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1.
Nanocarriers, in various forms, have the possibility of providing endless opportunities in the area of drug delivery. The purpose of this study was formulation and evaluation of betamethasone sodium phosphate (BSP) loaded chitosan nanoparticles (CNPs) using cross‐linked chitosan malic acid derivative for better therapeutic effect. The prepared BSP loaded CNPs formulations were characterised for photon correlation spectroscopy, zeta potential, transmission electron microscopy, in‐vitro release kinetics and in‐vivo toxicity studies. Mean particle diameter of BSP loaded CNPs was about 130 nm with spherical morphology. The in‐vitro drug release study of BSP loaded CNPs showed sustained drug release for 48 h and drug release was found to follow zero order. The biochemical, haematology and histopathology reports of in‐vivo toxicity studies revealed that BSP loaded CNPs do not exhibit any toxic effect on vital organs and could be safe. The developed BSP loaded CNPs are found to be safer, and used for the treatments of highly prevalent and chronic disease like rheumatoid arthritis.Inspec keywords: nanoparticles, drug delivery systems, electrokinetic effects, toxicology, photon correlation spectroscopy, transmission electron microscopy, diseases, organic compounds, nanomedicineOther keywords: betamethasone sodium phosphate, chitosan nanoparticles, antirheumatoid activity, nanocarriers, drug delivery, cross‐linked chitosan malic acid derivative, photon correlation spectroscopy, zeta potential, transmission electron microscopy, in‐vitro release kinetics, in‐vivo toxicity, spherical morphology, rheumatoid arthritis  相似文献   

2.
Drug encapsulation in nanocarriers such as polymeric nanoparticles (Nps) may help to overcome the limitations associated with cannabinoids. In this study, the authors’ work aimed to highlight the use of electrospraying techniques for the development of carrier Nps of anandamide (AEA), an endocannabinoid with attractive pharmacological effects but underestimated due to its unfavourable physicochemical and pharmacokinetic properties added to its undesirable effects at the level of the central nervous system. The authors characterised physicochemically and evaluated in vitro biological activity of anandamide/ɛ‐polycaprolactone nanoparticles (Nps‐AEA/PCL) obtained by electrospraying in epithelial cells of the human proximal tubule (HK2), to prove the utility of this method and to validate the biological effect of Nps‐AEA/PCL. They obtained particles from 100 to 900 nm of diameter with a predominance of 200–400 nm. Their zeta potential was −20 ± 1.86 mV. They demonstrated the stable encapsulation of AEA in Nps‐AEA/PCL, as well as its dose‐dependent capacity to induce the expression of iNOS and NO levels and to decrease the Na+ /K+ ATPase activity in HK2 cells. Obtaining Nps‐AEA/PCL by electrospraying would represent a promising methodology for a novel AEA pharmaceutical formulation development with optimal physicochemical properties, physical stability and biological activity on HK2 cells.Inspec keywords: cellular biophysics, molecular biophysics, nanoparticles, nanofabrication, biochemistry, encapsulation, drugs, neurophysiology, electrokinetic effects, enzymes, biomedical materials, nanomedicine, polymers, sprayingOther keywords: electrospraying techniques, pharmacological effects, pharmacokinetic properties, in vitro biological activity, biological effect, HK2 cells, optimal physicochemical properties, polymeric nanoparticles, AEA pharmaceutical formulation development, anandamide‐ε‐polycaprolactone nanoparticles, drug encapsulation, nanocarriers, endocannabinoid, central nervous system, epithelial cells, human proximal tubule, zeta potential, stable encapsulation, dose‐dependent capacity, Na+ ‐K+ ATPase activity, physical stability, size 100.0 nm to 900.0 nm, NO, Na+ ‐K+   相似文献   

3.
Silver nanoparticles (AgNPs) have shown potential applications in drug delivery. In this study, the AgNPs was prepared from silver nitrate in the presence of alginate as a capping agent. The ciprofloxacin (Cipro) was loaded on the surface of AgNPs to produce Cipro‐AgNPs nanocomposite. The characteristics of the Cipro‐AgNPs nanocomposite were studied by X‐ray diffraction (XRD), UV–Vis, transmission electron microscopy (TEM), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), Fourier‐transform infra‐red analysis (FT‐IR) and zeta potential analyses. The XRD of AgNPs and Cipro‐AgNPs nanocomposite data showed that both have a crystalline structure in nature. The FT‐IR data indicate that the AgNPs have been wrapped by the alginate and loaded with the Cipro drug. The TEM image showed that the Cipro‐AgNPs nanocomposites have an average size of 96 nm with a spherical shape. The SEM image for AgNPs and Cipro‐AgNPs nanocomposites confirmed the needle‐lumpy shape. The zeta potential for Cipro‐AgNPs nanocomposites exhibited a positive charge with a value of 6.5 mV. The TGA for Cipro‐AgNPs nanocomposites showed loss of 79.7% in total mass compared to 57.6% for AgNPs which is due to the Cipro loaded in the AgNPs. The release of Cipro from Cipro‐AgNPs nanocomposites showed slow release properties which reached 98% release within 750 min, and followed the Hixson–Crowell kinetic model. In addition, the toxicity of AgNPs and Cipro‐AgNPs nanocomposites was evaluated using normal (3T3) cell line. The present work suggests that Cipro‐AgNPs are suitable for drug delivery.  相似文献   

