 50 of targeted nanoparticles was 28 and 26% of free paclitaxel in MCF7 and T47D cells at 48h, respectively. Confocal laser scanning electron microscopy showed that aptamer conjugation and positive charge increase the cellular uptake. 66% of paclitaxel was released within 32h, but 100% of drug was released at pH=5.5 (similar cancer cells). The paclitaxel plasma amount was at a good level of 17.6% at 2h for increasing the chance of cellular uptake., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Water dispersible, highly efficient nickel doped CdS nanoparticles anchored on graphene nanosheets as a photocatalyst for cephalexin and sulfamethoxazole photodegradation have been prepared in a facile microwave-furnace assisted method. Each one of the two modifications has played a critical role in nanocomposite functioning. Defects originated by dopant boosted the lifetime of carriers and thereupon graphene matrix transferred them to contribute effectively the photocatalytic process. Characterization results revealed the formation of monocrystalline hexagonal phase of all products and that both doping and loading on graphene have red-shifted the absorption edge of CdS towards the visible light region. Furthermore, FTIR confirmed the successful reduction of graphene oxide by the subsequent preparation steps. Adsorption isotherms revealed the role of graphene in enhancing substrate adsorption. Nevertheless, dissimilar pathways of catalytic degradation were observed on the doped composite as cephalexin oxidation was principally mediated by the hole-hydroxyl radical mechanism, sulfamethoxazole oxidation favored the superoxide radical mechanism. This composite has shown, however, a high photostability and minimized ions release of the composite., (Copyright © 2016 Elsevier B.V. All rights reserved.)

The aim of this work was to synthesize molecularly imprinted polymer-poly ethylene glycol-folic acid (MIP-PEG-FA) nanoparticles for use as a controlled release carrier for targeting delivery of paclitaxel (PTX) to cancer cells. MIP nanoparticles were synthesized by a mini-emulsion polymerization technique and then PEG-FA was conjugated to the surface of nanoparticles. Nanoparticles showed high drug loading and encapsulation efficiency, 15.6 ± 0.8 and 100%, respectively. The imprinting efficiency of MIPs was evaluated by binding experiments in human serum. Good selective binding and recognition were found in MIP nanoparticles. In vitro drug release studies showed that MIP-PEG-FA have a controlled release of PTX, because of the presence of imprinted sites in the polymeric structure, which makes it is suitable for sustained drug delivery. The drug release from polymeric nanoparticles was indeed higher at acidic pH. The molecular structure of MIP-PEG-FA was confirmed by Hydrogen-Nuclear Magnetic Resonance (H NMR), Fourier Transform InfraRed (FT-IR), and Attenuated Total Reflection (ATR) spectroscopy, and their thermal behaviors by Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Scanning Electron Microscopy (SEM) and Photon Correlation Spectroscopy (PCS) results showed that nanoparticles have a smooth surface and spherical shape with an average size of 181 nm. MIP-PEG-FA nanoparticles showed a greater amount of intracellular uptake in folate receptor-positive cancer cells (MDA-MB-231 cells) in comparison with the non-folate nanoparticles and free PTX, with half maximal inhibitory concentrations (IC50) of 4.9 ± 0.9, 7.4 ± 0.5 and 32.8 ± 3.8 nM, respectively. These results suggest that MIP-PEG-FA nanoparticles could be a potentially useful drug carrier for targeting drug delivery to cancer cells., (Copyright © 2016. Published by Elsevier B.V.)

