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1.
Langmuir ; 40(28): 14486-14503, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38970496

RESUMO

Electrochemical sensing is emerging as a method of choice for the sensing and monitoring of contaminants in water. Various sensing platforms have been designed for sensing heavy metal ions and organic pollutants in water bodies. Herein, we report a new electrochemical platform that can be used for the detection of both heavy metal ions and nitro-based organic contaminants in water bodies. The electrochemical sensor uses a modified electrode based on Fe3S4-impregnated zirconium phosphate (ZrP) nanoparticles synthesized by a simple ultrasonication method. The ZrP@Fe3S4 nanoparticles were thoroughly characterized by power X-ray diffraction (PXRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDX), and ζ-potential studies. The material exhibits an excellent electrochemical performance for the detection of Pb2+, Hg2+, nitrophenol, nitroaniline, and picric acid with low limits of detection of ca. 0.93, 0.70, 0.98, 1.10, and 1.53 ppm, respectively. Since ZrP@Fe3S4 nanoparticles are magnetically recyclable, their adsorption capacity and recyclability have been thoroughly investigated for the uptake of Pb2+ and Hg2+ ions from contaminated water. We observed that the adsorption of Pb2+ and Hg2+ ions on ZrP@Fe3S4 is best described by the Langmuir isotherm and pseudo-second-order kinetic models, with adsorption capacities of 219.44 and 118.4 mg/g, respectively. Similarly, the removal efficiency of ZrP@Fe3S4 was found to be 91, 57.6, and 31.3% for nitrophenol, nitroaniline, and picric acid, respectively. Furthermore, the theoretical calculations using density functional theory (DFT) were carried out to find the adsorption energy, affinity, and point of adsorption, which are in line with the experimental results. DFT calculations further suggest that the incorporation of Fe3S4 on ZrP improves the surface charge density and promotes efficient electron transfer between the electrode and the analyte. We have shown the real-time analysis of Dal lake water as a proof of concept, and the synthesized composite exhibits good recovery and promising results for metal ion sensing. ZrP@Fe3S4 demonstrated an excellent cycling stability and long-term stability without noticeable degradation for 1 week.

2.
Tissue Eng Regen Med ; 21(5): 711-721, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38520636

RESUMO

BACKGROUND: In this study an approach was made to efficaciously synthesize gold enhanced titania nanorods by electrospinning. This study aims to address effects of gold enhanced titania nanorods on muscle precursor cells. Additionally, implant related microbial infections are prime cause of various disastrous diseases. So, there is predictable demand for synthesis of novel materials with multifunctional adaptability. METHODS: Herein, gold nanoparticles were attached on titania nanorods and described using many sophisticated procedures such as XRD, SEM, EDX and TEM. Antimicrobial studies were probed against Gram-negative Escherichia coli. C2C12 cell lines were exposed to various doses of as-prepared gold enhanced titania nanorods in order to test in vitro cytotoxicity and proliferation. Cell sustainability was assessed through Cell Counting Kit-8 assay at regular intervals. A phase-contrast microscope was used to examine morphology of exposed C2C12 cells and confocal laser scanning microscope was used to quantify cell viability. RESULTS: The findings indicate that titania nanorods enhanced with gold exhibit superior antimicrobial efficacy compared to pure titania. Furthermore, newly synthesized gold-enhanced titania nanorods illustrate that cell viability follows a time and concentration dependent pattern. CONCLUSION: Consequently, our study provides optimistic findings indicating that titania nanorods adorned with gold hold significant potential as foundational resource for developing forthcoming antimicrobial materials, suitable for applications both in medical and biomedical fields. This work also demonstrates that in addition to being extremely biocompatible, titania nanorods with gold embellishments may be used in a range of tissue engineering applications in very near future.