4.
This paper aims to investigate the preparation and characterisation of the alginate nanoparticles (NPs) as antigen delivery system loaded by diphtheria toxoid (DT). For this purpose, both the loading capacity (LC) and Loading efficiency (LE) of the alginate NPs burdened by DT are evaluated. Moreover, the effects of different concentrations of sodium alginate and calcium chloride on the NPs physicochemical characteristics are surveyed in addition to other physical conditions such as homogenization time and rate. To do so, the NPs are characterised using particle size and distribution, zeta potential, scanning electron microscopy, encapsulation efficiency, in vitro release study and FT‐IR spectroscopy. Subsequently, the effects of homogenization time and rate on the NPs are assessed. At the meantime, the NPs LC and efficiency in several DT concentrations are estimated. The average size of the NPs was 400.7 and 276.6 nm for unloaded and DT loaded, respectively. According to the obtained results, the zeta potential of the blank and DT loaded NPs are estimated as −23.7 mV and −21.2 mV, respectively. Whereas, the LC and LE were >80% and >90%, in that order. Furthermore, 95% of the releasing DT loaded NPs occurs at 140 h in the sustained mode without any bursting release. It can be concluded that the features of NPs such as morphology and particle size are strongly depended on the calcium chloride, sodium alginate concentrations and physicochemical conditions in the NPs formation process. In addition, appropriate concentrations of the sodium alginate and calcium ions would lead to obtaining the desirable NPs formation associated with the advantageous LE, LC (over 80%) and sustained in vitro release profile. Ultimately, the proposed NPs can be employed in vaccine formulation for the targeted delivery, controlled and slow antigen release associated with the improved antigen stability.  相似文献   

5.
Based on the enhancement of synergistic antitumour activity to treat cancer and the correlation between inflammation and carcinogenesis, the authors designed chitosan nanoparticles for co‐delivery of 5‐fluororacil (5‐Fu: an as anti‐cancer drug) and aspirin (a non‐steroidal anti‐inflammatory drug) and induced synergistic antitumour activity through the modulation of the nuclear factor kappa B (NF‐κB)/cyclooxygenase‐2 (COX‐2) signalling pathways. The results showed that aspirin at non‐cytotoxic concentrations synergistically sensitised hepatocellular carcinoma cells to 5‐Fu in vitro. It demonstrated that aspirin inhibited NF‐κB activation and suppressed NF‐κB regulated COX‐2 expression and prostaglandin E2 (PGE2) synthesis. Furthermore, the proposed results clearly indicated that the combination of 5‐Fu and aspirin by chitosan nanoparticles enhanced the intracellular concentration of drugs and exerted synergistic growth inhibition and apoptosis induction on hepatocellular carcinoma cells by suppressing NF‐κB activation and inhibition of expression of COX‐2.Inspec keywords: proteins, molecular biophysics, cellular biophysics, biomedical materials, cancer, nanoparticles, drug delivery systems, enzymes, tumours, nanomedicine, drugsOther keywords: chitosan nanoparticles, aspirin, 5‐fluororacil, synergistic antitumour activity, anticancer drug, nonsteroidal antiinflammatory drug, hepatocellular carcinoma cells, NF‐κB activation, NF‐κB regulated COX‐2 expression, PGE2, synergistic growth inhibition, apoptosis induction, prostaglandin E2 synthesis, intracellular concentration, noncytotoxic concentrations, NF‐κB‐cyclooxygenase‐2 signalling pathways, cyclooxygenase‐2, nuclear factor kappa B  相似文献   

