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Abstract: Coronavirus disease (COVID-19) is an infectious disease caused by coronavirus. Developing specific drugs for inhibiting replication and viral entry is crucial. Several clinical trial studies are underway to evaluate the efficacy of anti-viral drugs for COVID-19 patients. Nanomedicine formulations can present a novel strategy for targeting the virus life cycle. Nano-drug delivery systems can modify the pharmacodynamics and pharmacokinetics properties of anti-viral drugs and reduce their adverse effects. Moreover, nanocarriers can directly exhibit anti-viral effects. A number of nanocarriers have been studied for this purpose, including liposomes, dendrimers, exosomes and decoy nanoparticles (NPs). Among them, decoy NPs have been considered more as nanodecoys can efficiently protect host cells from the infection of SARS-CoV-2. The aim of this review article is to highlight the probable nanomedicine therapeutic strategies to develop anti-viral drug delivery systems for the treatment of COVID-19.

An extended-release tablet of tacrolimus as once-daily dosing was fabricated using 3D printing technology. It was developed by combining two 3D-printing methods in parallel. Indeed, an optimized mixture of PVA, sorbitol, and magnesium stearate as a shell compartment was printed through a hot-melt extrusion (HME) nozzle while an HPMC gel mixture of the drug in the core compartment was printed by a pressure-assisted micro-syringe (PAM). A 3D-printed tablet with an infill of 90% was selected as an optimized formula upon the desired dissolution profile, releasing 86% of the drug at 12 h, similar to the commercial one. The weight variation, friability, hardness, assay, and content uniformity determination met USP requirements. A microbial evaluation showed that the 3D-printed tablet does not support microbial growth. SEM analysis showed smooth surfaces with multiple deposited layers. No peak interference appeared based on FTIR analysis. No decomposition of the polymer and drug was observed in the printing temperature, and no change in tacrolimus crystallinity was detected based on TGA and DSC analyses, respectively. The novel, sTable 3D-printed tablet, fabricated using controllable additive manufacturing, can quickly provide tailored dosing with specific kinetic release for personalized medicine at the point-of-care.

The bio/sensors performance has been established to be significantly affected through partially or entirely alignment of nano/microfibrous in polymeric mats. The matter of crystalline/amorphous proportion in semicrystalline polymers is another factor that can affect the application of the piezoelectric patches. The present work deals with fabricating the scaffolds of micro/nanofibers through a modified electrospinning procedure. The ratio of the relevant organic and polar solvents, the beading, the degree of fiber alignment, and fiber thickness have been intentionally elaborated. An unaligned unbeaded nanofibrous mat has been fabricated after tuning the solvents to poly-lactic acid ratio. This paper, for the first time, deals with the calculation of the value of d

Zoledronic acid (ZA) is known as a potent bisphosphonate in osteogenic differentiation, but at high doses, it possesses toxic effects and causes decreased proliferation and differentiation of osteoblasts. Therefore, encapsulation of ZA into nanoparticles and control of its release is expected to promote differentiation of stem cells into osteoblasts. The present work aimed to develop a simple method for synthesis of monodisperse ZA-loaded chitosan (CS) nanoparticles. In this regard, we proposed a microfluidic synthesis of nanoparticles through the ionic cross-linking of CS in the presence of ZA without a crosslinker. The main advantages of these microfluidic generated nanoparticles were narrow size distribution and fine spherical shape. Conversely, the nanoparticles that were synthesized using a bulk mixing method had an irregular shape with a broad size distribution. Real-time PCR assay as well as alizarin red staining were used to evaluate the in-vitro osteogenic potential of the nanoparticles. The results indicated that the controlled release of ZA from the microfluidic system generated uniform nanoparticles, improving the osteogenic differentiation of mesenchymal stem cells. Additionally, this microfluidic device provided the well-controlled synthesis of novel nanoparticles with a modified CS macromolecular polymer for targeted drug delivery systems.