Nanoparticles have been considered in many fields such as medicine and industry due to their very small size and their special physicochemical properties. Biosynthesis of nanoparticles has advantages over other methods. This paper examines the bibliography of the relationship between nanotechnology and fungi from 1985 to 2021. Data were collected from three databases consisting of Web of Science, Scopus, and Dimensions. The number and type of documents were examined and then the analysis was continued using VOSviewer and Bibliometrix-package on the documents of the Scopus database. Analysis of 1203 documents from this database showed an upward trend in the publication in recent years. The term "Fungi" was also identified as the keyword index and India as the country with the most published documents. Future research is likely to be on using modern techniques in the study of nanoparticles as well as focusing on other genera of fungi. This paper explores the relationship between nanotechnology and fungi from 1985 to 2021. Biosynthesis offers advantages in creating nanoparticles, which are tiny particles with unique properties used in many fields. Data from three databases were analysed, indicating an increasing trend in publications in recent years. Future research is likely to focus on modern techniques to study nanoparticles and other types of fungi. [ABSTRACT FROM AUTHOR]

The growth trend of publications in the field of nanoparticles biosynthesis by bacteria was analyzed using bibliometric techniques to the identification of the areas with significant development and the orientations that have guided the research on bacteria. This study extracted data from the Clarivate Analytics Web of Science (WoS) and Scopus between 2000 and 2020 to compare results. The number of articles published annually, participating countries, resource growth rate, most used keywords and research collaborations were obtained from bibliometric analysis. The results showed that nanoparticle documents in materials science, biochemistry, genetics and molecular biology have improved citation rates as the authors researched in multidisciplinary areas. Although these keywords have the most sites, they are not emerging keywords, and their most common use was in the years 2014–2018. The results showed the upward trend of articles published from 2000 to 2020, most of which were related to the last 10 years. The 5 countries that had the most articles published in this field were China, USA, India, Germany and Iran. The top sources that had the most published documents in this field had a similar scope to our research. The results of each section had a significant relationship with other sections of this study. VOS viewer program was used for quantitative analysis. It seems that bibliometric methods will complement meta-analysis and qualitative structured literature reviews as a method for reviewing and evaluating scientific literature. The advantage of the bibliographic analysis was the awareness of trends in a study area. Documents by subject area of Nanoparticle Biosynthesis by Bacteria that related to material science. [ABSTRACT FROM AUTHOR]

Purpose: This study was aimed to evaluate the site-specific drug delivery of 5-FU with chitosan (CS) as a carrier and quercetin (Qu) against induced colon cancer in Wistar rats. Methods: Cross-linked CS-Qu nanoparticles (NPs) were prepared by ionotropic gelation method. Physicochemical characterization of NPs was performed by Fourier-transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), in vitro drug release, and drug loading efficiency (LE). 1, 2-Dimethylhydrazine (DMH) and dextran sulfate sodium (DSS) were applied to induce adenocarcinoma tumors on inbred male Wistar rats’ colon. The treatment group of rats was administered through enema with NPs dispersion. Hematoxylin and eosin staining were performed to the histopathological examination of tumors. Results: Zeta potential and particle size for NPs were +53.5 ± 5 mV and 179 ± 28 nm, respectively. About 96% Qu LE was obtained with a maximum release of 5.63 ±1.59% and 4.62 ± 1.33% after 24 hours in PB solution with pH values of 6 and 7.4, respectively. The numbers of 8 to 21 tumors were observed in all rats administered with DMH and DSS. Significantly decreasing of microvascular density and mitosis count was detected in the treatment group in comparison with cancerous group (P = 0.032 for the former compared to P = 0.016 for the later), respectively. Furthermore, the treatment group showed a high apoptosis rate (P = 0.038). Conclusion: The developed Qu-loaded CS NPs were good candidates for site-specific and sustained drug release in enema treatment. Decreasing of microvascular density and mitosis count, along with increasing the apoptosis percent in the treatment group proved that the NPs could have promising results in site-specific and sustained drug delivery against colorectal cancer. [ABSTRACT FROM AUTHOR]