6.
Bio‐ synthesis of silver nanoparticles (AgNPs) was made by using the aqueous leaf extract of Ardisia solanacea. Rapid formation of AgNPs was observed from silver nitrate upon treatment with the aqueous extract of A. solanacea leaf. The formation and stability of the AgNPs in the colloidal solution were monitored by UV–visible spectrophotometer. The mean particle diameter of AgNPs was calculated from the DLS with an average size ∼4 nm and ∼65 nm. ATR‐FTIR spectroscopy confirmed the presence of alcohols, aldehydes, flavonoids, phenols and nitro compounds in the leaf which act as the stabilizing agent. Antimicrobial activity of the synthesized AgNPs was performed using agar well diffusion and broth dilution method against the Gram‐positive and Gram‐negative bacteria. Further, robust anti‐oxidative potential was evaluated by DPPH assay. The highest antimicrobial activity of synthesized AgNPs was found against Pseudomonas aeruginosa (28.2 ± 0.52 mm) whereas moderate activity was found against Bacillus subtilis (16.1 ± 0.76), Candida kruseii (13.0 ± 1.0), and Trichophyton mentagrophytes (12.6 ± 1.52). Moreover, the potential wound healing activity was observed against the BJ‐5Ta normal fibroblast cell line. Current research revealed that A. solanacea was found to be a suitable source for the green synthesis of silver nanoparticles.Inspec keywords: antibacterial activity, nanoparticles, silver, nanomedicine, wounds, microorganisms, X‐ray diffraction, ultraviolet spectra, visible spectra, Fourier transform infrared spectra, transmission electron microscopyOther keywords: phyto‐assisted synthesis, biofunctionalised silver nanoparticles, antioxidant antimicrobial wound healing activities, silver nanoparticle biosynthesis, aqueous leaf extract, Ardisia solanacea, silver nitrate, UV–visible spectroscopy, dynamic light scattering, Fourier transform infra‐red spectroscopy, X‐ray diffraction, electron microscopy, attenuated total reflection Fourier transform infra‐red spectroscopy, dilution method, Gram‐positive bacteria, Gram‐negative bacteria, radical scavenging method, Pseudomonas aeruginosa, Trichophyton mentagrophytes, Bacillus subtilis, Candida kruseii, BJ‐5Ta normal fibroblast cell line, SEM, alcohols, aldehydes, flavonoids, phenols, nitro compounds, Ag  相似文献   

7.
Mastitis is an important economic disease causing production losses in dairy industry. Antibiotics are becoming ineffective in controlling mastitis due to the emergence of resistant strains requiring the development of novel therapeutic agents. In this study, the authors present the phytochemical synthesis of silver nanoparticles (AgNPs) with acetyl‐11‐α‐keto‐β‐boswellic acid and evaluation of their activity in Staphylococcus aureus induced murine mastitis. Boswellic acid mediated AgNP (BANS) were oval, polydispersed (99.8 nm) with an minimum inhibitory concentration of 0.033 µg ml−1 against S. aureus, inhibitory concentration (IC50) of 30.04 µg ml−1 on mouse splenocytes and safe at an in vivo acute oral dose of 3.5 mg kg−1 in mice. Mastitis was induced in lactating mice by inoculating S. aureus (log10 5.60 cfu) and treated 6 h post‐inoculation with BANS (0.12 mg kg−1, intramammary and intraperitoneal), and cefepime (1 mg kg−1, intraperitoneal). S. aureus inoculated mice showed increased bacterial load, neutrophil infiltration in mammary glands and elevated C‐reactive protein (CRP) in serum. Oxidative stress was also observed with elevated malondialdehyde level, superoxide dismutase (SOD) and catalase (CAT) activities. BANS treatment significantly (P  < 0.05) reduced bacterial load, CRP, SOD, CAT activities and neutrophil infiltration in affected mammary glands. BANS could be a potential therapeutic agent for managing bovine mastitis.Inspec keywords: nanomedicine, nanoparticles, silver, antibacterial activity, drugs, diseases, enzymesOther keywords: antibacterial effects, antiinflammatory effects, antioxidant effects, acetyl‐11‐α‐keto‐β‐boswellic acid, mediated silver nanoparticles, experimental murine mastitis, economic disease, dairy industry, resistant strains, phytochemical synthesis, Staphylococcus aureus, minimum inhibitory concentration, inoculating S. aureus, neutrophil infiltration, mammary glands, elevated C‐reactive protein, superoxide dismutase, catalase, bovine mastitis, Ag  相似文献   