Assuntos
Proliferação de Células , Escherichia coli , Ouro , Nanotubos , Titânio , Ouro/química , Ouro/farmacologia , Titânio/farmacologia , Titânio/química , Animais , Proliferação de Células/efeitos dos fármacos , Camundongos , Escherichia coli/efeitos dos fármacos , Nanotubos/química , Linhagem Celular , Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Sobrevivência Celular/efeitos dos fármacos
3.
Biomater Adv ; 158: 213773, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38277903

RESUMO

Despite being an approved antiemetic for more than five decades, the clinical usefulness of prochlorperazine is limited by its low solubility and inconsistent absorption in the gastrointestinal tract, which presents challenges for nanotherapeutic interventions. Here, we report the preparation of a highly soluble and permeable nanofiber formulation of prochlorperazine using the Quality-by-Design approach. The final nanofiber formulation with drug entrapment of 88.02 ± 1.14 % was obtained at 20.0 kV, with a flow rate of 0.5 ml/h and tip-to-collector distance of 19.9 cm. Physio-mechanical properties, such as thickness (0.42 ± 0.02 mm), pH resistance (7.04 ± 0.08), folding endurance (54 ± 5), and tensile strength (0.244 ± 0.02 N.mm-2), were appropriate for packaging and application to oromucosal surfaces. The content uniformity (93.48-106.63 %) and weight variation (<1.8 mg) of the optimal nanofiber formulation were within the permissible limits prescribed for orodispersible films. Microscopical investigations confirm a randomly deposited and dense network of woven nanofibers with an average diameter of 363 ± 5.66 nm. The drug particles were embedded homogeneously on the fiber in the nanoform (4.27 ± 1.34 nm). The spectral analysis using TEM-EDS shows diffraction peaks of sulfur and chlorine, the elemental constituents of prochlorperazine. The drug was amorphized in the nanofiber formulation, as led by the decline of the crystallinity index from 87.25 % to 7.93 % due to electrostatic destabilization and flash evaporation of the solvent. The enthalpy of fusion values of the drug in the nanofiber mat decreased significantly to 23.6 J/g compared to its pristine form, which exhibits a value of 260.7 J/g. The nanofibers were biocompatible with oral mucosal cells, and there were no signs of mucosal irritation compared to 1 % sodium lauryl sulfate. The fiber mats rapidly disintegrated within <1 s and released ≈91.49 ± 2.1 % of the drug within 2 min, almost 2-fold compared to the commercial Stemetil MD® tablets. Similarly, the cumulative amount of the drug permeated across the unit area of the oromucosal membrane was remarkably high (31.28 ± 1.30 µg) compared to 10.17 ± 1.11 µg and 13.10 ± 1.79 µg from the cast film and drug suspension. Our results revealed these nanofiber formulations have the potential to be fast-dissolving oromucosal delivery systems, which can result in enhanced bioavailability with an early onset of action due to rapid disintegration, dissolution, and permeation.


Assuntos
Nanofibras , Proclorperazina , Solubilidade
4.
Int J Biol Macromol ; 256(Pt 1): 128272, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38000568

RESUMO

Nanozymes, a new class of nanomaterials-based artificial enzymes, have gained huge attraction due to their high operational stability, working efficiency in extreme conditions, and resistance towards protease digestion. Nowadays, they are effectively substituted for natural enzymes for catalysis by closely resembling the active sites found in natural enzymes. Nanozymes can compensate for natural enzymes' drawbacks, such as high cost, poor stability, low yield, and storage challenges. Due to their transforming nature, nanozymes are of utmost importance in the detection and treatment of cancer. They enable precise cancer detection, tailored drug delivery, and catalytic therapy. Through enhanced diagnosis, personalized therapies, and reduced side effects, their adaptability and biocompatibility can transform the management of cancer. The review focuses on metal and metal oxide-based nanozymes, highlighting their catalytic processes, and their applications in the prevention and treatment of cancer. It emphasizes their potential to alter diagnosis and therapy, particularly when it comes to controlling reactive oxygen species (ROS). The article reveals the game-changing importance of nanozymes in the future of cancer care and describes future research objectives, making it a useful resource for researchers, and scientists. Lastly, outlooks for future perspective areas in this rapidly emerging field have been provided in detail.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Nanoestruturas/uso terapêutico , Nanoestruturas/química , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Endopeptidases , Peptídeo Hidrolases , Catálise
5.
Nanomaterials (Basel) ; 13(6)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36985895