The photo catalytic activity of ZnO-graphene (ZnO-G) nanocomposite and TiO2 nanoparticles physical mixtures for the enhanced degradation of reactive red dye 198 (RR198) under UVC light was evaluated and established. The photo catalytic results revealed that the RR198 was degraded at around 34.4% and 37.7% after 180 min of irradiation, respectively, in the presence of ZnO-G nanocomposite and TiO2 nanoparticles, solely. Interestingly, physical mixtures of both catalysts induced an enhanced catalytic activity comparing to the bare ones. The ideal mixing ratio was found to be 66:34 wt% (ZnO-G:TiO2) with 71.8% degradation performance after 180 min of irradiation. Moreover, the response surface methodology using the best mixture was employed to optimize and determine the interaction effects between three independent operational parameters which are photo catalyst dosage (0.4 – 0.025 mg), initial pH (3–11), and initial dye concentration (5 – 15 mg/L). Based on the results obtained, it was found that a maximum predicted degradation efficiency of RR 198 reached 99% was in agreement with the average of three experimental values (96%) under the following optimal conditions: 0.4 g mixture dose, initial pH of 3.8, and 5 mg/L initial dye concentration. This convergence between the predicted and experimental results indicates the validity of the model for predicting the maximum percentage degradation of RR198 under the above-mentioned optimum conditions. The ANOVA result indicated that the model is significant with the P value of 8.683 × 10–10 is less than 0.0001, which implies that the model terms are highly significant. Regression analysis with an R² value of 0.986 indicated a satisfactory correlation between the experimental data and predicted values. Additionally, non-toxic metabolites with respect to Daphnia Magna and high total organic carbon reduction after treatment with the mixture evidenced that this process can significantly decrease toxicity and mineralize the dye. Finally, the universal degradation ability of the photo catalysts mixture was evaluated and proven towards many model substrates. [ABSTRACT FROM AUTHOR]

The role of molecularly imprinted polymers (MIPs) is changing from academic to applied researches. Challenging problems about MIP will be more highlighted in applicable uses and solving these problems is vital. The controlled/"living" radical polymerization (CLRP) techniques are applicable to solve the challenging problems in MIPs. The "living" nature of CLRP helps to improve the heterogeneity of binding sites in MIPs as a main challenge where precise control over sizes, compositions, and surface functionalities is achieved. Among different techniques of CLRP, reversible addition-fragmentation chain transfer (RAFT) technique presents distinguished benefits such as compatibility and tolerance to a wide range of functional monomers and mild reaction conditions rather than other CLRP techniques. In this review, in order to obtain more insights into the potential benefits of RAFT polymerization in fabrication of nano and micro MIP networks, recent research in advanced MIP materials for different templates with improved morphology, efficiency, and binding capacities with respect to traditional free radical polymerization (FRP) will be discussed. MIPs prepared via RAFT method have advantages of MIPs as high performance molecular recognition devices and CLRP as controllable polymerization mechanism, simultaneously. [ABSTRACT FROM AUTHOR]