Introduction Currently, gastroesophageal reflux disease (GERD) is one of the most ubiquitous problems in clinical practice. An antacid-alginate combination (under the trade name Gaviscon) is a natural-based product that effectively suppresses GERD. This product acts via the formation of viscous gel that floats on the top of the gastric content. On the other hand, efficient management of Helicobacter pylori infection with minimal side effects is an important goal for gastroenterologists. Furthermore, some H. pylori-positive patients suffer from GERD. Methods Here, we present the results of investigations on alginate conjugated to sugar codes in order to find initial clues regarding the potential ability of this conjugate in the simultaneous prophylaxis of GERD and H. pylori infection in an in vitro assay. Results It is noteworthy that our results reveal that sugar codes conjugated alginate considerably decrease (approximately 74%) the adhesion of H. pylori to gastric epithelial cells in vitro. Moreover, surprisingly after conjugation of sugar codes, alginate can maintain its ability to create gel. Our results demonstrate that alginate conjugated to sugar codes is not cytotoxic. Conclusion The preparation of these conjugates can be regarded as the first step to establish a new roadmap for the simultaneous prevention of GERD and H. pylori infection in future studies on in vivo models.

Silk worm (Bombyx Mori) protein, have been considered as potential materials for a variety of advanced engineering and biomedical applications for decades. Recently, silkworm silk has gained significant importance in research attention mainly because of its remarkable and exceptional mechanical properties. Silk has already been shown to have unique interactions with cells in tissues through bio-recognition units. The natural silk contains fibroin and sericin and has been used in various tissues of the human body (skin, bone, nerve, and so on). Besides, silk also still has anti-cancer, anti-tyrosinase, anti-coagulant, anti-oxidant, anti-bacterial, and anti-diabetic properties. This article is supposed to describe the diverse biomedical capabilities of Bombyx Mori silk as the appropriate biomaterial among the assorted natural and artificial polymers that are presently accessible, and ideal for usage in regenerative medicine fields. This article is protected by copyright. All rights reserved.

A novel series of benzylpyridinium-based benzoheterocycles (benzimidazole, benzoxazole or benzothiazole) were designed as potent acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) inhibitors. The title compounds 4a-q were conveniently synthesized via condensation reaction of 1,2-phenylenediamine, 2-aminophenol or 2-aminothiophenol with pyridin-4-carbalehyde, followed by N-benzylation using various benzyl halides. The results of in vitro biological assays revealed that most of them, especially 4c and 4g, had potent anticholinesterase activity comparable or more potent than reference drug, donepezil. The kinetic study demonstrated that the representative compound 4c inhibits AChE in competitive manner. According to the ligand-enzyme docking simulation, compound 4c occupied the active site at the vicinity of catalytic triad. The compounds 4c and 4g were found to be inhibitors of Aβ self-aggregation as well as AChE-induced Aβ aggregation. Meanwhile, these compounds could significantly protect PC12 cells against H2O2-induced injury and showed no toxicity against HepG2 cells. As multi-targeted structures, compounds 4c and 4g could be considered as promising candidate for further lead developments to treat Alzheimer's disease.

Articular cartilage has an avascular structure with a poor ability for self-repair; therefore, many challenges arise in cases of trauma or disease. It is of utmost importance to identify the proper biomaterial for tissue repair that has the capability to direct cell recruitment, proliferation, differentiation, and tissue integration by imitating the natural microenvironment of cells and transmitting an orchestra of intracellular signals. Cartilage extracellular matrix (cECM) is a complex nanostructure composed of divergent proteins and glycosaminoglycans (GAGs), which regulate many functions of resident cells. Numerous studies have shown the remarkable capacity of ECM-derived biomaterials for tissue repair and regeneration. Moreover, given the importance of biodegradability, biocompatibility, 3D structure, porosity, and mechanical stability in the design of suitable scaffolds for cartilage tissue engineering, demineralized bone matrix (DBM) appears to be a promising biomaterial for this purpose, as it possesses the aforementioned characteristics inherently. To the best of the authors' knowledge, no comprehensive review study on the use of DBM in cartilage tissue engineering has previously been published. Since so much work is needed to address DBM limitations such as pore size, cell retention, and so on, we decided to draw the attention of researchers in this field by compiling a list of recent publications. This review discusses the implementation of composite scaffolds of natural or synthetic origin functionalized with cECM or DBM in cartilage tissue engineering. Cutting-edge advances and limitations are also discussed in an attempt to provide guidance to researchers and clinicians.