RESUMO

Bacterial infections remain a serious and pervasive threat to human health. Bacterial antibiotic resistance, in particular, lowers treatment efficacy and increases mortality. The development of nanomaterials has made it possible to address issues in the biomedical, energy storage, and environmental fields. This paper reports the successful synthesis of CeO2-SnO2 composite nanofibers via an electrospinning method using polyacrylonitrile polymer. Scanning and transmission electron microscopy assessments showed that the average diameter of CeO2-SnO2 nanofibers was 170 nm. The result of photocatalytic degradation for methylene blue dye displayed enhanced efficiency of the CeO2-SnO2 composite. The addition of SnO2 to CeO2 resulted in the enhancement of the light absorption property and enriched charge transmission of photoinduced electron-hole duos, which conspicuously contributed to momentous photoactivity augmentation. Composite nanofibers exhibited higher specific capacitance which may be accredited to the synergism between CeO2 and SnO2 particles in nanofibers. Furthermore, antibacterial activity was screened against Escherichia coli and CeO2-SnO2 composite nanofibers depicted excellent activity. The findings of this work point to new possibilities as an electrode material in energy storage systems and as a visible-light-active photocatalyst for the purification of chemical and biological contaminants, which would substantially benefit environmental remediation processes.

6.
Nanoscale Adv ; 5(3): 742-755, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36756521

RESUMO

Glyphosate [N-(phosphonomethyl)glycine] is a widely used phosphonate herbicide for different agricultural purposes. Due to its widespread use, suspected toxicity, and ubiquitous bioaccumulation, it is one of the most harmful contaminants found in drinking water. This demands efficient sensing and removal of glyphosate from contaminated water. Here, we report the decoration of novel and highly porous biochar with nanozero-valent iron (nZVI) nanoparticles to develop an efficient electrochemical sensor for the trace detection of glyphosate. The as-synthesized composite was thoroughly characterized by various state-of-the-art instrumental techniques. The electron micrographs of the composite materials revealed the cavity-like structure and the abundant loading of nZVI nanoparticles. FTIR and XPS analyses confirmed the presence of oxygen-rich functionalities and Fe(0) in the composite nanostructure. Electrochemical analysis through CV, LSV, and DPV techniques suggested efficient sensing activity with a limit of detection as low as 0.13 ppm. Furthermore, the chronopotentiometric response suggested excellent and superior stability for long-term applications. To gain more insight into the interaction between glyphosate and the composite material, DFT calculations were carried out. The Frontier Molecular Orbital study (FMO), Molecular Electrostatic Potentials (MEPs), and Density of States (DOS) suggest an increase in the electron density, an increase in the DOS, and a decrease in the HOMO-LUMO band gap by combining nZVI nanoparticles and biochar. The results suggest more facile electron transfer from the composite for trace detection of glyphosate. As a proof of concept, we have demonstrated that real-time analysis of milk, apple juice, and the as-synthesized composite shows promising results for glyphosate detection with an excellent recovery rate.

7.
Biotechnol Bioeng ; 120(1): 22-40, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36169115

RESUMO

All the disciplines of science, especially biotechnology, have given continuous attention to the area of enzyme immobilization. However, the structural support made by material science intervention determines the performance of immobilized enzymes. Studies have proven that nanostructured supports can maintain better catalytic performance and improve immobilization efficiency. The recent trends in the application of nanofibers using natural polymers for enzyme immobilization have been addressed in this review article. A comprehensive survey about the immobilization strategies and their characteristics are highlighted. The natural polymers, e.g., chitin, chitosan, silk fibroin, gelatin, cellulose, and their blends with other synthetic polymers capable of immobilizing enzymes in their 1D nanofibrous form, are discussed. The multiple applications of enzymes immobilized on nanofibers in biocatalysis, biosensors, biofuels, antifouling, regenerative medicine, biomolecule degradation, etc.; some of these are discussed in this review article.


