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1.
Nanomaterials (Basel) ; 12(19)2022 Sep 29.
Article in English | MEDLINE | ID: mdl-36234554

ABSTRACT

Drug loading in electrospun nanofibers has gained a lot of attention as a novel method for direct drug release in an injury site to accelerate wound healing. The present study deals with the fabrication of silk fibroin (SF)-chitosan (CS)-silver (Ag)-curcumin (CUR) nanofibers using the electrospinning method, which facilitates the pH-responsive release of CUR, accelerates wound healing, and improves mechanical properties. Response surface methodology (RSM) was used to investigate the effect of the solution parameters on the nanofiber diameter and morphology. The nanofibers were characterized via Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), zeta potential, and Dynamic Light Scattering (DLS). CS concentration plays a crucial role in the physical and mechanical properties of the nanofibers. Drug loading and entrapment efficiencies improved from 13 to 44% and 43 to 82%, respectively, after the incorporation of Ag nanoparticles. The application of CS hydrogel enabled a pH-responsive release of CUR under acid conditions. The Minimum Inhibitory Concentration (MIC) assay on E. coli and S. aureus bacteria showed that nanofibers with lower CS concentration cause stronger inhibitory effects on bacterial growth. The nanofibers do not have any toxic effect on cell culture, as revealed by in vitro wound healing test on NIH 3T3 fibroblasts.

2.
Biophys Rev ; 14(2): 517-543, 2022 Apr.
Article in English | MEDLINE | ID: mdl-35528034

ABSTRACT

Cancer has long been a leading cause of death. The primary tumor, however, is not the main cause of death in more than 90% of cases. It is the complex process of metastasis that makes cancer deadly. The invasion metastasis cascade is the multi-step biological process of cancer cell dissemination to distant organ sites and adaptation to the new microenvironment site. Unraveling the metastasis process can provide great insight into cancer death prevention or even treatment. Microfluidics is a promising platform, that provides a wide range of applications in metastasis-related investigations. Cell culture microfluidic technologies for in vitro modeling of cancer tissues with fluid flow and the presence of mechanical factors have led to the organ-on-a-chip platforms. Moreover, microfluidic systems have also been exploited for capturing and characterization of circulating tumor cells (CTCs) that provide crucial information on the metastatic behavior of a tumor. We present a comprehensive review of the recent developments in the application of microfluidics-based systems for analysis and understanding of the metastasis cascade from a wider perspective.

3.
Int J Pharm ; 618: 121647, 2022 Apr 25.
Article in English | MEDLINE | ID: mdl-35288221

ABSTRACT

In this study, the potential of using MIL-100(Fe) metal-organic framework (MOF) for loading and controlling the release of dacarbazine (DTIC) was evaluated for in vitro treatment of melanoma. The drug loading was performed during the green synthesis of MIL-100(Fe) in an aqueous media without using any harmful solvents, to obtain MIL-DTIC. The surface of this structure was then coated with polyethylene glycol (PEG) in the same aqueous solution to synthesize MIL-DTIC-PEG. The synthesized samples were characterized using various methods. Their release profile was studied in phosphate-buffered saline (PBS) and simulated cutaneous medium (SCM). The cytotoxicity of DTIC and its nano-MOF formulation were investigated against melanoma A375 cell lines. The results revealed that the PEG coating (PEGylation) changed the surface charge of MOF from -2.8 ± 0.9 mV to -42.8 ± 1.2 mV, which can contribute to the colloidal stability of MOF. The PEGylation showed a significant effect on controlled drug release, especially in SCM, which increases the complete release time from 60 h to 12 days. Moreover, both of the drug-containing MOFs showed more toxicity than DTIC and unloaded MOFs, confirming that the cumulative release of drug and better cellular uptake of NPs lead to increased toxicity.