Introduction Currently, gastroesophageal reflux disease (GERD) is one of the most ubiquitous problems in clinical practice. An antacid-alginate combination (under the trade name Gaviscon) is a natural-based product that effectively suppresses GERD. This product acts via the formation of viscous gel that floats on the top of the gastric content. On the other hand, efficient management of Helicobacter pylori infection with minimal side effects is an important goal for gastroenterologists. Furthermore, some H. pylori-positive patients suffer from GERD. Methods Here, we present the results of investigations on alginate conjugated to sugar codes in order to find initial clues regarding the potential ability of this conjugate in the simultaneous prophylaxis of GERD and H. pylori infection in an in vitro assay. Results It is noteworthy that our results reveal that sugar codes conjugated alginate considerably decrease (approximately 74%) the adhesion of H. pylori to gastric epithelial cells in vitro. Moreover, surprisingly after conjugation of sugar codes, alginate can maintain its ability to create gel. Our results demonstrate that alginate conjugated to sugar codes is not cytotoxic. Conclusion The preparation of these conjugates can be regarded as the first step to establish a new roadmap for the simultaneous prevention of GERD and H. pylori infection in future studies on in vivo models.

Despite the ease of the electrospinning process of synthetic polymers, the adjustment of several independent variables for natural ones is a complex procedure. In this work, the electrospinning par...

Theranostics with the ability to simultaneous monitoring of treatment progress and controlled delivery of therapeutic agents has become as an emerging therapeutic paradigm in cancer therapy. In this study, we have developed a novel surface functionalized iron oxide nanoparticle using polyethyleneimine and glutathione for targeted curcumin (CUR) delivery and acceptable pH sensitive character. The developed magnetic nanoparticles (MNPs) were physicochemically characterized by FT-IR, XRD, FE-SEM and TEM. The MNPs was obtained in spherical shape with diameter of 50 nm. CUR was efficiently loaded into the MNPs and then in vitro release analyses were evaluated and showed that the prepared MNPs could release higher amount of CUR in acidic medium compared to neutral medium due to the pH sensitive property of the coated polymer. MTT assay confirmed the superior toxicity of CUR loaded MNPs compared to the control nanoparticles. Higher cellular uptake of the MNPs than negative control cells was demonstrated in SK-N-MC cell line. In vitro assessment of MRI properties showed that synthesized MNPs could be used as MRI imaging agent. Furthermore, according to hemolysis assay, the developed formulation exhibited suitable hemocompatibility. In vivo blood circulation analysis of the MNPs also exhibited enhanced serum bioavailability up to 2.5 fold for CUR loaded MNPs compared with free CUR.

The electrospun biocompatible poly (e-caprolactonediol)-based polyurethane (PCL-Diol-b-PU) core/shell nanofibrous scaffolds were prepared via the coaxial electrospinning process. Temozolomi...

The peripheral nerve regeneration is still one of the major clinical problems, which has received a great deal of attention. In this study, the electrospun silk fibroin (SF)/poly(ethylene oxide) (PEO) nanofibrous scaffolds were fabricated and functionalized their surfaces with laminin (LN) without chemical linkers for potential use in the peripheral nerve tissue engineering. The morphology, surface chemistry, thermal behavior and wettability of the scaffolds were examined to evaluate their performance by means of scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and water contact angle (WCA) measurements, respectively. The proliferation and viability of Schwann cells onto the surfaces of SF/PEO nanofibrous scaffolds were investigated using SEM and thiazolyl blue (MTT) assay. The results showed an improvement of SF conformation and surface hydrophilicity of SF/PEO nanofibers after methanol and O2 plasma treatments. The immunostaining observation indicated a continuous coating of LN on the scaffolds. Improving the surface hydrophilicity and LN functionalization significantly increased the cell proliferation and this was more prominent after 5 days of culture time. In conclusion, the obtained results revealed that the electrospun LN-functionalized SF/PEO nanofibrous scaffold could be a promising candidate for peripheral nerve tissue regeneration. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 106B: 1595-1604, 2018.

