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1.
Waste Manag Res ; : 734242X20904403, 2020 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-32077381

RESUMO

The present work is focused on pyrolysis of polystyrene waste for production of combustible hydrocarbons. The experiments were performed in an indigenously made furnace in the presence of a laboratory synthesised copper oxide. The pyrolysis products were collected and characterised. The Fourier transform infrared spectra showed that the liquid fraction contains C-H, C-O, C-C, C=C and O-H bonds, which correspond to various aliphatic and aromatic compounds. Gas chromatography-mass spectrometry traced compounds ranging from C1 to C4 in the gaseous fraction, whereas in the liquid fraction 15 components ranging from C3 to C24 were detected. From the results it has been concluded that CuO as a catalyst not only increased the liquid yield but also reduced the degradation temperature to great extent. Fuel properties of the pyrolysis oil were determined and compared with standard values of commercial fuel oil. The comparison suggested potential application of pyrolysis oil for domestic and commercial use.

2.
Spectrochim Acta A Mol Biomol Spectrosc ; 229: 118002, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31923785

RESUMO

Maltol capped silver nanoparticles (McAgNPs) were synthesized using maltol (3-hydroxy-2-methyl-4-pyrone) as reducing and capping agent. McAgNPs were characterized by Visible and FTIR (Fourier transform infrared) spectroscopy, dynamic light scattering (DLS), and atomic force microscopy (AFM). Bright yellow color McAgNPs showed surface plasmon resonance (SPR) band at 436 nm, spherical shape and the average size between 35 to 50 nm. McAgNPs revealed higher stability against varying storage time, temperature, pH and salt concentrations. McAgNPs were successfully utilized for the selective and highly sensitive colorimetric detection of cysteine (Cys). Addition of Cys in a solution of McAgNPs, resulted a rapid change in color from yellow to orange because of the formation of nanoaggregates as confirmed by Visible/FTIR spectroscopy, DLS, and AFM studies. The estimated limit of detection (0.043 µM) was found to be more sensitive than previously reported other optical methods. The practical applicability of probe was also established by spiking the known concentrations of Cys in biological (blood plasma and urine) and environmental (tap and lake water) samples with significant recovery rates (92-104.6%). Despite being nontoxic to various tested cell lines, McAgNPs demonstrated potent antimicrobial, antibiofilm, and biofilm eradicating activities, thus potentially valuable in diagnostics and/or the synthesis of other nanocomposite material for broader applications.

3.
Waste Manag Res ; 38(2): 202-212, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31405341

RESUMO

Due to a huge increase in polymer production, a tremendous increase in municipal solid waste is observed. Every year the existing landfills for disposal of waste polymers decrease and the effective recycling techniques for waste polymers are getting more and more important. In this work pyrolysis of waste polystyrene was performed in the presence of a laboratory synthesized copper oxide. The samples were pyrolyzed at different heating rates that is, 5°Cmin-1, 10°Cmin-1, 15°Cmin-1 and 20°Cmin-1 in a thermogravimetric analyzer in inert atmosphere using nitrogen. Thermogravimetric data were interpreted using various model fitting (Coats-Redfern) and model free methods (Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman). Thermodynamic parameters for the reaction were also determined. The activation energy calculated applying Coats-Redfern, Ozawa-Flynn-Wall, Kissinger-Akahira-Sunose and Friedman models were found in the ranges 105-148.48 kJmol-1, 99.41-140.52 kJmol-1, 103.67-149.15 kJmol-1 and 99.93-141.25 kJmol-1, respectively. The lowest activation energy for polystyrene degradation in the presence of copper oxide indicates the suitability of catalyst for the decomposition reaction to take place at lower temperature. Moreover, the obtained kinetics and thermodynamic parameters would be very helpful in determining the reaction mechanism of the solid waste in a real system.


Assuntos
Poliestirenos , Resíduos Sólidos , Calefação , Cinética , Termogravimetria
4.
Colloids Surf B Biointerfaces ; 186: 110676, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31838269

RESUMO

Amphiphilic calixarenes are preferred to generate nano-cargos for drugs due to their stability, possibilities for modification and intrinsic host cavities. Here we are reporting the synthesis of amphiphilic calixarene and its evaluation as drug delivery system. Water soluble amphiphilic p-sulfonatocalix[6]arene was synthesized through sulfonation and lipophilic conjugation on its upper and lower rims respectively. The synthesized amphiphile self-assembled into nanostructures in the presence of Clarithromycin and FITC as model hydrophobic drugs followed by a wide range of characterization. Clarithromycin loaded self-assembled nanostructures was screened for its bactericidal potential in resistant S. pneumonia through various in-vitro assays. The amphiphilic calixarene self-assembled into polydispersed nanostructures with 136.45 ±â€¯2.41 nm mean diameter and -49.93 ±â€¯0.35 mV surface charges. The amphiphile was capable to load Clarithromycin (57.54 ±â€¯1.88 %) and fluorescent dye and was highly stable. Clarithromycin loaded nanostructures revealed significant biofilm and bacterial growth inhibition and cell destruction properties. Results authenticate calixarene amphiphile as an efficient nano-carrier for improving Clarithromycin efficacy.