Assuntos
Técnicas Biossensoriais , Nanofibras , Enzimas Imobilizadas/metabolismo , Nanofibras/química , Polímeros/química , Biocatálise
8.
Int J Biol Macromol ; 226: 690-705, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36513179

RESUMO

In this study, polyurethane (PU) and cellulose acetate (CA) electrospun fibers encapsulating rosemary essential oil (REO) and adsorbed silver (Ag) nanoparticles (NPs) were fabricated. The biologically inspired materials were analyzed for physicochemical characteristics using scanning electron microscopy, X-ray diffractometer, Fourier transform infrared, thermal gravimetric analysis, X-ray photoelectron spectroscopy, water contact angle, and water uptake studies. Results confirmed the presence of CA and Ag NPs on the PU micro-nanofibers increased the hydrophilicity from 107.1 ± 0.36o to 26.35 ± 1.06o. The water absorption potential increased from 0.07 ± 0.04 for pristine PU fibers to 12.43 ± 0.49 % for fibers with 7 wt% of CA, REO, and Ag NPs. The diffractometer confirmed the 2θ of 38.01°, 44.13o, and 64.33o, corresponding to the diffraction planes of Ag on the fibers. The X-ray photoelectron spectroscopy confirmed microfibers interfacial chemical interaction and surface changes due to CA, REO, and Ag presence. The inhibition tests on Staphylococcus aureus and Escherichia coli indicated that composites are antibacterial in activity. Moreover, synergistic interactions of REO and Ag NPs resulted in superior antibacterial activity. The cell viability and attachment assay showed improved hydrophilicity of the fibers, which resulted in better attachment of cells to the micro-nanofibers, similar to the natural extracellular matrix in the human body.


Assuntos
Nanopartículas Metálicas , Nanofibras , Óleos Voláteis , Rosmarinus , Humanos , Poliuretanos , Prata/química , Nanopartículas Metálicas/química , Nanofibras/química , Antibacterianos/farmacologia , Antibacterianos/química , Óleos Voláteis/farmacologia , Cicatrização
9.
AAPS PharmSciTech ; 23(5): 160, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35676602

RESUMO

Prolonged retention of losartan potassium in the upper gastrointestinal tract is anticipated to increase its absorption and exposure to CYP450 enzyme subfamilies, undertaking its conversion to more potent (10-40 times) active metabolite, losartan carboxylic acid (LCA). Consistent with this, hydroxypropyl methylcellulose K4M/ethyl cellulose-based novel expandable films (EFs) containing losartan potassium (LP) suitable for prolonged retention in the stomach were developed. The films were prepared by solvent casting method. USP type II dissolution apparatus (0.1 N HCl, 37°C, 100 rpm) was used to perform the dissolution testing (drug release, unfolding behavior, film integrity, erosion, and water uptake) of the films. In vivo pharmacokinetic studies were carried out in rabbits. An HPLC-UV method was used for the quantification of the drug and its active metabolite in plasma. These folded films placed inside hard gelatin capsule shells unfolded to full dimensions in dissolution medium and provided sustained drug release throughout 12 h. The plasma drug concentration-time curves obtained from the in vivo studies were used to determine pharmacokinetic parameters, such as area under the plasma drug concentration-time curve (AUC), area under first moment curve (AUMC), mean residence time (MRT), Cmax, Tmax, t1/2, ke, and Fr in comparison with that of the market formulation, Cozaar®. The novel EFs significantly changed the pharmacokinetic parameters of the drug and its active metabolite. The apparent elimination rate constant (ke) significantly decreased, while MRT and elimination half-life (t1/2) increased in both cases. The relative bioavailabilities (Fr) of both LP and E3174 using the novel formulation were higher than that of Cozaar®.