This study evaluates the in vitro antibacterial activity of three molecular weights of chitosan in the form of micro (CS) as well as nanoparticles (CSNPs). CSNPs were prepared using low (LWC), medium molecular weight (MWC) and middle-viscous crab shells chitosan (MVC). The antibacterial activities were evaluated through determination of IC 50 , minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) against Pseudomonas fluorescens , Erwinia carotovora and Escherichia coli . Experimental results showed that the antibacterial activity was significantly enhanced in the CSNPs comparison to CS microparticles, especially so for MVC nanoparticles (MVCN) in that the MIC values against all tested bacteria were ca. 50% those of the microparticles. Moreover, MWC and LWC nanoparticles showed lower MIC values compared with related microparticles only for P. fluorescens and E. coli , respectively. In addition, atomic force microscopy (AFM) of CSNPs-treated cultures of selected bacteria species revealed structural changes in the bacterial cell wall. The present study indicates that the antibacterial activity of CS varied depending on the molecular weight of CS micro and nanoparticles forms as well as on the particular bacterium. The selection of CS's molecular weight could be thought to be more dependent on its application. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nanoparticles were synthesized, characterized, and used for photocatalytic removal of amoxicilline and sulfamethoxazole from contaminated water. Microwave-assisted gel combustion synthesis method was optimized for type and amount of complexing agent and calcination temperature, in order to obtain the best photocatalytic activity. Characterization of ZnO nanoparticles according to their scanning electron microscopy and transmission electron microscopy images and X-ray diffraction pattern showed homogenous spherical nanoparticles with an average crystalline size of 25.82 nm. Effects of several operational factors such as pH of antibiotic solution, initial concentration of antibiotic, ZnO nanoparticles loading amount, and presence of NaCl salt or buffered solution were investigated. Results showed complete removal of antibiotic compounds in six hours using ZnO nanoparticles/UV-C irradiation. Mineralization of organic content were 62.8 and 20.8% for amoxicilline and sulfamethoxazole, respectively. Photocatalytic removal of both antibiotics followed the Langmuir–Hinshelwood model in the range of concentration of 5–20 mg L−1. ZnO nanoparticles were used for three subsequent runs without significant decrease in their photocatalytic activity. [ABSTRACT FROM PUBLISHER]

ZnO nanoparticles were manufactured using microwave-assisted combustion. The structural and morphological properties of the nanoparticles were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy, and Fourier transform infrared spectroscopy. Photocatalytic degradation of ortho-nitrophenol (O-NP) in aqueous solution using the synthesized nanoparticles was performed under UV–C irradiation and is reported for the first time. The effect of the initial O-NP concentration, amount of photocatalyst, pH, and salt was investigated during photodegradation. Analysis of the degraded samples using HPLC with UV detection revealed that photocatalysis in the presence of ZnO nanoparticles removed 98% of the O-NP in 5 h. In addition, the photocatalytic degradation kinetics of O-NP were studied, and the results suggest that the data are best fitted to pseudo-first-order kinetic and Langmuir–Hinshelwood models. [ABSTRACT FROM PUBLISHER]

MnFeO nanoparticles of various particle sizes were prepared by co-precipitation, in which different hydroxide concentrations were employed to control particle growth. X-ray diffraction and scanning electron microscopy were used to investigate the nanoparticle structure and morphology (shape and size). The particle size increased with increasing hydroxide concentration. The magnetization and coercivity field were measured by vibrating sample magnetometry. Changes in magnetic behavior were observed in the magnetic hysteresis loop curves of nanoparticles with increasing hydroxide concentration. In the absence of hydroxide, nanoparticles exhibited paramagnetic behavior. Increasing the hydroxide concentration caused a gradual conversion to ferrimagnetic behavior. An increased Néel temperature was observed with increasing hydroxide concentration, and the saturation magnetization exhibited a sharp decrease. Nonuniform hysteresis was observed in the magnetization curve for the sample prepared from hydroxide and ammonium. [ABSTRACT FROM AUTHOR]

MnFeO nanoparticles were prepared by a coprecipitation chemical method. The average size of the obtained nanoparticles was about 30 nm. The hysteresis measured at T=300 K clearly shows ferromagnetic order at room temperature while that measured at T=450 K shows superparamagnetic behavior. The difference in the magnetization curves in the field increasing cycle and field decreasing cycle at higher temperatures (450 K or higher) is very unusual. In this case, a hysteresis in magnetization in higher magnetic fields with an opening up of the magnetization curve was observed. In this work, the effect of temperature and time of application of the applied field on the magnetization behavior was studied. [ABSTRACT FROM AUTHOR]