8.
Breast cancer is a major cause of cancer mortality. Regarding the advantages of polymeric nanoparticles as drug delivery systems with targeting potential, in this study the antitumor mechanism of targeted docetaxel polymeric nanoparticles of Ecoflex® was exploited. Since the overexpression of HER‐2 receptor in breast cancer cases is associated with poor prognosis and more aggressive disease, the proposed nanoparticles were conjugated to HER‐2 specific aptamer molecules. In vitro cytotoxicity was evaluated by MTT assay. Flow‐cytometry analysis was performed to evaluate the cellular uptake of nanoparticles loaded with a fluorescent probe. Anti‐migration effects of samples were studied. Annexin IV‐FITC and propidium iodide were implemented to investigate apoptosis induction and cell cycle analysis. Enhanced cytotoxicity compared with free docetaxel was explained considering improved cellular uptake of the nanoparticles and induced apoptosis in a larger portion of cells. Lower relative migration demonstrated enhanced anti‐migration effect of nanoparticles, and cell cycle was arrested in G2/M phase using both formulations so the anti‐microtubule mechanism of the drug was not altered. Therefore, this system could offer a potential substitute for the currently marketed docetaxel formulations, which may reduce adverse effects of the drug, while further in vivo and clinical investigations are required.Inspec keywords: cancer, molecular biophysics, drug delivery systems, fluorescence, biomedical materials, drugs, tumours, nanomedicine, proteins, toxicology, biochemistry, nanoparticles, diseases, cell motility, polymersOther keywords: antitumor mechanism, targeted docetaxel polymeric nanoparticles, HER‐2 specific aptamer molecules, MTT assay, flow‐cytometry analysis, annexin IV‐FITC, apoptosis induction, cell cycle, lower relative migration, cancer mortality, drug delivery systems, aggressive disease, in vitro cytotoxicity, cellular uptake, breast cancer cell apoptosis, antimetastatic effect, HER‐2 aptamer‐targeted Ecoflex nanoparticles, antimigration effect, antimicrotubule mechanism, HER‐2 receptor, fluorescent probe, propidium iodide  相似文献   

9.
Developing nanostructures for cancer treatment is growing significantly. Liposomal doxorubicin is a drug that is used in the clinic and represents a lot of benefits over doxorubicin. The development of multifunctional liposomes with different cancer treatment capability enables broader applications of doxorubicin chemotherapy. Many efforts were carried to prepare more effective liposomal formulation through loading gold nanoparticles (GNPs) in the formulation. Here, GNPs with an average size of 6 nm were loaded in liposomal formulation alongside doxorubicin. The hydrodynamic diameter of final formulation was 177.3 ± 33.9 nm that in comparison with liposomes without GNPs (112.5 ± 10.3 nm), GNPs‐loaded liposomes showed the bigger hydrodynamic diameter. GNPs‐loaded liposomes are slightly positively charged (4.4 ± 1.1 mV), while liposomes without loading the GNPs were negatively charged (−18.5 ± 1.6 mV). Doxorubicin was loaded in this formulation through active loading technique. Doxorubicin loading efficiency in gold‐loaded liposomes is slightly lesser than liposomes without GNPs, but still considerably high in comparison to passive loading techniques.Inspec keywords: nanofabrication, drugs, nanomedicine, gold, cancer, lipid bilayers, drug delivery systems, nanoparticles, crystal growth from solutionOther keywords: liposomal doxorubicin, multifunctional liposomes, doxorubicin chemotherapy, active loading technique, doxorubicin loading efficiency, gold‐loaded liposomes, passive loading techniques, gold nanoparticles, cancer treatment, liposomal formulation, GNP‐loaded liposomes, hydrodynamic diameter  相似文献   

10.
Due to the strong effect of nanoparticles'' size and surface properties on cellular uptake and bio‐distribution, the selection of coating material for magnetic core–shell nanoparticles (CSNPs) is very important. In this study, the effects of four different biocompatible coating materials on the physical properties of Fe3 O4 (magnetite) nanoparticles (NPs) for different biomedical applications are investigated and compared. In this regard, magnetite NPs are prepared by a simple co‐precipitation method. Then, CSNPs including Fe3 O4 as a core and carbon, dextran, ZnO (zincite) and SiO2 (silica) as different shells are synthesised using simple one‐ or two‐step methods. A comprehensive study is carried out on the prepared samples using X‐ray diffraction, vibrating sample magnetometry, transmission electron microscopy and Fourier transform infrared spectroscopy analyses. According to the authors'' findings, it is suggested that carbon‐ and dextran‐coated magnetite NPs with high M s have great potential in the application of magnetic resonance imaging contrast agents. Moreover, silica‐coated magnetite NPs with high coercivity are potentially suitable candidates for hyperthermia and ZnO‐coated Fe3 O4 is potentially suitable for photothermal therapy.Inspec keywords: iron compounds, carbon, silicon compounds, zinc compounds, nanomedicine, biomedical materials, nanofabrication, nanoparticles, magnetic particles, coatings, X‐ray diffraction, magnetometry, transmission electron microscopy, Fourier transform spectra, infrared spectra, biomedical MRI, hyperthermia, radiation therapyOther keywords: biomedical applications, magnetic core‐shell nanoparticles, CSNP, cellular uptake, biodistribution, coating material, biocompatible coating materials, co‐precipitation, dextran, zincite, silica, X‐ray diffraction, vibrating sample magnetometry, transmission electron microscopy, Fourier transform infrared spectroscopy, magnetic resonance imaging contrast agents, hyperthermia, photothermal therapy, SiO2 ‐Fe3 O4 , ZnO‐Fe3 O4   相似文献   