Subject(s)
Melanoma , Metal-Organic Frameworks , Humans , Dacarbazine/pharmacology , Delayed-Action Preparations/therapeutic use , Melanoma/drug therapy , Metal-Organic Frameworks/chemistry , Polyethylene Glycols/therapeutic use
4.
Anal Chim Acta ; 1186: 339115, 2021 Nov 22.
Article in English | MEDLINE | ID: mdl-34756251

ABSTRACT

Isolation and characterization of circulating tumor cells (CTCs) found in blood samples of cancer patients have been considered as a reliable source for cancer prognosis and diagnosis. A new continuous microfluidic platform has been designed in this investigation for simultaneous capture and characterization of CTCs based on their deformability. The deformability-based chip (D-Chip) consists of two sections of separation and characterization where slanted weirs with a gap of 7 µm were considered. Although sometimes CTCs and leukocytes have the same size, the deformability differs in such a way that can be exploited for enrichment purposes. MCF7 and MDA-MB-231 cell lines were used for the initial evaluation of the D-Chip performance. In the separation section, cancer cells were isolated based on deformability differences with an efficiency of higher than 93% (∼average capturing capacity of 2085 out of 2200 cancer cells ml-1) and with significantly high purity (15-40 WBCs ml-1; ∼5 log depletion of WBCs). Cancer cells were categorized based on the deformability difference in the characterization section. Subsequently, 15 clinical blood samples from breast cancer patients were analyzed by the D-Chip. Suggest 'The chip detected CTCs in all patient samples, processed the blood sample at a high throughput of 5.3 ml/h, and properly categorized CTCs based on deformability differences. Further characterization showed that the highly deformable breast cancer CTCs in our patient samples also showed higher potential of metastasis in support of a broader correlation between deformability of CTCs and metastatic behavior.


Subject(s)
Microfluidic Analytical Techniques , Neoplastic Cells, Circulating , Cell Line, Tumor , Cell Separation , Humans , Microfluidics
5.
ACS Omega ; 6(16): 10816-10827, 2021 Apr 27.
Article in English | MEDLINE | ID: mdl-34056236

ABSTRACT

Chitosan/poly(vinyl alcohol)/amino-functionalized montmorillonite nanocomposite electrospun membranes with enhanced adsorption capacity and thermomechanical properties were fabricated and utilized for the removal of a model cationic dye (Basic Blue 41). Effects of nanofiller concentrations (up to 3.0 wt %) on the morphology and size of the nanofibers as well as the porosity and thermomechanical properties of the nanocomposite membranes are studied. It is shown that the incorporation of the nanoclay particles with ∼10 nm lateral sizes into the polymer increases the size of the pores by about 80%. To demonstrate the efficiency of the adsorbents, the dye removal rate is investigated as a function of pH, adsorbent dosage, dye concentration, and nanofiller loading. The highest and fastest dye removal occurs for the nanofibrous membranes containing 2 wt % nanofiller, where about 80% of the cationic dye is removed after 15 min. This performance is at least 20% better than the pristine chitosan/poly(vinyl alcohol) membrane. The thermal stability and compression resistance of the nanocomposite membranes are found to be higher than those of the pristine membrane. In addition, reusability studies show that the dye removal performance of this nanocomposite membrane reduces by only about 5% over four cycles. The adsorption kinetics is explained by the Langmuir isotherm model and is expressed by a pseudo-second-order kinetic mechanism that determines a spontaneous chemisorption process. The results of this study provide a valuable perspective on the fabrication of high-performance, reusable, and efficient electrospun fibrous nanocomposite adsorbents.

6.
Carbohydr Polym ; 254: 117465, 2021 Feb 15.
Article in English | MEDLINE | ID: mdl-33357924

ABSTRACT

Designing multifunctional surfaces is key to develop advanced materials for orthopedic applications. In this study, we design a double-layer coating, assembled onto the completely regular titania nanotubes (cRTNT) array. Benefiting from the biological and topological characteristics of chitosan nanofibers (CH) and reduced graphene oxide (RGO) through a unique assembly, the designed material features promoted osteoblast cell viability, prolonged antibiotic release profile, as well as inhibited bacterial biofilm formation. The synergistic effect of RGO and CH on the biological performance of the surface is investigatSed. The unique morphology of the nanofibers leads to the partial coverage of RGO-modified nanotubes, providing an opportunity to access the sublayer properties. Another merit of this coating lies in its morphological similarity to the extracellular matrix (ECM) to boost cellular performance. According to the results of this study, this platform holds promising advantages over the bare and bulk biopolymer-modified TNTs.