Assuntos
Celulose , Losartan , Animais , Disponibilidade Biológica , Celulose/análogos & derivados , Preparações de Ação Retardada/farmacocinética , Losartan/farmacocinética , Coelhos
10.
Biotechnol Bioeng ; 119(1): 9-33, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34672360

RESUMO

The arrangement and type of support has a significant impact on the efficiency of immobilized enzymes. 1-dimensional fibrous materials can be one of the most desirable supports for enzyme immobilization. This is due to their high surface area to volume ratio, internal porosity, ease of handling, and high mechanical stability, all of which allow a higher enzyme loading, release and finally lead to better catalytic efficiency. Fortunately, the enzymes can reside inside individual nanofibers to remain encapsulated and retain their three-dimensional structure. These properties can protect the enzyme's tolerance against harsh conditions such as pH variations and high temperature, and this can probably enhance the enzyme's stability. This review article will discuss the immobilization of enzymes on synthetic polymers, which are fabricated into nanofibers by electrospinning. This technique is rapidly gaining popularity as one of the most practical ways to fibricate polymer, metal oxide, and composite micro or nanofibers. As a result, there is interest in using nanofibers to immobilize enzymes. Furthermore, present research on electrospun nanofibers for enzyme immobilization is primarily limited to the lab scale and industrial scale is still challanging. The primary future research objectives of this paper is to investigate the use of electrospun nanofibers for enzyme immobilization, which includes increasing yield to transfer biological products into commercial applications.


Assuntos
Biocatálise , Técnicas Eletroquímicas/métodos , Enzimas Imobilizadas , Nanofibras/química , Polímeros , Enzimas Imobilizadas/química , Enzimas Imobilizadas/metabolismo , Polímeros/química , Polímeros/metabolismo
11.
J Control Release ; 339: 143-155, 2021 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-34563589

RESUMO

Bone development is a complex process involving a vast number of growth factors and chemical substances. These factors include transforming growth factor-beta, platelet-derived growth factor, insulin-like growth factor, and most importantly, the bone morphogenetic protein, which exhibits excellent therapeutic value in bone repair. However, the spatial-temporal relationship in the expression of these factors during bone formation makes the bone repair a more complicated process to address. Thus, using a single therapeutic agent to address bone formation does not seem to provide a clinically effective option. Conversely, a dual delivery approach facilitating the co-delivery of agents has proved to be a dynamic alternative since such a strategy can provide more efficient spatial-temporal action. Such delivery systems can smartly target more than one pathway or differentiation lineage and thus offer more efficient bone regeneration. This review discusses various dual delivery strategies reported in the literature employed to achieve improved bone regeneration. These include concurrent use of different therapeutic agents (including growth factors and drugs), enhancing bone formation and cell recruitment, and improving the efficiency of bone healing.


Assuntos
Materiais Biocompatíveis , Proteína Morfogenética Óssea 2 , Regeneração Óssea , Osso e Ossos , Osteogênese
12.
Int J Mol Sci ; 22(8)2021 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-33924640

RESUMO

Essential oils prevent superbug formation, which is mainly caused by the continuous use of synthetic drugs. This is a significant threat to health, the environment, and food safety. Plant extracts in the form of essential oils are good enough to destroy pests and fight bacterial infections in animals and humans. In this review article, different essential oils containing polymeric nanofibers fabricated by electrospinning are reviewed. These nanofibers containing essential oils have shown applications in biomedical applications and as food-packaging materials. This approach of delivering essential oils in nanoformulations has attracted considerable attention in the scientific community due to its low price, a considerable ratio of surface area to volume, versatility, and high yield. It is observed that the resulting nanofibers possess antimicrobial, anti-inflammatory, and antioxidant properties. Therefore, they can reduce the use of toxic synthetic drugs that are utilized in the cosmetics, medicine, and food industries. These nanofibers increase barrier properties against light, oxygen, and heat, thereby protecting and preserving the food from oxidative damage. Moreover, the nanofibers discussed are introduced with naturally derived chemical compounds in a controlled manner, which simultaneously prevents their degradation. The nanofibers loaded with different essential oils demonstrate an ability to increase the shelf-life of various food products while using them as active packaging materials.