In the present study, the anticancer drug temozolomide (TMZ) was initially loaded into the chitosan (CS) nanoparticles and synthesized CS/TMZ nanoparticles were incorporated into the synthesized poly (ε-caprolactone diol) based polyurethane (PCL-Diol-b-PU) nanofibers. The synthesized nanoparticles and nanofibers were characterized using dynamic light scattering, transmission electron microscopy, X-ray powder diffraction and scanning electron microscopy. The obtained results revealed that the CS/TMZ nanoparticles were successfully embedded into the PCL-Diol-b-PU nanofibers. The gold nanoparticles with average particle size of 18nm were synthesized and coated on the nanofibers surface to enhance the antitumor activity of CS/TMZ loaded nanofibers against inhibiting the growth of U-87 MG human glioblastoma cells. The sustained TMZ release for 30days with the zero order kinetic model were achieved from both CS/TMZ loaded PCL-Diol-b-PU and gold-coated nanofibers. The cell viability results indicated that the gold-coated nanofibers can effectively inhibit the growth of U-87 glioblastoma cells. Therefore, the prepared gold-coated CS/TMZ loaded PCL-Diol-b-PU nanofibers would be a potential candidate for glioblastoma cancer treatment.

In the present work, a reliable, rapid, and controllable method is developed for the continuous generation of pharmaceutical curcumin and loratadine nanoparticles (NPs). Micro droplets of curcumin ...

Context: Curcumin, a naturally occurring polyphenol, has been extensively studied for its broad-spectrum anticancer effects. The potential benefits are, however, limited due to its poor water solubility and rapid degradation which result in low bioavailability on administration. Objectives: This study encapsulates curcumin in nanoliposomes including an integrin-homing peptide combined with a C end R neuropilin-1 targeting motif for targeted delivery and receptor-mediated internalization, respectively. Materials and methods: The linear GHHNGR (Glycine–Histidine–Histidine–Asparagine–Glycine–Arginine) was synthesized through F-moc chemistry on 2-chlorotrityl chloride resin and conjugated to oleic acid. The lipoyl-peptide units were then co-assembled with lecithin and 0–75 mole % Tween-80 into liposomes. Curcumin was passively entrapped using a film hydration technique and its degradation profile was examined within seven consecutive days. The cytotoxic effects of the curcumin-loaded liposomes were studied on MCF-7 and MDA-MB-468, during 24 h exposure in MTT assay. Results: The maximum curcumin entrapment (15.5% W/W) and minimum degradation (

A series of 20 novel benzimidazole and benzothiazole derivatives linked to a 1,2,3-triazole ring system was synthesised, characterised and evaluated for in vitro acetylcholinesterase (AChE) inhibitory activity. Several copper catalysts and solvents were screened to establish the optimal conditions for the preparation of the target compounds. Three different linkers were used to optimise the enzyme inhibitory effect. Out of the 20 compounds, 13 showed some AChE inhibition. The most potent compound, which showed 84% inhibition at 100 μM, contained a 1-(2-fluorobenzyl)-1,2,3-triazole linked to a benzimidazole group. A docking simulation study showed that the most active compound bound preferentially to the catalytic anionic subsite of the AChE enzyme.

A highly dispersible and magnetically recoverable Cu-PEI@Fe$_{3}$O$_{4}$ MNPs catalyst was prepared and successfully applied in one-pot three-component coupling of terminal alkynes, sodium azide, and alkyl bromides/chlorides in water to give 1,4-disubstituted 1,2,3-triazoles with good to excellent yields. The catalyst was fully characterized with FT-IR, TGA, TEM, SEM, VSM, EDX, cyclic voltammetry, and ICP-AES spectroscopic techniques. Furthermore, the catalyst was easily recycled by an external magnet and successfully reused six times in the reaction without significant loss of its catalytic activity and copper leaching. The large-scale reaction was also carried out in the absence of any base and reducing agent even with 0.1 mol% of the catalyst in aqueous media, making this protocol a good candidate for practical applications.

Targeted nanoparticle platforms designed to induce cell death by apoptosis can bypass the resistance mechanisms of cancer cells. With this in mind we have constructed a new cancer-targeting peptide-functionalized nanoparticle using gold nanoparticles (AuNPs) and a thioctic acid–DMPGTVLP peptide (TA-peptide) conjugate. Morphological analysis of the nanoparticles by transmission electron microscopy showed average diameters of about 3.52 nm and 26.2 nm for the AuNP core and shell, respectively. Strong affinity toward the nucleolin receptors of breast cancer cell lines MCF-7 and T47D was observed for the TA-peptide gold nanoparticles (TAP@AuNPs) based on IC50 values. Furthermore, the nanoparticles showed excellent hemocompatibility. Quantitative results of atomic absorption showed improved uptake of TAP@AuNPs. Treatment of the cells with TAP@AuNPS resulted in greater release of cytochrome c following caspase-3/7 activation compared with free TA-peptide. The cytosolic level of adenosine triphosphate for TAP@AuNPs was higher than in controls. Higher anti-tumor efficiency was observed for TAP@AuNPs than TA-peptide compared with phosphate-buffered saline after intratumoral injection in tumor-bearing mice. It can be concluded that the design and development of a receptor-specific peptide-AuNP platform will be valuable for theranostic applications in cancer nanomedicine.