Subject(s)
Chitosan/chemical synthesis , Coated Materials, Biocompatible/chemistry , Graphite/chemistry , Nanocomposites/chemistry , Osteoblasts/drug effects , Titanium/chemistry , Anti-Bacterial Agents/pharmacology , Biofilms/drug effects , Biofilms/growth & development , Cell Adhesion/drug effects , Cell Line , Cell Survival/drug effects , Coated Materials, Biocompatible/pharmacology , Drug Carriers , Drug Liberation , Humans , Kinetics , Nanocomposites/ultrastructure , Nanotubes/chemistry , Nanotubes/ultrastructure , Osteoblasts/cytology , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Vancomycin/pharmacology
7.
Int J Pharm ; 592: 120068, 2021 Jan 05.
Article in English | MEDLINE | ID: mdl-33188894

ABSTRACT

In this study, physically cross-linked hydrogels were developed by freezing-thawing method while different concentrations of honey were included into the hydrogels for accelerated wound healing. The hydrogel was composed of chitosan, polyvinyl alcohol (PVA), and gelatin with the ratio of 2:1:1 (v/v), respectively. Further, the effect of honey concentrations on antibacterial properties, and cell behavior was investigated. In vivo studies, including wound healing mechanism using rat model and histological analysis of section tissue samples were performed. The results illustrated that the incorporation of honey in hydrogels increased the ultimate strain of hydrogels approximately two times, while reduced the ultimate tensile strength and elastic modulus of hydrogels. Moreover, the antibacterial activities of samples were increased by increasing the concentration of honey. Regarding MTT assay, as the concentration of honey increased, the cell viability of hydrogels was enhanced until an optimal amount of honey. Further, the integration of honey into the hydrogel matrix results in the maintenance of a well-structured layer of epidermis containing mature collagen and accelerates the rate of wound healing. The 3D Chitosan/PVA/Gelatin hydrogel containing honey with appropriate mechanical, antibacterial activity, and biocompatibility could be a promising approach for wound healing.


Subject(s)
Chitosan , Honey , Animals , Gelatin , Hydrogels , Polyvinyl Alcohol , Rats , Wound Healing
8.
Carbohydr Polym ; 245: 116465, 2020 Oct 01.
Article in English | MEDLINE | ID: mdl-32718603

ABSTRACT

In the article, a bilayer nanocomposite scaffold made of oxidized alginate (OAL), gelatin (G), and silk fibroin (SF) has been prepared via combining electrospinning, in situ gas foaming, in situ crosslinking and freeze drying methods. The physicochemical and mechanical properties, as well as thermal stability of the proposed composite, have been investigated by SEM, FTIR, XRD, tensile, and TGA analysis. The data indicate that structure and degree of crosslinking play a vital role in adjusting the physical and mechanical properties of composite scaffolds. Further, the authors find a favorable adipose-derived mesenchymal stem cell's (AMSC) attachment and distribution within this novel hydrogel-electrospun composite. Such a nanocomposite structure with its promising properties and cell-material interaction may be considered as a new scaffold for different tissue engineering applications.


Subject(s)
Alginates/chemistry , Fibroins/chemistry , Gelatin/chemistry , Hydrogels/chemistry , Nanocomposites/chemistry , Tissue Engineering/methods , Tissue Scaffolds/chemistry , Animals , Cell Proliferation , Cell Survival , Cross-Linking Reagents/chemistry , Mesenchymal Stem Cells/physiology , Nanofibers/chemistry , Oxidation-Reduction , Porosity , Swine , Temperature
9.
Environ Res ; 188: 109555, 2020 09.
Article in English | MEDLINE | ID: mdl-32559687