5.
Nanomaterials (Basel) ; 9(11)2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31726731

RESUMO

We report a novel, simple, efficient, and green protocol for biogenic synthesis of silver nanoparticles (AgNPs) in aqueous solution using clove (Syzygium aromaticum) extract as a reducing and protecting agent. Ultraviolet-visible (UV-Vis) spectroscopy was employed to monitor the localized surface plasmon resonance (LSPR) band of clove extract-derived AgNPs prepared under various conditions. Fourier-transform infrared (FTIR) spectroscopy analysis provided information about the surface interaction of the clove extract with the AgNPs. Ultrahigh-resolution transmission electron microscopy (UHRTEM) results confirmed the formation of spherical, uniformly distributed clove extract-capped AgNPs with sizes in the range of 2-20 nm (average size: 14.4 ± 2 nm). Powder X-ray diffractometry analysis (PXRD) illustrated the formation of pure crystalline AgNPs. These AgNPs were tested as a colorimetric sensor to detect trace amounts of vinclozolin (VIN) by UV-Vis spectroscopy for the first time. The AgNP-based sensor demonstrated very sensitive and selective colorimetric detection of VIN, in the range of 2-16 µM (R2 = 0.997). The developed sensor was green, simple, sensitive, selective, economical, and novel, and could detect trace amounts of VIN with limit of detection (LOD) = 21 nM. Importantly, the sensor was successfully employed for the determination of VIN in real water samples collected from various areas in Turkey.

6.
Pak J Pharm Sci ; 32(4): 1615-1619, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31608881

RESUMO

The present study investigates the pharmaceutically bioactive compounds in Methanol, n-hexane and ethyl acetate extracted samples from the root of Periploca hydaspidis through Gas Chromatography and Mass Spectroscopy analysis. The mass spectrum obtained was compared with the data base of National Institute of Standards and Technology (NIST) which contains more than 62000 patterns of the mass spectrum. During matching with NIST library the match factor greater than 700 was considered only for better and pure results. The GC-MS analysis revealed the presence of various important compounds in the extracts like Lupeol, Furanol, Decanal, Decanoic acid, Dioxane and Oxirane. Besides these compounds the analysis also revealed the presence of antibiotics, fatty acids and protein.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas/métodos , Periploca/química , Compostos Fitoquímicos/análise , Extratos Vegetais/química , Raízes de Plantas/química , Plantas Medicinais/química , Solventes/química
7.
ACS Omega ; 4(16): 16860-16866, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31646232

RESUMO

The glassy carbon electrode was fabricated with multifunctional bis-triazole-appended calix[4]arene and then used for the simultaneous detection of Zn(II), Pb(II), As(III), and Hg(II). Before applying the square-wave anodic stripping voltammetry, the sensitivity and precision of the modified electrode was assured by optimizing various conditions such as the modifier concentration, pH of the solution, deposition potential, accumulation time, and supporting electrolytes. The modified glassy carbon electrode was found to be responsive up to picomolar limits for the aforementioned heavy metal ions, which is a concentration limit much lower than the threshold level permitted by the World Health Organization. Importantly, the designed sensing platform showed anti-interference ability, good stability, repeatability, reproducibility, and applicability for the detection of multiple metal ions. The detection limits obtained for Zn(II), Pb(II), As(III), and Hg(II) are 66.3, 14.6, 71.9, and 28.9 pM, respectively.

8.
Med Chem ; 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31544702

RESUMO

BACKGROUND: Acanthamoeba is an opportunistic pathogen widely spread in the environment. Acanthamoeba causes excruciating keratitis which can lead to blindness. The lack of effective drugs and its ability to form highly resistant cyst are one of the foremost limitations against successful prognosis. Current treatment involves mixture of drugs at high doses but still recurrence of infection can occur due to ineffectiveness of drugs against the cyst form. Pyridine and its natural and synthetic derivatives are potential chemotherapeutic agents due to their diverse biological activities. OBJECTIVE: To study the antiamoebic effects of four novel synthetic dihydropyridine (DHP) compounds against Acanthamoeba castellanii belonging to the T4 genotype. Furthermore, to evaluate their activity against amoeba-mediated host cells cytopathogenicity as well as their cytotoxicity against human cells. METHOD: Dihydropyridines were synthesized by cyclic dimerization of alkylidene malononitrile derivatives. Four analogues of functionally diverse DHPs were tested against Acanthamoeba castellanii by using amoebicidal, encystation and excystation assays. Moreover, Lactate dehydrogenase assays were carried out to study cytopathogenicity and cytotoxicity against human cells. RESULTS: These compounds showed significant amoebicidal and cysticidal effects at 50 µM concentration, whereas, two of the DHP derivatives also significantly reduced Acanthamoeba-mediated host cell cytotoxicity. Moreover, these DHPs were found to have low cytotoxicity against human cells suggesting a good safety profile, and they can be employed as therapeutic agents. CONCLUSION: The results suggest that DHPs have potential against Acanthamoeba especially against the more resistant cyst stage and can be assessed further for drug development.

