Electrospun sandwich-structured of polycaprolactone/gelatin-based nanofibers with controlled release of ceftazidime for wound dressing.

In the present work, sandwich-like polycaprolactone/gelatin/polycaprolactone electrospun multilayered mats were implemented to control the release of ceftazidime (CTZ). The outer layers were made from polycaprolactone nanofibers (NFs), and CTZ-loaded gelatin provided an internal layer. The release profile of CTZ from mats was compared with monolayer gelatin mats and chemically cross-linked GEL mats. All the constructs were characterized using scanning electron microscopy (SEM), mechanical properties, viscosity, electrical conductivity, X-ray diffraction (XRD), and Fourier transform-infrared spectroscopy (FT-IR). In vitro cytotoxicity against normal fibroblasts as well as antibacterial activity of CTZ-loaded sandwich-like NFs were investigated by the MTT assay. The results showed that the drug release rate from the polycaprolactone/gelatin/polycaprolactone mat was slower than that of gelatin monolayer NFs, and the rate of release can be adjusted by changing the thickness of hydrophobic layers. The NFs exhibited high activity against Pseudomonas aeruginosa and Staphylococcus aureus, while no significant cytotoxicity was observed against human normal cells. Altogether, the final mat as a predominant antibacterial scaffold can be used for controlled drug release of antibacterial drugs as the wound healing dressings in tissue engineering.

The role of quercetin in the formation of titanium dioxide nanoparticles for nanomedical applications.

The current work aimed to synthesize and characterize titanium dioxide nanoparticles (TiO2NPs) using quercetin (QE) and evaluate their biological activities, i.e., anti-hemolytic, anti-inflammatory, and cytotoxicity effects. The crystallographic phase and morphology of biosynthesized QE-TiO2NPs were characterized by XRD (X-Ray Diffraction) and TEM/FE-SEM (Transmission/Field-Emission Scanning Electron Microscopy) micrographs. Functional groups involved in the synthesis process were determined by FTIR spectroscopy (Fourier Transform-Infrared Spectroscopy). Based on the characterization results, selected QE-TiO2NPs showed a rutile phase, spherical shape, and a size range of 7.3-39 nm. The QE-TiO2NPs did not show a hemolytic effect. They indicated 95.3% red blood cells (RBCs) membrane stabilization activity and 82.6% inhibition of bovine serum albumin (BSA) denaturation, similar to a standard drug, which proved their anti-inflammatory effects. The attained results from cytotoxicity studies revealed the toxic effects of QE-TiO2NPs with IC50 values below 100 and 50 µg/mL for human breast cancer cells of MCF-7 and melanoma cancer cells of A375, respectively. These NPs did not significantly affect normal skin fibroblast cells up to 50 µg/mL and only showed a 16% inhibition rate on the cell viability at 100 µg/mL. These NPs also induced excessive ROS generation. This work established the blood/biocompatibility and excellent nanomedical applications of biosynthesized QE-TiO2NPs.

Point-of-care vertical flow immunoassay system for ultra-sensitive multiplex biothreat-agent detection in biological fluids.

This paper presents simple, fast, and sensitive detection of multiple biothreat agents by paper-based vertical flow colorimetric sandwich immunoassay for detection of Yersinia pestis (LcrV and F1) and Francisella tularensis (lipopolysaccharide; LPS) antigens using a vertical flow immunoassay (VFI) prototype with portable syringe pump and a new membrane holder. The capture antibody (cAb) printing onto nitrocellulose membrane and gold-labelled detection antibody (dAb) were optimized to enhance the assay sensitivity and specificity. Even though the paper pore size was relaxed from previous 0.1 µm to the current 0.45 µm for serum samples, detection limits as low as 0.050 ng/mL for LcrV and F1, and 0.100 ng/mL for FtLPS have been achieved in buffer and similarly in diluted serum (with LcrV and F1 LODs remained the same and LPS LOD reduced to 0.250 ng/mL). These were 40, 80, and 50X (20X for LPS in serum) better than those from lateral flow configuration. Furthermore, the comparison of multiplex format demonstrated low cross-reactivity and equal sensitivity to that of the singleplex assay. The optimized VFI platform thus provides a portable and rapid on-site monitoring system for multiplex biothreat detection with the potential for high sensitivity, specificity, reproducibility, and multiplexing capability, supporting its utility in remote and resource-limited settings.