ABSTRACT

In the last decades, numerous attempts have been made to prevent microbial pollution spreading, using antibacterial agents. Zeolitic imidazolate framework-8 (ZIF-8) belongs to a subgroup of metal organic frameworks (MOFs) merits of attention due to the zinc ion clusters and its effective antibacterial activity. In this work, Ag-doped magnetic microporous γ-Fe2O3@SiO2@ZIF-8-Ag (FSZ-Ag) was successfully synthesized by a facile methodology in room temperature and used as an antibacterial agent against the growth of the Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus bacteria. Several characterization methods were applied to analyze the properties of the materials, and the results confirmed the accuracy of the synthesis procedure. Silver ions have employed to enhance the efficiency of antibacterial activity. As the results illustrated, FSZ-Ag nanostructured material had superior performance to inactive E. coli and S. aureus in growth inhibition test in liquid media. The best antibacterial activity as minimum inhibitory concentration (MIC) was 100 mg/L of FSZ-Ag against both bacteria. Leaching rates of silver ions showed that 80% of Ag released in the solutions, which was responsible for inhibiting the growth of bacteria. Also, fluorescence microscopy was used to investigate bacterial viability after 20 h contacting FSZ-Ag to distinguish live and dead bacteria by staining with DAPI and PI fluorescence stains. This novel magnetic nanostructured material is an excellent promising candidate to use in biological applications as high potential bactericidal materials.


Subject(s)
Metal Nanoparticles , Metal-Organic Frameworks , Nanostructures , Anti-Bacterial Agents/pharmacology , Escherichia coli , Magnetic Phenomena , Microbial Sensitivity Tests , Silicon Dioxide , Silver/pharmacology , Staphylococcus aureus
10.
J Biotechnol ; 309: 131-141, 2020 Feb 10.
Article in English | MEDLINE | ID: mdl-31935418

ABSTRACT

Chondroitinase ABC I (cABC I) has received notable attention in treatment of spinal cord injuries and its application as therapeutics has been limited due to low thermal stability at physiological temperature. In this study, cABC I enzyme was immobilized on the dextran-coated Fe3O4 nanoparticles through physical adsorption to improve the thermal stability. The nanoparticles were characterized using XRD, SEM, VSM, and FTIR analyses. Response surface methodology and central composite design were employed to assess factors affecting the activity of immobilized cABC I. Experimental results showed that pH 6.3, temperature 24 °C, enzyme/support mass ratio 1.27, and incubation time 5.7 h were the optimal immobilization conditions. It was found that thermal stability of immobilized cABC I was significantly improved. In-vitro cABC I release was studied under pH 7.5 and temperature 37 °C and the results indicated that 70 % release occurred after 9 h and the release mechanism was first-order kinetic model.


Subject(s)
Chondroitin ABC Lyase/chemistry , Chondroitin ABC Lyase/metabolism , Dextrans/chemistry , Enzymes, Immobilized/chemistry , Magnetite Nanoparticles/chemistry , Adsorption , Chondroitin ABC Lyase/genetics , Enzyme Stability , Escherichia coli/genetics , Escherichia coli/metabolism , Hydrogen-Ion Concentration , Kinetics , Proteus vulgaris/genetics , Temperature , X-Ray Diffraction
11.
Front Bioeng Biotechnol ; 8: 582713, 2020.
Article in English | MEDLINE | ID: mdl-33520951

ABSTRACT

Carbon nanotubes (CNTs) coatings have been shown over the past few years as a promising material for neural interface applications. In particular, in the field of nerve implants, CNTs have fundamental advantages due to their unique mechanical and electrical properties. In this study, carbon nanotubes multi-electrode arrays (CNT-modified-Au MEAs) were fabricated based on gold multi-electrode arrays (Au-MEAs). The electrochemical impedance spectra of CNT-modified-Au MEA and Au-MEA were compared employing equivalent circuit models. In comparison with Au-MEA (17 Ω), CNT-modified-Au MEA (8 Ω) lowered the overall impedance of the electrode at 1 kHz by 50%. The results showed that CNT-modified-Au MEAs have good properties such as low impedance, high stability and durability, as well as scratch resistance, which makes them appropriate for long-term application in neural interfaces.