Theranostics with the ability to simultaneous monitoring of treatment progress and controlled delivery of therapeutic agents has become as an emerging therapeutic paradigm in cancer therapy. In this study, we have developed a novel surface functionalized iron oxide nanoparticle using polyethyleneimine and glutathione for targeted curcumin (CUR) delivery and acceptable pH sensitive character. The developed magnetic nanoparticles (MNPs) were physicochemically characterized by FT-IR, XRD, FE-SEM and TEM. The MNPs was obtained in spherical shape with diameter of 50 nm. CUR was efficiently loaded into the MNPs and then in vitro release analyses were evaluated and showed that the prepared MNPs could release higher amount of CUR in acidic medium compared to neutral medium due to the pH sensitive property of the coated polymer. MTT assay confirmed the superior toxicity of CUR loaded MNPs compared to the control nanoparticles. Higher cellular uptake of the MNPs than negative control cells was demonstrated in SK-N-MC cell line. In vitro assessment of MRI properties showed that synthesized MNPs could be used as MRI imaging agent. Furthermore, according to hemolysis assay, the developed formulation exhibited suitable hemocompatibility. In vivo blood circulation analysis of the MNPs also exhibited enhanced serum bioavailability up to 2.5 fold for CUR loaded MNPs compared with free CUR.

© 2017 Elsevier B.V. Brain tumor is a lethal, fast growing cancer and a difficult case for treatment. Receptor-mediated endocytosis has been recognized as one of the most effective methods for drug delivery to brain tissue by overcoming obstacles associated with conventional therapeutics. In this work, a targeted theranostic drug delivery system (DDS) was prepared based on gold‑iron oxide nanocomposites (Fe3O4@Au NCs). Lipoic acid-curcumin (LA-CUR) was synthesized and introduced as a novel anticancer drug, and glutathione (GSH) was exploited as the targeting ligand. Both LA-CUR and GSH were easily attached to Fe3O4@Au NCs via Au-S interaction. As a negatively charged nanocarrier, the prepared DDS showed relatively less protein adsorption. Accordingly, hemocompatibility assays (complement, platelet, and leucocyte activation) revealed its hemocompatible virtue, especially in respect of free LA-CUR. GSH functionalization led to 2-fold increase of cellular uptake in GSH receptor-positive astrocyte cells which could primarily indicate the probable ability of the DDS to bypass BBB. Cytotoxicity and apoptosis assays together showed the noticeably enhanced cytotoxicity of LA-CUR against cancerous U87MG cells (IC50 = 2.69 μg/ml) in comparison with curcumin (IC50 = 21.31 μg/ml); moreover, the DDS demonstrated relatively higher cytotoxicity against cancerous U87MG cells than normal astrocyte cells which was in accordance with pH sensitive mechanism of LA-CUR release. Besides, the results of in vitro magnetic resonance imaging (MRI) (relaxation rate (r2) = 80.73 (s− 1·mM− 1)) primarily revealed that the DDS can be applied as a negative MRI contrast agent. In sum, the prepared DDS appeared to be a promising candidate for brain cancer treatment and a favorable MRI contrast agent.