Recent advances in electrochemical strategies for bacteria detection.

Introduction: Bacterial infections have always been a major threat to public health and humans' life, and fast detection of bacteria in various samples is significant to provide early and effective treatments. Cell-culture protocols, as well-established methods, involve labor-intensive and complicated preparation steps. For overcoming this drawback, electrochemical methods may provide promising alternative tools for fast and reliable detection of bacterial infections. Methods: Therefore, this review study was done to present an overview of different electrochemical strategy based on recognition elements for detection of bacteria in the studies published during 2015-2020. For this purpose, many references in the field were reviewed, and the review covered several issues, including (a) enzymes, (b) receptors, (c) antimicrobial peptides, (d) lectins, (e) redox-active metabolites, (f) aptamer, (g) bacteriophage, (h) antibody, and (i) molecularly imprinted polymers. Results: Different analytical methods have developed are used to bacteria detection. However, most of these methods are highly time, and cost consuming, requiring trained personnel to perform the analysis. Among of these methods, electrochemical based methods are well accepted powerful tools for the detection of various analytes due to the inherent properties. Electrochemical sensors with different recognition elements can be used to design diagnostic system for bacterial infections. Recent studies have shown that electrochemical assay can provide promising reliable method for detection of bacteria. Conclusion: In general, the field of bacterial detection by electrochemical sensors is continuously growing. It is believed that this field will focus on portable devices for detection of bacteria based on electrochemical methods. Development of these devices requires close collaboration of various disciplines, such as biology, electrochemistry, and biomaterial engineering.

Optimization of Quercetin-Assisted Silver Nanoparticles Synthesis and Evaluation of Their Hemocompatibility, Antioxidant, Anti-Inflammatory, and Antibacterial effects.

In the present study, different effective parameters (temperature, reaction time, and pH) on the synthesis of quercetin-assisted silver nanoparticles (QE-AgNPs) are optimized. These biogenic NPs are characterized by different physico-chemical analyses, including transmission electron microscopy, X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy, and UV-visible spectroscopy. In addition, the biological properties of QE-AgNPs are evaluated through antioxidant, antimicrobial, anti-inflammatory, hemolysis, and coagulation time assays. The formation of QE-AgNPs is affected by different parameters. The optimum condition for the synthesis of QE-AgNPs is attained at 70 °C and pH 7. Prepared QE-AgNPs show a spherical shape with a crystalline nature and an average particle size of 20 ± 3.6 nm. The role of QE as a reducing and capping agent in the preparation process of QE-AgNPs is demonstrated using FTIR analysis. These NPs with excellent antioxidant activity (82.3% at a concentration of 400 µg mL-1) and anti-inflammatory properties (82.5% and 100% at concentrations of 37.25 and 500 µg mL-1, respectively), show good antimicrobial effects, particularly against Staphylococcus aureus. Furthermore, the results of the hemolytic and coagulation assay of QE-AgNPs indicate their hemo-compatibility. Therefore, hemo/bio-compatible QE-AgNPs with excellent and unique properties can be employed in different medicinal and pharmacological applications.

COVID-19 Infection and Mortality Rates within Medical Specialists and General Practitioners and Its Comparison with the General Population: A Longitudinal Nationwide Study.

BACKGROUND: We aimed to provide data regarding COVID-19 infection and mortality rates within different specialties of physicians and general medical practitioners in a longitudinal nationwide study and to compare the results with general population. METHODS: Data on COVID-19 infection and mortality of medical physicians in Iran was actively gathered through the Iranian Medical Council (IRIMC). Population COVID-19 cumulative incidence and mortality data were extracted from WHO situation analysis reports and data on Iranian population were obtained from the Statistical Center of Iran. RESULTS: As of Jul 27th 2020, COVID-19 infection and mortality rates were 0.680% and 0.0396% among 131223 physicians. The highest cumulative infection rates as of 27th July 2020, were observed in specialists of infectious diseases (3.14%) followed by neurology (2.18%), and internal medicine (2.13%). The highest cumulative mortality rates as of Nov 3rd 2020 were observed in specialties of forensic medicine (0.314%), anesthesiology (0.277%), urology (0.237%), and infectious diseases (0.20%). Male physicians comprised 95% of cumulative mortality as of Nov 3rd. The physicians' COVID-19 mortality in July and November were 49% and 23% higher than the general population respectively. CONCLUSION: Infection and mortality rates in Iranian physicians were higher than the general population, however the magnitude of difference was narrowing in longitudinal investigation. Provision of personnel protective equipment should be prioritized to specialists of infectious diseases, forensic medicine, anesthesiology, internal and emergency medicine, and urology.