12.
Int J Nanomedicine ; 14: 8769-8786, 2019.
Article in English | MEDLINE | ID: mdl-31806971

ABSTRACT

INTRODUCTION: To date, numerous iron-based nanostructures have been designed for cancer therapy applications. Although some of them were promising for clinical applications, few efforts have been made to maximize the therapeutic index of these carriers. Herein, PEGylated silica-coated iron oxide nanoparticles (PS-IONs) were introduced as multipurpose stimuli-responsive co-delivery nanocarriers for a combination of dual-drug chemotherapy and photothermal therapy. METHODS: Superparamagnetic iron oxide nanoparticles were synthesized via the sonochemical method and coated by a thin layer of silica. The nanostructures were then further modified with a layer of di-carboxylate polyethylene glycol (6 kDa) and carboxylate-methoxy polyethylene glycol (6 kDa) to improve their stability, biocompatibility, and drug loading capability. Doxorubicin (DOX) and cisplatin (CDDP) were loaded on the PS-IONs through the interactions between the drug molecules and polyethylene glycol. RESULTS: The PS-IONs demonstrated excellent cellular uptake, cytocompatibility, and hemocompatibility at the practical dosage. Furthermore, in addition to being an appropriate MRI agent, PS-IONs demonstrated superb photothermal property in 0.5 W/cm2 of 808 nm laser irradiation. The release of both drugs was effectively triggered by pH and NIR irradiation. As a result of the intracellular combination chemotherapy and 10 min of safe power laser irradiation, the highest cytotoxicity for iron-based nanocarriers (97.3±0.8%) was achieved. CONCLUSION: The results of this study indicate the great potential of PS-IONs as a multifunctional targeted co-delivery system for cancer theranostic application and the advantage of employing proper combination therapy for cancer eradication.


Subject(s)
Antineoplastic Agents/administration & dosage , Cisplatin/administration & dosage , Doxorubicin/administration & dosage , Magnetite Nanoparticles/administration & dosage , Phototherapy/methods , Animals , Antineoplastic Agents/pharmacokinetics , Breast Neoplasms/drug therapy , Cisplatin/pharmacokinetics , Combined Modality Therapy , Contrast Media/administration & dosage , Contrast Media/pharmacokinetics , Doxorubicin/pharmacokinetics , Drug Delivery Systems/methods , Drug Liberation , Humans , Hydrogen-Ion Concentration , Hyperthermia, Induced/methods , Lasers , MCF-7 Cells , Magnetic Resonance Imaging/methods , Magnetite Nanoparticles/chemistry , Mice , Polyethylene Glycols/chemistry
13.
Mater Sci Eng C Mater Biol Appl ; 103: 109688, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31349405

ABSTRACT

In order to regenerate bone defects, bioactive hierarchically scaffolds play a key role due to their multilevel porous structure, high surface area, enhanced nutrient transport and diffusion. In this study, novel hierarchically porous silk fibroin (SF) and silk fibroin-bioactive glass (SF-BG) composite were fabricated with controlled architecture and interconnected structure, by combining indirect three-dimensional (3D) inkjet printing and freeze-drying methods. Further, the effect of 45S5 Bioactive glass particles of different sizes (<100 nm and 6 µm) on mechanical strength and cell behavior was investigated. The results demonstrated that the hierarchical structure in this scaffold was composed of two levels of pores in the order of 500-600 µm and 10-50 µm. The prepared SF-BG composite scaffolds utilized by nano and micro particles possessed mechanical properties with a compressive strength of 0.94 and 1.2 MPa, respectively, in dry conditions. In a wet condition, the hierarchically porous scaffolds did not exhibit any fluctuation after compression load cell and were incredibly flexible, with excellent mechanical stability. The SF-BG composite scaffold with nanoparticles presented a significant 50% increase in attachment of human bone marrow stem cells in comparison with SF and SF-BG scaffold with microparticles. Moreover, SF-BG scaffolds promoted alkaline phosphatase activity as compared to SF scaffolds without BG particles on day 14. In brief, the 3D porous silk fibroin-based composites containing BG nanoparticles with excellent mechanical properties are promising scaffolds for bone tissue regeneration in high load-bearing applications.