Biodegradable polyethylene oxide (PEO)/chitosan (CS)/poly(e-caprolactone) (PCL)/olive oil composite nanofibers were fabricated by electrospinning process. The prepared nanofibers were characterized using SEM and FTIR analysis. A response surface methodology based on Box-Behnken design (BBD) was used to predict the average diameter of electrospun nanofibers based on electrospinning parameters including voltage, flow rate and tip-collector distance. The optimum experimental average diameter of electrospun nanofibers was found to be 86 nm which was in good agreement with the predicted value by the BBD analysis (88 nm). In vitro release of olive oil incorporated PEO/CS/PCL/olive oil nanofibers demonstrated a rapid release of olive oil during the first 3 h which enhanced gradually afterwards. Good attachment, spreading, cell proliferation, as well as nontoxic behavior of PEO/CS/PCL/olive oil nanofibrous scaffolds on HDF fibroblast cells were proved by cytotoxicity studies. Furthermore, the high antibacterial activity of PEO/CS/PCL/olive oil composite nanofibers against Gram-negative bacteria E. coli and Gram-positive S. aureus was observed. This study suggests that the prepared PEO/CS/PCL/olive oil composite nanofibrous scaffolds could be used as an ideal patch for wound dressing applications.

The coupling of adsorption and photo-Fenton processes has been studied for the simultaneous removal of phenol and paracetamol from aqueous systems. Photo-Fenton process exhibited the complete elimination of phenol and paracetamol during 1 h. For mineralization of contact time, the adsorption process was combined to the photo-Fenton process. The both NaX nanozeolites and cobalt ferrite nanoparticles were synthesized by microwave heating method and were used through the adsorption and photo-Fenton processes, respectively. The nanoparticles were characterized by XRD and SEM analysis. The Box–Behnken design was applied to evaluate the effect of key parameters including pH (3–4), phenol initial concentration (20–100 mg L−1), paracetamol initial concentration (20–100 mg L−1) and NaX to cobalt ferrite nanoparticles ratio (0.5–1.5) on the simultaneous removal of phenol and paracetamol at contact time of 30 min. By optimization of parameters, the removal percentages of phenol and paracetamol were found to be 99.95% and 99.80%, respectively. The results demonstrate that the coupling of adsorption and photo-Fenton processes is an alternative method to eliminate the phenolic compounds from wastewaters.

In the present study, the photo-Fenton process was applied for the treatment of phenol and paracetamol in a binary system. The cobalt ferrite nanoparticles synthesized by microwave heating method were applied during photo-Fenton process. The nanoparticles were characterized by XRD and SEM analysis. The response surface methodology based on Box–Behnken design was used to evaluate and optimize the interactive effects of five operating variables including pH, initial concentrations of phenol and paracetamol, H 2 O 2 concentration and cobalt nanoferrite dosage on the phenol and paracetamol degradation rates in photo-Fenton process. The results of experimental design indicated that the pH of 3.5, H 2 O 2 concentration of 50 mmol/L and cobalt nanoferrite dosage of 0.2 g/L maximize the efficiency of phenol and paracetamol degradation rates at the time in photo-Fenton process. The maximum experimental phenol and paracetamol degradation efficiencies for initial concentrations of 20 mg/L of phenol and paracetamol were found to be 95 and 85%, respectively. These values were in good agreement with the estimated values by the model in optimum conditions (94.5 and 84.4% for phenol and paracetamol degradation efficiencies). The obtained results demonstrated an excellent ability of synthesized cobalt ferrite nanoparticles to remove the phenolic compounds in photo-Fenton process.

In the present study, adsorption and photo-Fenton processes have been compared for the removal of phenol and paracetamol from aqueous solutions in a single and binary systems. NaX nanozeolites and cobalt ferrite nanoparticles were used during adsorption and photo-Fenton processes, respectively. Both nanoparticles were synthesized using microwave heating method. The synthesized nanoparticles were characterized using powder X-ray diffraction (XRD) and scanning electronic microscopy (SEM) analysis. Based on results, more than 99% removing percentages of phenol and paracetamol were obtained during photo-Fenton process at initial concentrations of 10, 20, 50, 100 and 200 mg/L of phenol and paracetamol. Moreover, the complete removing of phenol and paracetamol was only achieved at lower initial concentrations than 10 mg/L for phenol and paracetamol during adsorption process. The results showed a significant dependence of the phenol and paracetamol removing on the initial concentrations of phenol and paracetamol for selection of process. The photo-Fenton process could be considered an alternative method in higher initial concentrations of phenol and paracetamol. However, the adsorption process due to economical issue was preferred for phenol and paracetamol removing at lower initial concentrations. The kinetic data of photo-Fenton and adsorption processes were well described using first-order and pseudo-second-order kinetic models. The results of phenol and paracetamol removing in a binary system confirmed the obtained results of single removing of phenol and paracetamol in selection of process.