Survival and Proliferation under Severely Hypoxic Microenvironments Using Cell-Laden Oxygenating Hydrogels.

Different strategies have been employed to provide adequate nutrients for engineered living tissues. These have mainly revolved around providing oxygen to alleviate the effects of chronic hypoxia or anoxia that result in necrosis or weak neovascularization, leading to failure of artificial tissue implants and hence poor clinical outcome. While different biomaterials have been used as oxygen generators for in vitro as well as in vivo applications, certain problems have hampered their wide application. Among these are the generation and the rate at which oxygen is produced together with the production of the reaction intermediates in the form of reactive oxygen species (ROS). Both these factors can be detrimental for cell survival and can severely affect the outcome of such studies. Here we present calcium peroxide (CPO) encapsulated in polycaprolactone as oxygen releasing microparticles (OMPs). While CPO releases oxygen upon hydrolysis, PCL encapsulation ensures that hydrolysis takes place slowly, thereby sustaining prolonged release of oxygen without the stress the bulk release can endow on the encapsulated cells. We used gelatin methacryloyl (GelMA) hydrogels containing these OMPs to stimulate survival and proliferation of encapsulated skeletal myoblasts and optimized the OMP concentration for sustained oxygen delivery over more than a week. The oxygen releasing and delivery platform described in this study opens up opportunities for cell-based therapeutic approaches to treat diseases resulting from ischemic conditions and enhance survival of implants under severe hypoxic conditions for successful clinical translation.

Surface modification of neurotrophin-3 loaded PCL/chitosan nanofiber/net by alginate hydrogel microlayer for enhanced biocompatibility in neural tissue engineering.

This study prepared a novel three-dimensional nanocomposite scaffold by the surface modification of PCL/chitosan nanofiber/net with alginate hydrogel microlayer, hoping to have the privilege of both nanofibers and hydrogels simultaneously. Bead free randomly oriented nanofiber/net (NFN) structure composed of chitosan and polycaprolactone (PCL) was fabricated by electrospinning method. The low surface roughness, good hydrophilicity, and high porosity were obtained from the NFN structure. Then, the PCL/chitosan nanofiber/net was coated with a microlayer of alginate containing neurotrophin-3 (NT-3) and conjunctiva mesenchymal stem cells (CJMSCs) as a new stem cell source. According to the cross-sectional FESEM, the scaffold shows a two-layer structure with interconnected pores in the range of 20 µm diameter. The finding revealed that the surface modification of nanofiber/net by alginate hydrogel microlayer caused lower inflammatory response and higher proliferation of CJMSCs than the unmodified scaffold. The initial burst release of NT-3 was 69% in 3 days which followed by a sustained release up to 21 days. The RT-PCR analysis showed that the expression of Nestin, MAP-2, and ß-tubulin III genes were increased 6, 5.4, and 8.8-fold, respectively. The results revealed that the surface-modified biomimetic scaffold possesses enhanced biocompatibility and could successfully differentiate CJMSCs to the neuron-like cells.

A Simple Method for Developing a Hand-Drawn Paper-Based Sensor for Mercury; Using Green Synthesized Silver Nanoparticles and Smartphone as a Hand-Held-Device for Colorimetric Assay.