Assuntos
Embalagem de Alimentos , Nanofibras/química , Óleos Voláteis/química , Polímeros/química , Animais , Composição de Medicamentos , Humanos , Nanofibras/ultraestrutura , Alicerces Teciduais/química
13.
Mater Sci Eng C Mater Biol Appl ; 118: 111547, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33255098

RESUMO

Cellulose nanofibers, which are troublesome to spin into fibers, can be easily fabricated by post-regeneration of its acetate-derived threads. Cellulose is a natural polymer; it enjoys better biocompatibility, cellular mimicking, and hydrophilic properties than its proportionate analog. Herein, we regenerated acetate-free nanofibers by alkaline de-acetylation of as-spun nanofibers. The resultant cellulose nanofibers previously loaded with hydroxyapatite (HAp) were immobilized using silver (Ag) nanoparticles (NPs) by reduction of adsorbed Ag ions on using sodium borohydride. These amalgamated nanofibers were characterized for SEM, EDX, TEM, FTIR, and hydrophilicity tests revealing the existence of both HAp and Ag NPs in/on the nanofiber scaffolds. The de-acetylation of composite nanofibers resulted in spontaneous hydrophilicity. These nanofibers were cytocompatible, as resolved by MTT assay conducted on chicken embryo fibroblasts. The SEM of the samples after cell culture revealed that these composites allowed a proliferation of the fibroblasts over and within the nanofiber network, and increased concentration of HAp levitated the excessive of apatite formation as well as increased cell growth. The antimicrobial activity of these nanofibers was assessed on E. coli (BL21) and S. aureus, suggesting the potential of de-acetylated nanofibers to restrain bacterial growth. The degradation study for 10, 30, and 60 days indicated degradation of the fibers much is faster in enzymes as compared to degradation in PBS. The results certify that these nanofibers possess enormous potential for soft and hard tissue engineering besides their antimicrobial properties.


Assuntos
Nanofibras , Nanopartículas , Animais , Celulose/análogos & derivados , Embrião de Galinha , Durapatita , Escherichia coli , Prata/farmacologia , Staphylococcus aureus , Engenharia Tecidual
14.
Curr Pharm Biotechnol ; 22(6): 793-807, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33176640

RESUMO

Carbon nanotubes are nano-sized cylindrical chicken wire-like structures made of carbon atoms. Carbon nanotubes have applications in electronics, energy storage, electromagnetic devices, environmental remediation and medicine as well. The biomedical applications of carbon nanotubes can be owed to features like low toxicity, non-immunogenicity, high in vivo stability and rapid cell entry. Carbon nanotubes have a great prospect in the treatment of diseases through diagnostic as well as therapeutic approaches. These nanostructures are interesting carriers for delivery and translocation of therapeutic molecules e.g. proteins, peptides, nucleic acids, drugs, etc. to various organs like the brain, lungs, liver, and pancreas. Commonly used methods to synthesize carbon nanotubes are arc discharge, chemical vapor deposition, pyrolysis, laser ablation etc. These methods have many disadvantages such as operation at high temperature, use of chemical catalysts, prolonged synthesis time and inclusion of toxic metallic particles in the final product requiring additional purification processes. In order to avoid these setbacks, various green chemistry-based synthetic methods have been devised, e.g., those involving interfacial polymerization, supercritical carbon dioxide drying, plant extract assisted synthesis, water- assisted synthesis, etc. This review will provide a thorough outlook of the eco-friendly synthesis of carbon nanotubes reported in the literature and their biomedical applications. Besides, the most commonly used spectroscopic techniques used for the characterization of carbon nanotubes are also discussed.