11.
Biodegradable polymers have greatly promoted the development of environmental, biomedical and allied sciences because of their biocompatibility and doping chemistry. The emergence of nanotechnology has envisaged greater options for the development of biodegradable materials. Polyaniline grafted chitosan (i.e. biodegradable PANI) copolymer was prepared by the chemical in situ polymerisation of aniline using ammonium per sulphate as initiator while Ag nanoparticle were synthesised by chemical reduction method and incorporated in to the polymer matrix. The as prepared materials were characterised by X‐ray diffraction, Fourier transform Infra‐red spectroscopy, transmission electron microscopy, energy dispersive X‐ray analysis. Moreover energy storage capacity, impedance properties were also studied. The main focus was on the photocatalytic degradation of organic dyes to remove the toxic and carcinogenic pollutants. This polymer nano‐biocomposite has multifold applications and can be used as excellent materials for enhanced photodegradation and removal of toxic contaminants from waste waters and natural water streams. In addition, the biocompatible materials with excellent mechanical properties and low toxicity can also be used for tissue engineering, drug delivery and electrical energy storage devices.Inspec keywords: silver, filled polymers, polymer blends, nanocomposites, nanoparticles, nanofabrication, biodegradable materials, polymerisation, reduction (chemical), Fourier transform infrared spectra, transmission electron microscopy, X‐ray chemical analysis, X‐ray diffractionOther keywords: polyaniline‐chitosan‐silver‐nanobiocomposite, biodegradable polymers, biocompatibility, doping chemistry, nanotechnology, biodegradable PANI, polyaniline grafted chitosan copolymer, biodegradable materials, chemical in situ polymerisation, nanoparticle, polymer matrix, chemical reduction method, Fourier transform Infrared spectroscopy, transmission electron microscopy, energy dispersive X‐ray analysis, X‐ray diffraction, energy storage capacity, impedance properties, carcinogenic pollutants, toxic pollutants, photodegradation, toxic contaminants, natural water streams, waste waters, drug delivery, tissue engineering, electrical energy storage devices, mechanical properties, Ag  相似文献   

12.
Infection with human immunodeficiency virus (HIV)‐1 causes immunological disorders and death worldwide which needs to be further assisted by novel anti‐retroviral drug delivery systems. Consequently, finding newer anti‐retroviral pharmaceuticals by using biocompatible, biodegradable nanomaterials comprising a nanoparticle as core and a therapeutic agent is of high global interest. In this experiment, a second generation of a negatively charged nano‐biopolymer linear globular G2 dendrimer was carefully conjugated and loaded with well‐known anti‐HIV drugs lamivudine and efavirenz, respectively. They were characterised by a variety of analytical methods such as Zetasizer, Fourier‐transform infrared spectroscopy, elemental analysis and liquid chromatography‐mass spectroscopy. Additionally, conjugated lamivudine and loaded efazirenz with globular PEGylated G2 dendrimer were tested on an HEK293 T cell infected by single‐cycle replicable HIV‐1 virion and evaluated using XTT test and HIV‐1 P24 protein load. The results showed that lamivudine‐conjugated G2 significantly decreased retroviral activity without any cell toxicity. This effect was more or less observed by efavirenz‐loaded G2. These nano‐constructs are strongly suggested for further in vivo anti‐HIV assays.  相似文献   

13.
Green synthesis of organic Pt‐nanocomposite was accomplished using carboplatin as a precursor and novel biopolymer – gum kondagogu (GK) as a reducing agent. The synthesised GK stabilised organic Pt‐nanocomposite (GKCPt NC) was characterised by different analytical techniques such as ultraviolet–visible spectroscopy, nanoparticle analyser, scanning electron microscopy and energy dispersive X‐ray analysis, X‐ray diffraction (XRD), Fourier‐transform infrared spectroscopy, transmission electron microscopy (TEM), X‐ray photoelectron spectroscopy (XPS) and inductively coupled plasma optical emission spectrophotometer. The XRD pattern established the amorphous nature of GKCPt NC. TEM analysis revealed the homogeneous, monodisperse and spherical nature, with Pt metal size of 3.08 ± 0.62 nm. The binding energy at 71.2 and 74.6 eV show the presence of metallic platinum, Pt(0) confirmed by XPS studies. Further, in vitro radical scavenging and antitumour activity of GKCPt NC have been investigated. In comparison to GK and carboplatin, GKCPt NC showed superior 1, 1‐diphenyl‐2‐picrylhydrazyle activity of 87.82%, whereas 2, 2‐azinobis‐(3‐ethylbenzthinzoline‐6‐sulphonic acid) activity was 38.50%, respectively. In vitro studies of the antitumour property of GK, GKCPt NC and carboplatin were evaluated by potato disc tumour bioassay model. The efficacy of synthesised GKCPt NC concentration (IC50) on tumour inhibition was found to be 2.04‐fold lower as compared to carboplatin. Overall, the synthesised GKCPt NC shows both antitumour and antioxidant properties when compared to the original drug – carboplatin and might have promising applications in cancer therapy.Inspec keywords: nanoparticles, tumours, ultraviolet spectra, drugs, free radical reactions, X‐ray photoelectron spectra, platinum, nanocomposites, X‐ray diffraction, visible spectra, X‐ray chemical analysis, nanofabrication, transmission electron microscopy, scanning electron microscopy, cancer, polymer structure, filled polymers, Fourier transform infrared spectra, binding energy, drug delivery systems, nanomedicineOther keywords: antioxidant properties, green synthesis, ultraviolet–visible spectroscopy, energy dispersive X‐ray analysis, X‐ray diffraction, Fourier‐transform infrared spectroscopy, transmission electron microscopy, inductively coupled plasma optical emission spectrophotometry, antitumour activity, carboplatin precursor, biopolymer gum kondagogu stabilised organic Pt‐nanocomposite, reducing agent, different analytical techniques, scanning electron microscopy, X‐ray photoelectron spectroscopy, homogeneous particles, binding energy, in vitro radical scavenging, 1,1‐diphenyl‐2‐picrylhydrazyle activity, 2, 2‐azinobis‐(3‐ethylbenzthinzoline‐6‐sulphonic acid) activity, tumour inhibition, Pt  相似文献   