9.
Mater Sci Eng C Mater Biol Appl ; 105: 110111, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31546392

RESUMO

Multiple drug resistant (MDR) has become a major issue in developing countries. MDR bacterial infections lead to significant increase in morbidity, mortality and cost of prolonged treatments. Therefore, designing of strategies for improving the antimicrobial potential of the therapeutic agents are highly required. Metal organic frameworks (MOFs) are highly tunable hybrid material, consist of metal ions linked together by organic bridging ligands have been used as an efficient drug delivery carrier because of their biodegradability, low toxicity and structure integrity upon loading and functionalizing process. Current study was based on the synthesis of chitosan coated MOFs with enhanced contact with S. aureus cell surface. Chitosan is deacetylated derivative of chitin and capable for non-bonding interaction with negatively charged bacterial cell leading to enhanced contact of MOFs with S. aureus. Chitosan coated MOFs were characterized with various techniques such as atomic force microscopy, scanning electron microscopy, DLS, FT-IR, TGA, DSC and Powder X-ray diffraction. They were also studied for their efficacy on resistant S. aureus, results revealed that Vancomycin bactericidal activity significantly increased upon loading in chitosan coated MOFs and caused increased inhibition of resistant S. aureus. AFM analysis of S. aureus strains clearly revealed complete distortion of morphology by treating with chitosan modified drug loaded MOFs. Findings of the current study suggest the potential of chitosan coated MOFs for reversing bacterial resistance against Vancomycin and provide new perspectives for improved antibiotic therapy of infections associated with MDR.


Assuntos
Antibacterianos/farmacologia , Quitosana/síntese química , Materiais Revestidos Biocompatíveis/síntese química , Farmacorresistência Bacteriana/efeitos dos fármacos , Estruturas Metalorgânicas/síntese química , Staphylococcus aureus/efeitos dos fármacos , Vancomicina/farmacologia , Varredura Diferencial de Calorimetria , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Porosidade , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Propriedades de Superfície , Termogravimetria , Difração de Raios X
10.
Pak J Pharm Sci ; 32(3): 1069-1080, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31278722

RESUMO

This research investigates the synthesis and characterization of gold nanoparticles from Periploca hydaspidis and their antimicrobial and anti oxidant activity. The synthesis of AuNPs was confirmed by UV-Vis spectrophotometer and structure by a high resolution atomic force microscope. X-ray diffraction and Fourier transformed infrared spectroscopy was used to study the crystallite size and different functional groups. DPPH radical scavenging activity and disc diffusion protocol was applied for the determination of antioxidant and antimicrobial activity. A ratio of 1:8 of 1mM AuCl3 solutions with plant boiled extract used for synthesis of gold nano-particles. The formation of the gold nano-particles was determined by the color change from yellow to dark purple which were confirmed by UV-Vis spectrophotometer. Gold nano-particles were stable between 24°C and 39°C, mM concentration of the salt and neutral pH. The groups responsible for the synthesis of gold nano-paricles were Alkenes and aliphatic amines. The AuNP were cubic in nature and the nanocrystallite size was 6.99nm. Gold nano-particles revealed good antioxidant activity and controlled the growth of K. pnemoniae, E. coli, X. compestris, C. albicans and P. chrysogenum.


Assuntos
Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Nanopartículas Metálicas/química , Periploca/química , Anti-Infecciosos/síntese química , Antioxidantes/síntese química , Candida albicans/efeitos dos fármacos , Avaliação Pré-Clínica de Medicamentos , Estabilidade de Medicamentos , Escherichia coli/efeitos dos fármacos , Ouro/química , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Tamanho da Partícula , Extratos Vegetais/química , Plantas Medicinais/química , Espectrofotometria Ultravioleta , Difração de Raios X , Xanthomonas campestris/efeitos dos fármacos
11.
J Liposome Res ; : 1-8, 2019 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-31185766