Assuntos
Portadores de Fármacos/química , Nanotubos de Carbono/química , Extratos Vegetais/química , Polimerização
15.
Macromol Rapid Commun ; 41(21): e2000195, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32529701

RESUMO

The present paper describes the addition of nitroxide-functionalized graphene oxide (GOFT) into polyamide 6 (PA6) micro- and nanofibers, which are obtained through electrospinning. Scanning electron microscopy micrographs demonstrate the presence of fibers. Tensile testing presents an unexpected and non-obvious behavior, in which the Young's modulus, tensile strength, and elongation simultaneously and remarkably increase compared to the pristine polymer nanofibers. GOFT induces the hydrogen bonding between the NH group from PA6 with the functional groups, thus promoting higher crystallinity of the polymer matrix. Nonetheless, deconvoluted curves by differential scanning calorimetry reveal the presence of two quasi-steady polymorphs (ß and Î´ phases) contributing to 46% of the total crystallinity. This evidence suggests that their presence and high ratios are responsible for the unexpected and simultaneous enhancement of tensile properties.


Assuntos
Nanofibras , Nylons , Caprolactama/análogos & derivados , Grafite , Polímeros
16.
Mater Sci Eng C Mater Biol Appl ; 111: 110756, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32279775

RESUMO

Transmucosal surfaces bypass many limitations associated with conventional drug delivery (oral and parenteral routes), such as poor absorption rate, enzymatic activity, acidic environment and first-pass metabolism occurring inside the liver. However, these surfaces have several disadvantages such as poor retention time, narrow absorption window and continuous washout of the drug by the surrounding fluids. Electrospun nanofibers with their unique surface properties and encapsulation efficiency may act as novel drug carriers to overcome the challenges associated with conventional drug delivery routes, so as to achieve desired therapeutic responses. This review article provides detailed information regarding the challenges faced in the mucosal delivery of drugs, and the use of nanofiber systems as an alternative to deliver drugs to the systemic circulation, as well as local drug administration. The physiological and anatomical features of different types of mucosal surfaces and current challenges are systematically discussed. We also address future considerations in the area of transmucosal delivery of some important drugs.


Assuntos
Portadores de Fármacos/química , Nanofibras/química , Preparações Farmacêuticas/química , Portadores de Fármacos/metabolismo , Feminino , Humanos , Mucosa Bucal/metabolismo , Mucosa Nasal/metabolismo , Preparações Farmacêuticas/metabolismo , Polímeros/química , Vagina/metabolismo
17.
J Biomed Mater Res A ; 108(4): 947-962, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31894888

RESUMO

In the present work, a novel strategy was explored to fabricate nanofiber scaffolds consisting of cellulose assimilated with titanium dioxide (TiO2 ) and silver (Ag) nanoparticles (NPs). The concentration of the TiO2 NPs in the composite was adjusted to 1.0, 1.5, and 2.0 wt % with respect to polymer concentration used for the electrospinning of colloidal solutions. The fabricated composite scaffolds were dispensed to alkaline deacetylation using 0.05 M NaOH to remove the acetyl groups in order to generate pure cellulose nanofibers containing TiO2 NPs. Moreover, to augment our nanofiber scaffolds with antibacterial activity, the in situ deposition approach of using Ag NPs was utilized with varied molar concentrations of 0.14, 0.42, and 0.71 M. The physicochemical properties of the nanofibers were identified by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and contact angle meter studies. This demonstrated the presence of both TiO2 and Ag NPs and complete deacetylation of nanofibers. The antibacterial efficiency of the nanofibers was scrutinized against Escherichia coli and Staphylococcus aureus, revealing proper in situ deposition of Ag NPs and confirming the nanofibers are antibacterial in nature. The biocompatibility of the scaffolds was accustomed using chicken embryo fibroblasts, which confirmed their potential role to be used as wound-healing materials. Furthermore, the fabricated scaffolds were subjected to analysis in simulated body fluid at 37°C to induce mineralization for future osseous tissue integration. These results indicate that fabricated composite nanofiber scaffolds with multifunctional characteristics will have a highest potential as a future candidate for promoting new tissues artificially.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/farmacologia , Celulose/farmacologia , Nanofibras/química , Prata/farmacologia , Engenharia Tecidual , Alicerces Teciduais/química , Titânio/farmacologia , Acetilação/efeitos dos fármacos , Animais , Calcificação Fisiológica/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Durapatita/química , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Interações Hidrofóbicas e Hidrofílicas , Testes de Sensibilidade Microbiana , Nanofibras/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier
18.
Methods Mol Biol ; 2125: 95-108, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31004285