14.
Water‐soluble, stable nanoparticles of elemental sulphur with a size of 9‐52 nm have been synthesised using the stabilising potential of starch. Sulphide anions were used as sulphur precursors that were generated earlier from the bulk powder sulphur in the base‐reduction system NaOH‐N2H4·H2O followed by their oxidation with molecular oxygen to element sulphur atoms. Using a set of modern spectral and microscopic methods (XRD, optical spectroscopy, DLS, TEM), the phase state, elemental composition of the nanocomposites and their nanomorphological characteristics have been investigated. It was found that nanocomposites are formed as sulphur particles with the shape which is nearly spherical dispersed in the polysaccharide starch matrix with a pronounced tendency to cluster into ring formations. Water solubility and stability of the obtained nanoparticles is ensured by sorption of starch macromolecules on the surface of sulphur nanoparticles, with the thickness of the stabilising shell in a range of 10‐171 nm. In vitro experiments were carried out to study the anti‐microbial activity of the obtained sulphur nanocomposite (1.6% S) using the propidium iodide fluorescent dye staining method and the diffusion method. It showed that the water solution of the starch‐capped sulphur nanoparticles at the concentration of 6.25 µg/ml had a pronounced anti‐phytopathogenic activity against the potato ring rot pathogen Clavibacter michiganensis subsp. sepedonicus.  相似文献   

15.
The study explored biological synthesis of metallic silver nanoparticles (AgNPs) from the less explored non‐pathogenic coprophilous fungus, sterile mycelium, PM0651419 and evaluates the antimicrobial efficacy of biosynthesised AgNPs when impregnated in wound fabrics and in combination with six antimicrobial agents. AgNPs alone proved to be potent antibacterial agents and in combination they enhanced the antibacterial activity and spectrum of antibacterials used in the study against a microbiologically diverse battery of Gram positive, Gram negative and multidrug‐resistant bacteria. AgNPs impregnated on the wound dressings established their antibacterial activity by significantly reducing the bacterial load of pathogenic bacteria like Staphylococcus aureus and Bacillus subtilis e stablishing potential as effective antimicrobial wound dressings for treatment of polymicrobial wound infections. This study presents the first report on the potential of biosynthesis of AgNPs from the under explored class of coprophilous fungi. Their promise to be used in wound dressings and as potent antibacterials alone and in combination is evaluatedInspec keywords: silver, nanoparticles, nanofabrication, nanomedicine, biomedical materials, microorganisms, antibacterial activity, wounds, fabricsOther keywords: antibacterial activity, coprophilous fungus PM0651419, biological synthesis, metallic silver nanoparticles, nonpathogenic coprophilous fungus, sterile mycelium, antimicrobial efficacy, biosynthesised AgNPs, wound fabrics, microbiologically diverse battery, Gram positive bacteria, Gram negative bacteria, multidrug‐resistant bacteria, wound dressings, bacterial load, pathogenic bacteria, Staphylococcus aureus, Bacillus subtilis, polymicrobial wound infections, Ag  相似文献   