Subject(s)
Bone Marrow Cells/metabolism , Fibroins/chemistry , Glass/chemistry , Nanoparticles/chemistry , Printing, Three-Dimensional , Stem Cells/metabolism , Tissue Scaffolds/chemistry , Bone Marrow Cells/cytology , Compressive Strength , Humans , Particle Size , Porosity , Stem Cells/cytology
14.
Artif Cells Nanomed Biotechnol ; 47(1): 2721-2728, 2019 Dec.
Article in English | MEDLINE | ID: mdl-31272239

ABSTRACT

Chondroitinase ABCI (cABCI) is a drug enzyme that can be used to treat spinal cord injuries. Due to low thermal stability of cABCI, this enzyme was immobilized on Fe3O4 nanoparticle to increase its thermal stability. The size and morphology, structure and magnetic property of the Fe3O4 nanoparticles were characterized by the analyses of SEM, XRD and VSM, respectively, and FTIR spectroscopy was employed to confirm the immobilization of cABCI on the surface of Fe3O4 nanoparticles. The results indicated that the optimum conditions for pH, temperature, cABCI-to-Fe3O4 mass ratio and incubation time in immobilization process were 6.5, 15 °C, 0.75 and 4.5 h, respectively, and about 0.037 mg cABCI was bound to 1 mg of Fe3O4 nanoparticles at these conditions. The value of Vmax was the same for free and immobilized cABCI, but Km value for immobilized cABCI was 1.6 times higher than that for free one. The storage stability of immobilized cABCI was significantly enhanced at low temperatures, e.g. free cABCI retained 19% of its activity after six days at -20 °C, while the immobilized one retained 96% of its activity. In vitro release of cABCI from Fe3O4 particles showed that about 94% of the enzyme was released after 6 h.


Subject(s)
Chondroitinases and Chondroitin Lyases/chemistry , Chondroitinases and Chondroitin Lyases/metabolism , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Magnetite Nanoparticles/chemistry , Enzyme Stability , Hydrogen-Ion Concentration , Kinetics , Temperature
15.
Chemosphere ; 229: 188-199, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31078033

ABSTRACT

Nanotechnology is gaining more attention in biotechnological applications as a research area with a huge potential. Nanoparticles (NPs) can influence the rate of anaerobic digestion (AD) as the nano-sized structures, with specific physicochemical properties, interact with substrate and microorganisms. The present work has classified the various types of additives used to improve the AD processes. Nanomaterials as new additives in AD process are classified into four categories: Zero-valent metallic NPs, Metal oxide NPs, Carbon based nanomaterials, and Multi-compound NPs. In the following, application of nanomaterials in AD process is reviewed and negative and positive effects of these materials on the AD process and subsequently biogas production rate are discussed. This study confirms that design and development of new nano-sized compounds can improve the performances of the AD processes.


Subject(s)
Nanostructures , Nanotechnology/methods , Anaerobiosis , Biofuels/microbiology , Nanostructures/chemistry
16.
Int J Pharm ; 564: 350-358, 2019 Jun 10.
Article in English | MEDLINE | ID: mdl-31028800