We describe a modification of glassy carbon (GC) electrode surface with electrodeposited cobalt oxide nanoparticles (CoOx NPs), and then, this electrode is used to immobilization of Cytochrome c (Cyt c). The morphology of electrodeposited CoOx NPs was analyzed by scanning electron microscopy (SEM) and atomic force microscopy (AFM). Electrochemical redox property investigation of immobilized protein (Cyt c) molecules was accomplished by cyclic voltammetry (CV) technique. Cyt c/CoOx NPs/GC electrode exhibits electron transfer between the protein prosthetic groups and electrodeposited nanoparticles on the electrode surface and displayed a couple of stable redox peaks with a formal potential (E°) of −89.5 mV (107.5 mV vs. NHE) with respect to reference electrode in 0.05 M phosphate buffer solution (pH 7.0). The experimental results demonstrated that Cyt c/CoOx NPs/GC biosensor exhibited electrocatalytic activity toward the reduction of hydrogen peroxide and application to hydrogen peroxide determination was exemplified. [ABSTRACT FROM AUTHOR]

Abstract: In this study, horseradish peroxidase/nickel oxides nanoparticles/glassy carbon (HRP/NiO NPs/GC) electrode was prepared by first applying nickel oxides nanoparticles on glassy carbon surface and then horseradish peroxidase immobilized on the NiO NPs. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been used as a diagnostic tools to identify the synthesized NiO NPs. Immobilized HRP showed an electrochemical redox behavior pertained to HRP(Fe(III)–Fe(II)) by direct electron transfer between protein and nanoparticles with a formal potential (E 0′) of −55.5 mV (vs. Ag/AgCl and 141.5 mV vs. NHE) in 50 mM phosphate buffer solution (PBS). The anodic charge transfer coefficient (α) and heterogeneous electron transfer rate constant (k s) were 0.42 and 0.75 s−1, respectively. Biocatalytic activity of HRP/NiO NPs/GC electrode for reduction of hydrogen peroxide and application to hydrogen peroxide determination was exemplified. [Copyright &y& Elsevier]

• The Cinnamon essential oil encapsulated in chitosan nanoparticles. • Physical and antibacterial aspects of nanoencapsulated Cinnamon evidenced. • The most inhibition effect confirmed on Pseudomonas fluorescens. • The release of essential oil from chitosan nanoparticles exhibited Fickian behavior. • Lower release of Cinnamon compared to Zataria essential oil established. Widespread consumption of essential oils as green and efficient preservative is limited due to high instability and volatility of bioactive components. This work aimed to improve the antibacterial impact of Cinnamomum zeylanicum essential oil (CE) by encapsulating into chitosan nanoparticles (CHNPs) using an ionic gelation method against Escherichia coli , Erwinia carotovora, and Pseudomonas fluorescens. The success of CE encapsulation was confirmed by ultraviolet and visible spectroscopy. The size of the obtained nanoparticles was 100−200 nm in diameter. Nanoparticles yield was around 55–72 % w/w. In vitro release analysis also indicated a controlled and sustained release of CE, an initial explosion impact and pursued by a slow-core release. The measure of freed CE was 21.4, 26.8, and 31.65 % in buffer media at a pH of 7, 5, and 3 after 40 days respectively. Further, experimental results showed the superior performance of CE-loaded CHNPs in comparison with CHNPs and CE alone against tested bacteria. The CE when encapsulated by CHNPs, offered the highest antibacterial activity. Such nanoparticles may represent a delivery system that could enhance the antibacterial impact of CE. It was verified that P. fluorescens show more sensitivity than E. carotovora and E. coli to CE-loaded CHNPs. However, the maximum antibacterial activity of CHNPs was recorded against E. coli. In brief, chitosan nanoparticles-based delivery system could be introduced as a practical approach to improve the use of natural antimicrobial agents in the health and food industries. [ABSTRACT FROM AUTHOR]