16.
This article analyses the effect of the size reduced Silver (Ag) loaded hydrogel by (a) lyophilisation (S1) (b) ball milling (S2) techniques and its effect on anti‐bacterial activity. The g loaded hydrogel, S1 and S2 shows an increase in swelling with an increase in pH. The swelling is more for Ag loaded hydrogel in low pH. For pH above 7, the swelling ratio of Ag loaded hydrogel and S1 are almost the same while S2 shows very less swelling. The anti‐bacterial studies reveal that S1 and Ag loaded hydrogel reacted well in S. aureus (Staphylococcus aureus) but no zone formation was seen in S2 .whereas no zone was formed in S1 and S2 for E‐coli (Escherichia coli). As the next step, the anti‐bacterial activity of Ag loaded hydrogel with the addition of curcumin (CS1―size reduced by lyophilisation, CS2―size reduced by ball milling) and turmeric (TS1―size reduced by lyophilisation, TS2―size reduced by ball milling) were investigated. In case of E.coli, a zonal formation of 1.2 cm for TS1 and 1.1 cm for TS2 and 1 cm for CS1 and 0.2 cm for CS2 was observed. For S.aureus, 1.1  and 1 cm were seen for TS1 and CS1. TS2 and CS2 did not show any zone formation. These studies clearly show that size reduction by lyophilisation (S1, TS1 and CS1) is more efficient in all the cases when compared to the ball milling technique (S2, TS2 and CS2). Comparing TS1 with S1 and CS1, TS1 has highly efficient/effective anti‐bacterial properties than S1 and CS1. Therefore, lyophilised hydrogel incorporating turmeric and silver (TS1) is an excellent choice compared to using curcumin for wound dressing applications.  相似文献   

17.
Diabetes mellitus has been considered as a heterogeneous metabolic disorder characterised by complete or relative impairment in the production of insulin by pancreatic β‐cells or insulin resistance. In the present study, propanoic acid, an active biocomponent isolated from Cassia auriculata is employed for the synthesis of propanoic acid functionalised gold nanoparticles (Pa@AuNPs) and its anti‐diabetic activity has been demonstrated in vitro. In vitro cytotoxicity of synthesised Pa@AuNPs was performed in L6 myotubes. The mode of action of Pa@AuNPs exhibiting anti‐diabetic potential was validated by glucose uptake assay in the presence of Genistein (insulin receptor tyrosine kinase inhibitor) and Wortmannin (Phosphatidyl inositide kinase inhibitor). Pa@AuNPs exhibited significant glucose uptake in L6 myotubes with maximum uptake at 50 ng/ml. Assays were performed to study the potential of Pa@AuNPs in the inhibition of protein‐tyrosine phosphatase 1B, α‐glucosidases, and α‐amylase activity.Inspec keywords: molecular biophysics, biomedical materials, sugar, enzymes, nanofabrication, gold, patient treatment, organic‐inorganic hybrid materials, biochemistry, diseases, cellular biophysics, nanoparticles, toxicology, nanomedicineOther keywords: glucose uptake assay, α‐amylase activity, organic–inorganic hybrid gold nanoparticles, diabetes mellitus, heterogeneous metabolic disorder, pancreatic β‐cells, insulin resistance, propanoic acid, antidiabetic potential, antidiabetic activity, in vitro cytotoxicity, L6 myotubes, Genistein, IRTK inhibitor, Wortmannin, P13K inhibitor, protein‐tyrosine phosphatase 1B, α‐glucosidases, Cassia auriculata, Au  相似文献   

18.
In the present study, water‐soluble hybrid selenium‐containing nanocomposites have been synthesised via soft oxidation of selenide‐anions, preliminarily generated from elemental bulk‐selenium in the base‐reduction system ‘N2 H4 –NaOH’. The nanocomposites obtained consist of Se0 NPs (4.6–24.5 nm) stabilised by κ‐carrageenan biocompatible polysaccharide. The structure of these composite nanomaterials has been proven using complementary physical–chemical methods: X‐ray diffraction analysis, transmission electron microscopy, optical spectroscopy, and dynamic light scattering. Optical ranges of ‘emission/excitation’ of aqueous solutions of nanocomposites with Se0 NPs of different sizes are established and the most important parameters of their luminescence are determined. For the obtained nanocomposites, the expressed antiradical activity against free radicals 2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid has been found, the value of which depends on the size of selenium nanoparticles. It is experimentally revealed that all obtained nanocomposites are low toxic (LD50 >2000 mg/kg). It is also found that small selenium nanoparticles (6.8 nm), in contrast to larger nanoparticles (24.5 nm), are accumulated in organisms to significantly increase the level of selenium in the liver, kidneys, and brain (in lesser amounts) of rats.Inspec keywords: nanobiotechnology, free radical reactions, oxidation, enzymes, selenium, solubility, nanofabrication, transmission electron microscopy, X‐ray diffraction, free radicals, reduction (chemical), biomedical materials, nanoparticles, nanomedicine, light scattering, organic‐inorganic hybrid materials, biochemistry, nanocompositesOther keywords: κ‐carrageenan biocompatible polysaccharide, composite nanomaterials, complementary physical–chemical methods, X‐ray diffraction analysis, transmission electron microscopy, optical spectroscopy, dynamic light scattering, optical ranges, expressed antiradical activity, 2,2‐diphenyl‐1‐picrylhydrazyl, 3‐ethylbenzothiazoline‐6‐sulphonic acid, comparative assessment, toxicity, κ‐carrageenan‐capped selenium nanoparticles, water‐soluble hybrid selenium‐containing nanocomposites, soft oxidation, selenide‐anions, elemental bulk‐selenium, base‐reduction system, free radicals, 2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid, selenium nanoparticles, nanocomposites, liver, kidneys, brain, luminescence, size 4.6 nm to 24.5 nm  相似文献   