Mercury ions are highly toxic at trace levels, and its pollution has posed a significant threat to the environment and public health, where current detection methods mainly require laborious operation and expensive instrumentation. Herein, a simple, cost-effective, instrument-free approach for selective detection of Hg2+ based on a hand-drawn paper-based naked-eye colorimetric device is developed. To develop a hand-drawn paper-based device, a crayon is used to build hydrophobic barriers and a paper puncher is applied to obtain patterns as a sensing zone. A green method for the synthesis of silver nanoparticles (AgNPs) is applied using Achillea Wilhelmsii (Aw) extract. The sensing ability of Aw-AgNPs toward Hg2+ is investigated in both solution-phase and paper substrate loaded with Aw-AgNPs using colorimetric methods. For the paper-based sensor, the quantification of the target relies on the visual readout of a color-changed sensing zone modified with Aw-AgNPs. Under optimal conditions, the color of Aw-AgNPs in aqueous solution and on the coated paper substrate can change from brown to colorless upon addition of target, with a detection limit of 28 × 10-9 m and 0.30 × 10-6 m, respectively. In conclusion, the present study indicates the potential of this hand-drawn eco-friendly paper-based sensor for monitoring of mercury.

Characterization and optimization of de-esterified Tragacanth-chitosan nanocomposite as a potential carrier for oral delivery of insulin: In vitro and ex vivo studies.

Oral administration of insulin is one of the most challenging topics within this area, because insulin is degraded in stomach before it enters the bloodstream. In this study, for the first time, a nano-carrier for controlled and targeted oral delivery of insulin was developed using de-esterified Tragacanth and chitosan. The fabricated nanoparticles were synthesized using coacervation technique and their properties were optimized using response surface methodology. The effect of experimental variables on the particle size and loading efficiency was examined. In addition, the interactions between components were analyzed using Fourier transform infrared. The thermal stability of nanoparticles was studied by thermal gravimetric analysis. The insulin loading efficiency was measured and in vitro release profile and ex vivo insulin permeability was determined. Optimized nanoparticles showed spherical shape with a size less than 200 nm and zeta potential of +17 mV. Owing to their nanoscale dimensions and mucoadhesiveness, nanoparticles were synthesized using medium molecular weight of Chitosan. The insulin loading efficacy for the system was 6.4%, released under simulated gastrointestinal conditions in a pH-dependent manner. Based on all of the obtained results, it can be concluded that these nanoparticles can potentially be utilized as a carrier for the oral insulin delivery.

Preparation, Physicochemical Characterization and Anti-Fungal Evaluation of Amphotericin B-Loaded PLGA-PEG-Galactosamine Nanoparticles.

Purpose: The present study aimed to formulate PLGA and PLGA-PEG-galactosamine nanoparticles (NPs) loaded with amphotericin B with appropriate physicochemical properties and antifungal activity. PLGA was functionalized with GalN to increase the adhesion and antifungal activity of NPs against Candida albicans. Methods: The physicochemical properties of NPs were characterized by particle size determination, zeta potential, drug crystallinity, loading efficiency, dissolution studies, differential scanning calorimeter (DSC), X-ray powder diffraction (XRPD), and Fourier transform infrared (FT-IR). Antifungal activity of the NPs at different drug/polymer ratios was examined by determining minimum inhibitory concentrations (MICs). Results: the FT-IR and 1 HNMR analysis successfully confirmed the formation of PLGA- PEG-GalN NPs. The PLGA NPs were in the size range of 174.1 ± 3.49 to 238.2±7.59 nm while PLGA-GalN NPs were 255.6 ±4.08 nm in size , respectively. Loading efficiency was in the range of 67%±2.4 to 77%±1.6, and entrapment efficiency in the range of 68.185%±1.9 to 73.05%±0.6. Zeta potential and loading efficiency for PLGA-GalN NPs were -0.456, 71%. The NPs indicated an amorphous status according to XRPD patterns and DSC thermograms. The PLGA-PEG-GalN NPs showed higher fungistatic activity than PLGA NPs. Conclusion: the results demonstrated that the antifungal activity of PLGA-PEG-GalN NPs was higher than pure amphotericin B and PLGA NPs.

Antimicrobial laser-activated sealants for combating surgical site infections.