Biocompatible multi-layer iron oxide magnetic nanoparticles (MNPs) for drug delivery applications with increased loading capacity, sustained sensitive release profile, and high inherent magnetic properties as well as improved cellular uptake were prepared. In this approach, Fe3O4 MNPs were obtained by a co-precipitation method and functionalized using hydroxyapatite (HAP) and/or polyethyleneimine (PEI). They were then modified with β-cyclodextrin (CD) to increase their loading capacity. These MNPs allowed suitable encapsulation of hydrophobic curcumin (CUR) in the CD shell and CUR adsorption into the polymeric layers. The dissolution profile of CUR showed pH sensitive release of CUR. The protein corona pattern of the MNPs by electrophoresis showed lower protein adsorption for CD modified MNPs than for other MNPs. No significant toxicity was observed for the target MNPs, whereas the CUR loaded MNPs inhibited MCF-7 breast cancer cells more efficiently than free CUR. Moreover, the negligible hemolytic activity of the target MNPs showed their excellent haemocompatibility for cancer treatment. The preferential uptake of the drug by MCF-7 cells was observed for CUR loaded MNPs in comparison with free CUR using flow cytometric analysis. As a result, the designed and prepared MNPs can be considered to be a promising CUR delivery platform.

A novel electrospun chitosan/graphene oxide (GO) nanofibrous adsorbent was successfully developed by an electrospinning process. The adsorption behaviors of Cu2+, Pb2+ and Cr6+ metal ions from aqueous solutions using chitosan/GO nanofibers were investigated. The composite nanofibers were characterized by FTIR and SEM and TEM analysis. Kinetic and equilibrium studies showed that the experimental data of Cu2+, Pb2+ and Cr6+ were best described by double-exponential kinetic and Redlich–Peterson isotherm models. The maximum monolayer adsorption capacity of Pb2+, Cu2+and Cr6+ metal ions using chitosan/GO nanofibers was found to be 461.3, 423.8 and 310.4 mg g−1 at an equilibrium time of 30 min and temperature of 45 °C. Evaluation of the thermodynamic parameters (ΔG° 0 and ΔS° > 0) showed that the nature of the metal ions sorption by chitosan/GO nanofibers was endothermic and spontaneous. The reusability studies indicated that the chitosan/GO nanofibers could be reused frequently without almost any significant loss in adsorption performance. This study provides a promising chitosan/GO nanofibrous adsorbent with an efficient adsorption property for heavy metal ions removal.

In the present study, the potential of synthesized cobalt ferrite nanoparticles using microwave (M-CF) and conventional hydrothermal (H-CF) methods for degradation of phenol was investigated during photo-Fenton-like process. The synthesized nanoparticles were characterized using powder X-ray diffraction, scanning electronic microscopy, and vibrating sample magnetometer analysis. The results showed that the microwave heating method produced smaller size nanoparticles with relatively narrower particle size distribution as well as stronger magnetic properties, compared with H-CF nanoparticles. The effect of photo-Fenton-like process parameters including UV light intensity (0–75 W), catalyst dosage (0–0.5 g/L), pH (2–5), hydrogen peroxide concentration (0–100 mmol/L), phenol initial concentration (20–500 mg/L), and temperature (35–55°C) on the phenol degradation was investigated. The kinetic data of phenol degradation using both synthesized nanoparticles were well fitted by pseudo-first-order kinetic ...

Objective To to compare the chitosan/alginate, chitosan and alginate nanoparticles as plasmid vectors, to determine the morphological characteristics, size and physicochemical properties of nanoparticle-pEGFP complexes and to evaluate the potential of these nanoparticles in transfection of pEGFP plasmid in to a cultured the human embryonic kidney cell line (HEK 293 cells). Methods Nanoparticles comprising chitosan, alginate and both chitosan-alginate polymers were formed through pregel preparation method. The ability of plasmid-complexes in preventing DNA migration were assessed by the agarose gel assay. The efficiency of nanoparticles in transfection of pEGFP plasmid in the cultured HEK 293 cells was measured by flow cytometry. The effect of the nanoparticle-plasmid complexes on the cell viability was determined using cytotoxicity assay. Resutls Chitosan, alginate and alginate/chitosan nanoparticles had a mean Z-average diameter of 620 nm, 235.8 nm and 161.8 nm and mean zeta potential of 45 mV, −18.6 mV and 29.3 mV, respectively. Chitosan and chitosan/alginate nanoparticles have greater capacity to maintain plasmid than alginate nanoparticles. Alginate nanoparticles had the greater transfection in comparison to the others. Cell viability assays indicated that nanoparticles had no toxic effect on HEK 293 cells after 4 h or 24 h. Conclusions The combination of particle surface, hydrophobicity size and zeta potential can influence on transfection efficiency and the cellular uptake of the nanoparticles. Our suitable candidate for gene delivery would be alginate/chitosan nanoparticles.