ABSTRACT

In the current study, two series of antimicrobial dressings conjugated with silver sulfadiazine (SSD) and silver nanoparticles (AgNPs) were developed and evaluated for chronic wound healing. Highly porous polycaprolactone (PCL)/polyvinyl alcohol (PVA) nanofibers were loaded with different concentrations of SSD or AgNPs and compared comprehensively in vitro and in vivo. SSD and AgNPs indicated a strong and equal antimicrobial activity against S. aureus. However, SSD had more toxicity against fibroblast cells over one week in vitro culture. An in vivo model of wound healing on male Wistar rats was developed with a full thickness wound. All the wound dressings indicated enough flexibility and hydrophilicity, which resulted an adequate adhesion into the wound closure. After 30 days, the control group without any treatment indicated 31% wound closure while the group treated with PCL/PVA (without antimicrobial components) indicated 44% wound closure. Presence of antimicrobial components in the PCL/PVA nanofibers resulted into a lower inflammation response leading to a faster proliferation and maturation phases. In agreement with the higher biocompatibility of AgNPs than SSD, a faster angiogenesis, epithelialization and subsequently, remodeling were observed for the wound dressings loaded with AgNPs. The group treated with the highest concentration of AgNPs showed the fastest healing process leading to a final epithelialization with 96% wound closure after 30 days. This study indicated that AgNPs have higher biocompatibility and regulate wound healing process more efficiently compared to SSD. PCL/PVA nanofibers conjugated with AgNPs are promising wound dressings for full-thickness wounds.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Bandages , Metal Nanoparticles/administration & dosage , Silver Sulfadiazine/administration & dosage , Silver/administration & dosage , Wound Healing/drug effects , Animals , Cell Survival/drug effects , Cells, Cultured , Fibroblasts/drug effects , Humans , Male , Rats, Wistar , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development
17.
Sci Rep ; 9(1): 2985, 2019 02 27.
Article in English | MEDLINE | ID: mdl-30814648

ABSTRACT

Multi electrode arrays (MEA) have been exploited in different electrophysiological applications. In neurological applications, MEAs are the vital interfaces between neurons and the electronic circuits with dual role; transmitting electric signal to the neurons and converting neural activity to the electric signal. Since the performance of the electrodes has a direct effect on the quality of the recorded neuronal signal, as well as the stimulation, the true choice of electrode material for MEA is crucial. Gold is one of the best candidates for fabrication of MEAs due to its high electrical conductivity, biocompatibility and good chemical stability. However, noble metals such as gold do not adhere well to the glass substrate. Consequently while exposing to the water, gold films are damaged, which impose limitations in the exploiting of gold thin films as the electrode. In this paper, a simple and cost effective method for the fabrication of gold electrode arrays is proposed. Using various mechanical (adhesion test and scratch strength), morphological (AFM and SEM) and electrochemical methods, the fabricated electrodes are characterized. The results show that the fabricated electrode arrays have significantly high scratch strength and stability within the aqueous medium. In addition, the electrical properties of the electrodes have been improved. The proposed electrodes have the potential to be exploited in other applications including electronics, electrochemistry, and biosensors.

18.
Appl Microbiol Biotechnol ; 103(8): 3393-3406, 2019 Apr.
Article in English | MEDLINE | ID: mdl-30868206

ABSTRACT

Production of insulin-like growth factor 1 (IGF1) in Escherichia coli mostly results in the formation of inclusion bodies. In the present study, IGF1 was fused to disulfide bond oxidoreductase A (DsbA) and expressed in SHuffle™ T7 strain, in order to obtain correctly folded protein. Soluble expression and IMAC purification of DsbA-IGF1 were optimized by applying the Box-Behnken design of response surface methodology. The optimization greatly increased concentration of soluble protein from 317 to 2600 mg/L, and IMAC yield from 400 to 1900 mg/L. Results of ANOVA showed induction OD600 and temperature had significant effects on the soluble protein expression while isopropyl-ß-d thiogalactoside, in the concentrations tested, displayed no significant effect. Moreover, the three parameters of the binding buffer including, pH, concentration of NaCl, and imidazole displayed significant effects on the IMAC yield. Then, purified DsbA-IGF1 was cleaved by human rhinovirus 3C protease, and authentic IGF1 was obtained in flow through of a subtractive IMAC. Final polishing of the protein by reversed-phase HPLC yielded IGF1 with purity of 96%. The quality attributes of purified IGF1 such as purity, identity, molecular size, molecular weight, secondary structure, and biological activity were assessed and showed to be comparable to the standard IGF1. The final yield of purified IGF1 was estimated to be 120 ± 18 mg from 1 L of the culture. Our results demonstrated a simple and easily scalable strategy for production of large amounts of bioactive IGF1 by rational designing soluble protein expression, and further optimization of expression and purification methods.