Surgical-site infections (SSIs) occur in 2-5% of patients undergoing surgery in the US alone, impacting 300 000-500 000 lives each year, and presenting up to 11 times greater risk of death compared to patients without SSIs. The most common cause of SSI is Staphylococcus aureus, and methicillin-resistant S. aureus (MRSA) is the most common pathogen in community hospitals. Current clinical devices used for approximating incisions and traumatic lacerations include sutures, adhesives, tapes, or staples with or without antimicrobial incorporation. However, current closure technologies may not provide adequate protection against infection, are susceptible to wound dehiscence, and can result in delayed biomechanical recoveries. Laser-activated tissue repair is a sutureless technique in which chromophore-loaded sealants convert laser light energy to heat in order to induce rapid tissue sealing. Here, we describe the generation and evaluation of laser-activated sealant (LASE) biomaterials, in which, indocyanine green (ICG), an FDA-approved dye, was embedded in a silk fibroin matrix and cast into films as wound sealants. Silk-ICG films were subjected to different near-infrared (NIR) laser powers to identify temperatures optimal for laser sealing of soft tissues. A mathematical model was developed in order to determine the photothermal conversion efficiency of LASEs following laser irradiation. NIR laser activation of silk-ICG LASEs increased the recovery of skin biomechanical strength compared to sutured skin in full-thickness incisional wounds in immunocompetent mice, and live animal imaging indicated persistence of silk-ICG LASEs over several days. LASEs loaded with the antibiotic vancomycin demonstrated higher efficacies for combating MRSA infections in a mouse model of surgical site infection compared to antibacterial sutures. Our results demonstrate that LASEs can be loaded with antimicrobial drugs and may serve as new multifunctional biomaterials for rapid tissue sealing, repair and surgical site protection following surgery.

Biological and Catalytic Activities of Green Synthesized Silver Nanoparticles from the Leaf Infusion of Dracocephalum kotschyi Boiss.

The discovery and development of active compounds to eliminate drug resistance and side effects is a crucial process. In this study, the leaf infusion of Dracocephalum kotschyi Boiss as a novel green alternative is used to synthesize silver nanoparticles (Drac-AgNPs). Antibacterial, cytotoxicity effects, hemocompatibility, and the catalytic properties of these nanoparticles are evaluated. The synthesis of Drac-AgNPs is confirmed by UV-vis spectroscopy, X-ray diffraction, Fourier-transform infrared spectroscopy, and transmission electron microscopy, where Drac-AgNPs are spherical, with a size range of 5-63 nm. Their IC50 values against H1299 and MCF-7 cell lines are above 50 and 100 µg mL-1, respectively. Drac-AgNPs are effective against an inclusive range of the gram-positive and gram-negative bacteria, that is, Staphylococcus epidermidis, Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Serratia marcescens, and Pseudomonas aeruginosa, and a low hemolytic effect makes them an exceptional AgNP with a great hemocompatibility. They show a moderate catalytic-effect in terms of removing methylene blue, with 67% degradation. Altogether, Drac-AgNP, as a multi-tasker material, shows potential for the prevention and treatment of infections and photothermal/chemotherapy of cancers.

Molecular Insights into the Loading and Dynamics of Doxorubicin on PEGylated Graphene Oxide Nanocarriers.

Molecular dynamics (MD) simulations were performed to investigate the loading and dynamics of doxorubicin (DOX) anticancer drug on graphene oxide (GO) and poly(ethylene glycol) (PEG) decorated GO (PEGGO) nanocarriers in an aqueous environment at human body temperature (310 K) and physiological pH level of 7.4. Mechanisms of DOX adsorption on PEGGO as a function of PEG chain length were revealed. While the total DOX-nanocarrier interaction energy was the same for the DOX/GO (control), DOX/Sh-PEGGO (short PEG chains consisting of 15 repeat units), and DOX/L-PEGGO (long PEG chains consisting of 30 repeat units) within the margin of error, the PEG-DOX interactions increased with an increase in the PEG chain length. At the same time, the PEG-DOX solvent-accessible contact area almost doubled going from the short to long PEG chains. PEGylation of the GO effectively causes an increase in the average water density around the nanocarrier, which can act as a barrier, leading to the DOX migration to the solvated PEG-free part of the GO surface. This effect is more pronounced for shorter PEG chains. The DOX-DOX solvent-accessible contact area is smaller in the DOX/GO system, which means the drug molecules are less aggregated in this system. However, the level of DOX aggregation is slightly higher for the PEGGO systems. The computational results in this work shed light on the fact that increasing the PEG chain length benefits DOX loading on the nanocarrier, revealing an observation that is difficult to acertain through experiments. Moreover, a detailed picture is provided for the DOX adsorption and retention in PEGGO drug delivery systems, which would enable the researchers to improve the drug's circulation time, as well as its delivery and targeting efficiency.