Biocompatible and pH-sensitive poly (N-isopropylacrylamide-co-methacrylic acide-co-vinylpyrrolidone) [P(NIPAAm-MAA-VP)] nanofibers were prepared as a delivery vehicle for sustained release of doxorubicin hydrochloride (DOX) as an anticancer drug. The structure and morphology of nanofibers were investigated by SEM, FTIR, and XRD. P(NIPAAm-MAA-VP)–DOX complex was formed at pH 7 because of ionic interactions between DOX and polymers. P (NIPAAm-MAA-VP) nanofibers tailored to desire diameters with bead free morphology by optimizing the electrospinning parameters DOX release from P (NIPAAm-MAA-VP)/DOX complex was investigated as a biological on–off switch for the design of an intelligent drug delivery system triggered by external pH changes.

The aim of this study is to investigate the effect of thermomechanical treatment on the superelastic behavior of a Ti-50.5 at.%Ni wire in terms of loading/unloading plateau, mechanical hysteresis, and permanent set to optimize these parameters for orthodontic applications. A new three-point bending fixture, oral cavity configuration three-point bending (OCTPB) test, was utilized to determine the superelastic property in clinical condition, and therefore, the tests were carried out at 37 °C. The results indicate that the thermomechanical treatment is crucial for thermal transformation and mechanically induced transformation characteristics of the wire. Annealing of thermomechanically treated specimens at 300 and 400 °C for 1/2 and 1 h leads to good superelasticity for orthodontic applications. However, the best superelasticity at body temperature is obtained after annealing at 300 °C for 1/2 h with regard to low and constant unloading force and minimum permanent set.

In the present study, the temozolomide (TMZ) loaded poly (e-caprolactonediol) based polyurethane (PCL-Diol-b-PU) nanofibers were fabricated as local delivery systems against glioblastoma. The structure and morphology of nanofibers were characterized using FTIR and SEM analysis. The gold nanoparticles were coated on the nanofibers surface to enhance the efficacy of nanofibers for local chemotherapy of brain tumors. The effect of various ratios of DMF/THF solvents and solution concentration on the morphology and fiber diameter of PCL-Diol-b-PU nanofibers was investigated. The small burst release of TMZ with sustained TMZ release from both PCL-Diol-b-PU and gold-coated PCL-Diol-b-PU nanofibers were achieved over 30days. The Korsmayer-Peppas kinetic and Fickian diffusion models were used to describe the mechanism of TMZ release from nanofibers. The in vitro cell viability results revealed that the higher antitumor activity of synthesized nanofibers against glioblastoma cells compared with pristine TMZ. It was concluded that the prepared nanofibrous implants showed a higher potential in the local chemotherapy of brain tumors.

Two series of novel coumarin derivatives, substituted at 3 and 7 positions with aminoalkoxy groups, are synthesized, characterized, and screened. The effect of amine substituents and the length of cross-linker are investigated in acetyl- and butyrylcholinesterase (AChE and BuChE) inhibition. Target compounds show moderate to potent inhibitory activities against AChE and BuChE. 3-(3,4-Dichlorophenyl)-7-[4-(diethylamino)butoxy]-2H-chromen-2-one (4y) is identified as the most potent compound against AChE (IC50 =0.27 μm). Kinetic and molecular modeling studies affirmed that compound 4y works in a mixed-type way and interacts simultaneously with the catalytic active site (CAS) and peripheral anionic site (PAS) of AChE. In addition, compound 4y blocks β-amyloid (Aβ) self-aggregation with a ratio of 44.11 % at 100 μm and significantly protects PC12 cells from H2 O2 -damage in a dose-dependent manner.