In the present work, HZSM-5 zeolite nanoparticles were prepared under hydrothermal conditions by using n-butylamine, tetrapropylammonium bromide, and n-butylamine-tetrapropylammonium bromide mixture as a template. The obtained examples were intently characterized via N2 adsorption–desorption, ammonia temperature-programmed desorption (NH3-TPD), X-ray diffraction, and transmission electron microscopy (TEM) techniques. The acquired outcomes showed that using the mixture of templates caused to increase in the mesoporosity of HZSM-5 zeolite. Also, the particle size of the synthesized zeolites was reduced by applying the mixture of templates. Next, the prepared zeolites were used as a catalyst in the methanol to propylene (MTP) synthesis, and their activity was evaluated. The results indicated that the catalyst prepared from the mixture of templates had the lowest deactivation rate in the MTP process. These outcomes appeared that there is a straight connection between the deactivation and acidic properties of catalysts. [ABSTRACT FROM AUTHOR]

Abstract: A sensitive and selective electrochemical sensor was fabricated via the drop-casting of carbon nanoparticles (CNPs) suspension onto a glassy carbon electrode (GCE). The application of this sensor was investigated in simultaneous determination of acetaminophen (ACE) and tramadol (TRA) drugs in pharmaceutical dosage form and ACE determination in human plasma. In order to study the electrochemical behaviors of the drugs, cyclic and differential pulse voltammetric studies of ACE and TRA were carried out at the surfaces of the modified GCE (MGCE) and the bare GCE. The dependence of peak currents and potentials on pH, concentration and the potential scan rate were investigated for these compounds at the surface of MGCE. Atomic force microscopy (AFM) was used for the characterization of the film modifier and its morphology on the surface of GCE. The results of the electrochemical investigations showed that CNPs, via a thin layer model based on the diffusion within a porous layer, enhanced the electroactive surface area and caused a remarkable increase in the peak currents. The thin layer of the modifier showed a catalytic effect and accelerated the rate of the electron transfer process. Application of the MGCE resulted in a sensitivity enhancement and a considerable decrease in the anodic overpotential, leading to negative shifts in peak potentials. An optimum electrochemical response was obtained for the sensor in the buffered solution of pH 7.0 and using 2μL CNPs suspension cast on the surface of GCE. Using differential pulse voltammetry, the prepared sensor showed good sensitivity and selectivity for the determination of ACE and TRA in wide linear ranges of 0.1–100 and 10–1000μM, respectively. The resulted detection limits for ACE and TRA was 0.05 and 1μM, respectively. The CNPs modified GCE was successfully applied for ACE and TRA determinations in pharmaceutical dosage forms and also for the determination of ACE in human plasma. [Copyright &y& Elsevier]

Abstract: A new sensitive and selective electrochemical sensor was developed for determination of naltrexone (NAL) in pharmaceutical dosage form and human plasma. Naltrexone is an opioid antagonist which is commonly used for the treatment of narcotic addiction and alcohol dependence. A voltammetric study of naltrexone has been carried out at the surface of glassy carbon electrode (GCE) modified with Nafion-doped carbon nanoparticles (CNPs). The electrochemical oxidation of naltrexone was investigated by cyclic and differential pulse voltammetric techniques. The dependence of peak currents and potentials on pH, concentration and the potential scan rate was investigated. The electrode characterization by electrochemical methods and atomic force microscopy (AFM) showed that CNPs enhanced the electroactive surface area and accelerated the rate of electron transfer. Application of the modified electrode resulted in a sensitivity enhancement of more than 20 times, relative to the bare GCE, in detection of NAL and a considerable negative shift in peak potential was achieved. Two linear dynamic ranges of 1–10μM and 10–100μM with a detection limit of 0.1μM was obtained in phosphate buffer of pH=3. Differential pulse voltammetry as a simple, rapid, sensitive and selective method was developed for the determination of NAL in dosage form and human plasma without any treatments. No electroactive interferences were found in biological fluids from the endogenous substances and additives present in capsules. [Copyright &y& Elsevier]

A hybrid material of polyaniline (PAn)/anatase TiO2 nanoparticle was prepared by the potential cycling method within dispersed anatase TiO2 nanoparticles in solution. [Copyright &y& Elsevier]