A new strategy for the green synthesis of chondroitin sulfate-reduced gold nanoparticles; in vitro evaluation of synthesized nanoparticles.

Introduction: The application of gold nanoparticles (GNPs) in medicine is expanding as an effective therapeutic and diagnostic compound. Different polysaccharides with high biocompatibility and hydrophilic properties have been used for synthesis and capping of GNPs. Chondroitin sulfate (CHS) as a polysaccharide possesses a wide range of biological functions e.g. anti-oxidant, anti-inflammation, anti-coagulation, anti-atherosclerosis, anti-thrombosis with insignificant immunogenicity and has not been used for the green synthesis of GNPs. Methods: GNPs were synthesized using CHS, and their physicochemical properties were evaluated. The antibacterial activity of CHS-GNPs was estimated against both gram-positive and gram-negative bacteria. The cytotoxicity of CHS and CHS-GNPs was obtained by MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide) test, and the electrocatalytic activity of CHS-GNPs was investigated. The blood compatibility was evaluated by the in vitro hemolysis assay. Results: The absorption band at 527 nm reveals the reduction of Au3+ into GNPs. The transmission electron microscopy (TEM) image displays the spherical shape of GNPs in the range of 5.8-31.4 nm. The CHS and CHS-GNPs at 300 µg/mL revealed a maximum DPPH (1, 1-diphenyl-2-picrylhydrazyl) scavenging activity of 73% and 65%, respectively. CHS-GNPs showed antibacterial activity against Bacillus subtilis , while CHS has no antibacterial activity. CHS-GNPs exhibited a cytotoxicity effect against MDA-MB-468 and ßTC3 cancer cell lines, and the electrochemical study indicated a significant increase in electrocatalytic properties of CHS-GNPs coated electrode compared by the bare electrode. The hemolysis test proved the blood compatibility of CHS-GNPs. Conclusion: The results indicate the advantages of using CHS to produce blood-compatible GNPs with antioxidant, cytotoxic, and electrochemical properties.

Electrochemical analysis of anionic analytes in weakly supported media using electron transfer promotion effect: a case study on nitrite.

In this study, a simple technique was developed for the electrochemical detection of anionic analytes in weakly supported media. This was conducted by the use of electrochemical paper-based analytical devices (ePADs). A sensing platform was modified with nereistoxin and used to determine nitrite as a case study. The electrochemical response was improved due to the accelerated electron transfer between the sensing platform and the nitrite through the electrostatic interaction of the amino group of nereistoxin and the nitrite. The electrocatalytic current of the nitrite in the presence of nereistoxin was enhanced in the weakly supported media. By using nereistoxin as a signal enhancer, 97% of the electrochemical signal was obtained at the low ionic strength of the electrolyte, while less than 35% of this signal was obtained in the absence of nereistoxin. The limit of detection was as low as 20 nM using an ePAD. Generally, the proposed ePAD serves as a promising, efficient and low-cost device for sensing applications in weakly supported media.

Interactions of insulin with tragacanthic acid biopolymer: Experimental and computational study.

Alternative methods for insulin delivery instead of subcutaneous injection in diabetic patients is of great essential, and biocompatible polymers are one of the most efficient vehicles for this purpose. This research aims to investigate the capability of tragacanthic acid (TA) to bind insulin and release it under physiological conditions without alteration in the structure and conformation of insulin. Interactions between TA and insulin were studied using spectroscopic techniques and computational modeling by docking and molecular dynamics simulations. Our results demonstrate an entropy-driven spontaneous interaction between insulin and TA, where hydrogen bonds act as the main enthalpic contribution. According to our findings, the weak interaction between insulin and TA provides the basis for efficient capture and appropriate release of insulin by TA as a potential part of the insulin delivery system. In conclusion, tragacanth acid can be a proper candidate for insulin delivery.

Antidiabetic Potential of Prosopis farcta Roots: In Vitro Pancreatic Beta Cell Protection, Enhancement of Glucose Consumption, and Bioassay-Guided Fractionation.