RESUMO

Nanofibrous structures provide a three-dimensional topography in vivo to allow the attachment, migration, proliferation, and differentiation of the cells in an environment which exactly mimics the native tissue. Herein, we report the standard protocols to carry out the cell culture of human osteoblast on nanofiber scaffolds. We also have described protocols for the determination of cell viability, morphology, mineralization, and phenotypic characterization of the osteoblasts.


Assuntos
Técnicas de Cultura de Células/métodos , Diferenciação Celular , Imageamento Tridimensional , Nanofibras/química , Osteoblastos/citologia , Alicerces Teciduais/química , Calcificação Fisiológica , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Humanos , Fenótipo
19.
Methods Mol Biol ; 2125: 109-117, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31020638

RESUMO

The treatment of neurodegenerative diseases is still a challenging grindstone in reconstructive surgeries and regenerative medicine. The retention of mesenchymal stem cells (MSCs) to retain remarkable properties of differentiating into motor neuron-like cells and Schwann cells can prove to be effective in repairing disorders. Moreover, the ultrafine electrospun nanofibers provide a favorable and conducive platform for proliferation and differentiation of MSCs. The development of new 3D culture methods with electrospun scaffolds that closely mimic the physiological niche of cells will help us to understand the functional benefits of MSCs in regeneration process. This article highlights the protocols for isolation of MSCs from rat bone marrow and their subsequent culture on nanofiber scaffolds. Furthermore, this chapter summarizes the various procedures including isolation of the MSCs, their seeding on electrospun nanofibrous scaffolds, and their proliferation and differentiation into neural lineage upon appropriate induction. The materials and preparation of various reagents used at different steps of the protocol are also summarized in detail.


Assuntos
Técnicas de Cultura de Células/métodos , Diferenciação Celular , Linhagem da Célula , Células-Tronco Mesenquimais/citologia , Regeneração Nervosa , Neurônios/citologia , Polímeros/química , Alicerces Teciduais/química , Animais , Separação Celular , Sobrevivência Celular , Células Cultivadas , Ratos , Reação em Cadeia da Polimerase em Tempo Real
20.
Methods Mol Biol ; 2125: 77-84, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31392588

RESUMO

Therapy based on stem cells utilizes these cells in neurodegeneration, brain/spinal cord injury, and much recently in repairing of severe heart diseases. Owning to their stemness, these cells are the potential source of progenitors that can offer a therapeutic remedy to a variety of diseases and/or disorders. The ability of these cells to regenerate and differentiate into specified phenotypes has great utility in tissue regeneration applications. This chapter provides a detailed account for isolation of neural stem cells from the mice embryo. Furthermore, the fabrication of chitosan-tripolyphosphate/hyaluronic acid-based nanoparticles and evaluating their efficiency in inducing transfection in the isolated neural stem cells as an approach for the treatment of neurodegenerative disorders.


Assuntos
Expressão Gênica , Nanopartículas/química , Nanotecnologia/métodos , Células-Tronco Neurais/metabolismo , Polímeros/química , Transgenes , Animais , Morte Celular , Células Cultivadas , Quitosana/análogos & derivados , Quitosana/química , Criopreservação , DNA/genética , Ácido Hialurônico/química , Camundongos , Células-Tronco Neurais/citologia , Plasmídeos/genética , Transfecção
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