Subject(s)
Escherichia coli K12/genetics , Escherichia coli Proteins/genetics , Industrial Microbiology/methods , Insulin-Like Growth Factor I/genetics , Insulin-Like Growth Factor I/isolation & purification , Protein Disulfide-Isomerases/genetics , 3C Viral Proteases , Analysis of Variance , Animals , Cell Proliferation/drug effects , Chromatography, Affinity , Chromatography, High Pressure Liquid , Cysteine Endopeptidases/metabolism , Escherichia coli K12/metabolism , Escherichia coli Proteins/metabolism , Gene Expression , Humans , Insulin-Like Growth Factor I/chemistry , Insulin-Like Growth Factor I/metabolism , Mice , Models, Theoretical , Molecular Weight , NIH 3T3 Cells , Protein Disulfide-Isomerases/metabolism , Protein Structure, Secondary , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Viral Proteins/metabolism
19.
J Cell Physiol ; 234(8): 13617-13628, 2019 08.
Article in English | MEDLINE | ID: mdl-30613971

ABSTRACT

While the differentiation factors have been widely used to differentiate mesenchymal stem cells (MSCs) into various cell types, they can cause harm at the same time. Therefore, it is beneficial to propose methods to differentiate MSCs without factors. Herein, magnetoelectric (ME) nanofibers were synthesized as the scaffold for the growth of MSCs and their differentiation into neural cells without factors. This nanocomposite takes the advantage of the synergies of the magnetostrictive filler, CoFe2 O 4 nanoparticles (CFO), and piezoelectric polymer, polyvinylidene difluoride (PVDF). Graphene oxide nanosheets were decorated with CFO nanoparticles for a proper dispersion in the polymer through a hydrothermal process. After that, the piezoelectric PVDF polymer, which contained the magnetic nanoparticles, underwent the electrospun process to form ME nanofibers, the ME property of which has the potential to be used in areas such as tissue engineering, biosensors, and actuators.


Subject(s)
Cell Differentiation , Mesenchymal Stem Cells/cytology , Nanocomposites , Tissue Engineering/methods , Tissue Scaffolds/chemistry , Animals , Biocompatible Materials/chemistry , Cobalt , Ferric Compounds , Graphite , Humans , Magnetics , Metal Nanoparticles/chemistry , Metal Nanoparticles/ultrastructure , Mice , Nanocomposites/chemistry , Nanocomposites/ultrastructure , Nanofibers/chemistry , Nanofibers/ultrastructure , Polyvinyls
20.
J Environ Manage ; 233: 660-672, 2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30611099

ABSTRACT

Herein, Kiwi peel activated carbon (AC), Materials Institute Lavoisier (MIL-88B (Fe), and AC/MIL-88B (Fe) composite were synthesized and used as catalysts to degrade Reactive Red 198. The material properties were analyzed by the FTIR, BET-BJH, XRD, FESEM, EDX, TGA, and UV-Vis/DRS. The BET surface area of AC, MIL-88B (Fe) and AC/MIL-88B (Fe) was 1113.3, 150.7, and 199.4 m2/g, respectively. The band gap values (Eg) estimated by Tauc plot method, were obtained 5.06, 4.19 and 3.79 eV for AC, MIL-88B (Fe) and AC/MIL-88B (Fe), respectively. The results indicated that the AC/MIL-88B (Fe) composite had higher photocatalytic activity (99%) than that of pure AC (79%) and MIL-88B (Fe) catalysts (87%). The decolorization kinetic was matched well with the second-order model. Moreover, the data were modeled using least squares support vector machine which optimized with Cuckoo optimization algorithm. The optimal parameters were found 0.837 and 3.49e+02 based on σ2 and γ values, respectively. The mean square error (MSE) and correlation coefficient (R2) values were obtained 3.97 and 0.948. Therefore, the attained data, materials characterization and prediction of modeling validate the composite form of MIL-88B(Fe) with new AC, had better photocatalytic activity in comparison with the individual form.


Subject(s)
Metal-Organic Frameworks , Nanocomposites , Charcoal , Least-Squares Analysis , Support Vector Machine , Wastewater
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