19.
In the present work, the preparation, characterisation, and efficiency of two different silica nanostructures as release vehicles of Cisplatin are reported. The 1‐hexadeciltrimethyl‐ammonium bromide templating agent was used to obtain mesoporous silica nanoparticles which were later loaded with Cisplatin. While sol–gel silica was very fast prepared using an excess of acetic acid during the hydrolysis–condensation reactions of tetraethylorthosilicate and at the same time the Cisplatin was added. Several physicochemical techniques including spectroscopies, electronic microscopy, X‐ray diffraction, N2 adsorption–desorption were used to characterise the silica nanostructures. An in vitro Cisplatin release test was carried out using artificial cerebrospinal fluid. Finally, the toxicity of all silica nanostructures was tested using the C6 cancer cell line. The spectroscopic results showed the suitable stabilisation of Cisplatin into the two different silica nanostructures. A large surface area was obtained for the mesoporous silica nanoparticles, while low areas were obtained in the silica nanoparticles. Cisplatin was released faster from mesoporous silica channels than from inside of aggregates nanoparticles silica. Cisplatin alone, as well as, cisplatin released from both silica nanostructures exerted a toxic effect on cancer cells. In contrast, both silica structures without the drug did not exert any toxic effect.Inspec keywords: cellular biophysics, desorption, adsorption, biomedical materials, sol‐gel processing, silicon compounds, cancer, toxicology, nanofabrication, brain, condensation, mesoporous materials, nanoparticles, X‐ray diffraction, nanomedicine, drugs, aggregates (materials)Other keywords: mesoporous silica channels, silica‐based nanoparticles, cancer brain cells, silica nanostructures, 1‐hexadeciltrimethyl‐ammonium bromide, mesoporous silica nanoparticles, sol‐gel silica, C6 cancer cell line, in vitro cisplatin release test, C6 cancer cell line, acetic acid, hydrolysis‐condensation reactions, tetraethylorthosilicate, physicochemical techniques, electronic microscopy, X‐ray diffraction, N2 adsorption‐desorption, artificial cerebrospinal fluid, toxicity, toxic effect, N2 , SiO2   相似文献   

20.
A simple ultrasonic assisted chemical technique was used to synthesise cadmium oxide (CdO) nanoparticles (NPs) and CdO NPs/c‐Multiwalled carbon nanotube (c‐MWCNT) nanocomposite fibres.To confirm the physio‐chemico properties and to analyse surface morphology of the obtained nanomaterials X‐Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM) were performed. To evaluate the anti‐cancer property of CdO NPs, c‐MWCNT NPs and CdO NPs/c‐MWCNT nanocomposite fibres, an anti‐proliferative assay test (Methylthiazolyl diphenyl‐ tetrazolium bromide ‐ MTT assay) were performed on HeLa cells which further estimated IC50 value (Least concentration of sample in which nearly 50% of cells remain alive) under in‐vitro conditions. On comparison, CdONPs/c‐MWCNT based system was found to be superior by achieving 52.3% cell viability with its minimal IC50 value of 31.2 μg/ml. Lastly, the CdO NPs based system was taken up for an apoptotic study using DNA fragmentation assay for estimating its ability to cleave the DNA of the HeLa cells into internucleosomal fragments using the agarose gel electrophoresis method. In conclusion, based on our observations, CdO NPs/c‐MWCNT hybrid based system can be further used for the development of efficient drug delivery and therapeutic systems.Inspec keywords: drug delivery systems, electrophoresis, oxidation, toxicology, DNA, nanoparticles, drugs, field emission electron microscopy, scanning electron microscopy, nanofabrication, surface morphology, cancer, X‐ray diffraction, nanomedicine, cellular biophysics, filled polymers, biomedical materials, molecular biophysics, biochemistry, Fourier transform infrared spectra, multi‐wall carbon nanotubesOther keywords: c‐MWCNT nanoparticles, apoptotic study, HeLa cancer cell line, cadmium oxide nanoparticles, c‐MWCNT NPs, anti‐proliferative assay test [methyl thiazolyl diphenyl‐tetrazolium bromide assay], human epithelioid cervix carcinoma cells, live cells, CdO NP‐based system, IC50 concentration, HeLa cell line, cell deaths, CdO‐C  相似文献   

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