By using the streptozotocin- (STZ-) induced cytotoxicity in ß-TC3 cells as an assay model, a bioassay-guided fractionation study was employed to isolate and characterize the potential antidiabetic principles of roots of Prosopis farcta. A combination of open column chromatography on reverse-phase silica gel using a water-ethanol gradient (10 : 90 to 100 : 0) followed by HPLC-based fractionation led to an active compound that appears to be composed of carbohydrate/sugar. When cell viability under STZ was reduced to 49.8 ± 4% (mean ± SD), treatment with the active compound at the concentration of 0.5 mg/mL either as a coadministration or a pretreatment improved the viability to 93 ± 1.9% and 91.5 ± 7%, respectively. The reduction in the mitochondrial membrane potential by STZ (47.34 ± 8.9% of control) was similarly recovered to 84.5 ± 4.3 (coadministration) and 88 ± 5.5% (pretreatment) by the active fraction. The bioassay-guided fractionation, ß-cell protective effect, and increased glucose consumption (up to 1.49-fold increase) in hepatocytes by the extracts and active fraction are also discussed.

All-Trans Retinoic Acid Grafted Poly Beta-Amino Ester Nanoparticles: A Novel Anti-angiogenic Drug Delivery System.

Purpose: Developing chemotherapy with nanoplatforms offers a promising strategy for effective cancer treatment. In the present study, we propose a novel all-trans retinoic acid (ATRA) grafted poly beta-amino ester (PBAE) copolymer for preparing nanoparticles (NPs). Methods: ATRA grafted PBAE (ATRA-g-PBAE) copolymer was synthesized by grafting ATRA to PBAE; it was characterized by proton nuclear magnetic resonance, Fourier transform infrared, and thermogravimetric analysis. ATRA-g-PBAE NPs were prepared by the solvent displacement method. Design-Expert software was employed to optimize size of NPs. The morphology was evaluated by transmission electron microscope, and ultraviolet-visible spectroscopy was applied for drug release. Cytotoxicity was evaluated toward HUVEC cell line, and the 3D collagencytodex model was used to evaluate anti-angiogenic property of PBAE, ATRA, and NPs. Results: The optimum size of the NPs was 139.4 ± 1.41 nm. After 21 days, 66.09% ± 1.39 and 42.14% ± 1.07 of ATRA were released from NPs at pH 5.8 and 7.4, respectively. Cell culture studies demonstrated antiangiogenic effects of ATRA-g-PBAE NPs. Anti-angiogenesis IC50 was 0.007 mg/mL for NPs (equal to 0.002 mg/mL of ATRA) and 0.005 mg/mL for free ATRA. Conclusion: This study proposes the ATRA-g-PBAE NPs with inherent anti-angiogenic effects as promising carrier for anticancer drugs with purpose of dual drug delivery.

One-step Synthesized Silver Nanoparticles Using Isoimperatorin: Evaluation of Photocatalytic, and Electrochemical Activities.

In the current study, isoimperatorin, a natural furanocoumarin, is used as a reducing reagent to synthesize isoimperatorin mediated silver nanoparticles (Iso-AgNPs), and photocatalytic and electrocatalytic activities of Iso-AgNPs are evaluated. Iso-AgNPs consisted of spherically shaped particles with a size range of 79-200 nm and showed catalytic activity for the degradation (in high yields) of New Fuchsine (NF), Methylene Blue (MB), Erythrosine B (ER) and 4-chlorophenol (4-CP) under sunlight irradiation. Based on obtained results, Iso-AgNPs exhibited 96.5%, 96.0%, 92%, and 95% degradation rates for MB, NF, ER, and 4-CP, respectively. The electrochemical performance showed that the as-prepared Iso-AgNPs exhibited excellent electrocatalytic activity toward hydrogen peroxide (H2O2) reduction. It is worth noticing that the Iso-AgNPs were used as electrode materials without any binder. The sensor-based on binder-free Iso-AgNPs showed linearity from 0.1 µM to 4 mM with a detection limit of 0.036 µM for H2O2. This binder-free and straightforward strategy for electrode preparation by silver nanoparticles may provide an alternative technique for the development of other nanomaterials based on isoimperatorin under green conditions. Altogether, the application of isoimpratorin in the synthesis of nano-metallic electro and photocatalysts, especially silver nanoparticles, is a simple, cost-effective and efficient approach.