RESUMO

Nonionic surfactants have an extraordinary fascination for the researchers in the field of drug delivery for enhancing drug bioavailability and therapeutic efficacy. Here, we are reporting the synthesis, characterization, drug entrapment efficiency (EE), critical micellar concentration, and biocompatibility evaluation of sulphanilamide based new nonionic surfactants. The surfactants were synthesized in single step reactions and characterized through 1H NMR, FT-IR, and mass spectrometric analysis. The surfactants abilities for niosomal vesicles formation were investigated utilizing Ciprofloxacin as a model drug. The drug loaded niosomal suspension of the synthesized surfactants was screened for shape; size, polydispersity index, and drug EE utilizing AFM, Zetasizer, and UV, respectively. The compatibility of the drug in drug loaded vesicles with excipients was assessed utilizing FT-IR spectroscopy. The biocompatibility of the synthesized surfactants was assessed through blood haemolysis and cell cytotoxicity assays. Results of this study showed that the synthesized surfactants were quite haemocompatible and nontoxic in nature and were able to form spherical vesicles. The size and drug EE of the vesicles were dependant on the length of surfactant aliphatic chain. Surfactant with long aliphatic chain was more efficient in entrapping the drug and could be used as a potential vesicular drug delivery vehicle for improving the lipophilic drug's bioavailability.

12.
Int. microbiol ; 22(2): 239-246, jun. 2019. ilus, graf, tab
Artigo em Inglês | IBECS | ID: ibc-184830

RESUMO

Silver nanoparticles (SN) have been recently developed as a new class of antimicrobial agents against numerous pathogenic microorganisms. SN have also been used as efficient drug delivery systems and have been linked with increasing drug potency. Here, we demonstrated the enhanced antifungal efficacy of nystatin (NYT) and fluconazole (FLU) after conjugation with SN. The antifungal bioactivity of NYT- and FLU-coated SN was evaluated against Candida albicans ATCC 10231 and Aspergillus brasiliensis ATCC 16404 by the agar tube dilution method. The aim of this study was to determine and compare the antifungal efficacy of NYT and FLU with their SN and, finally, the combination of both nanoparticles as NYT-SN + FLU-SN against pathogenic fungi. The results indicated that all test samples showed a dose-dependent response against tested fungi. SN significantly enhanced the antifungal effects of NYT and FLU as compared to drugs alone. We observed a remarkable increase in the percent inhibition of both fungi (90-100%) when treated with a combination of both nanoparticles NYT-SN + FLU-SN at 200 μg/mL only. Furthermore, the morphological modifications occurred at the surface of fungal species were also analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). While tested against primary human cell line, all SN showed negligible cytotoxicity. Hence, these results suggest that the combination of SN with NYT and FLU may have clinical implications in the treatment of fungal infections. However, in vivo studies are needed before recommending the use of these nanoparticles safely in clinical situations


No disponible


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Nanopartículas Metálicas , Prata/farmacologia , Fluconazol/farmacologia , Nistatina/farmacologia , Aspergillus/ultraestrutura , Candida albicans/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Propriedades de Superfície/efeitos dos fármacos
13.
Parasitol Res ; 118(7): 2295-2304, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31093751

RESUMO

Acanthamoeba castellanii belonging to the T4 genotype is an opportunistic pathogen which is associated with blinding eye keratitis and rare but fatal central nervous system infection. A. castellanii pose serious challenges in antimicrobial chemotherapy due to its ability to convert into resistant, hardy shell-protected cyst form that leads to infection recurrence. The fatty acid composition of A. castellanii trophozoites is known to be most abundant in oleic acid which chemically is an unsaturated cis-9-Octadecanoic acid and naturally found in animal and vegetable fats and oils. This study was designed to evaluate antiacanthamoebic effects of oleic acid against trophozoites, cysts as well as parasite-mediated host cell cytotoxicity. Moreover, oleic acid-conjugated silver nanoparticles (AgNPs) were also synthesized and tested against A. castellanii. Oleic acid-AgNPs were synthesized by chemical reduction method and characterized by ultraviolet-visible spectrophotometry, atomic force microscopy, dynamic light scattering analysis, and Fourier transform infrared spectroscopy. Viability, growth inhibition, encystation, and excystation assays were performed with 10 and 5 µM concentration of oleic acid alone and oleic acid-conjugated AgNPs. Bioassays revealed that oleic acid alone and oleic acid-conjugated AgNPs exhibited significant antiamoebic properties, whereas nanoparticle conjugation further enhanced the efficacy of oleic acid. Phenotype differentiation assays also showed significant inhibition of encystation and excystation at 5 µM. Furthermore, oleic acid and oleic acid-conjugated AgNPs also inhibited amoebae-mediated host cell cytotoxicity as determined by lactate dehydrogenase release. These findings for the first time suggest that oleic acid-conjugated AgNPs exhibit antiacanthamoebic activity that hold potential for therapeutic applications against A. castellanii.


Assuntos
Ceratite por Acanthamoeba/tratamento farmacológico , Acanthamoeba castellanii/efeitos dos fármacos , Amebicidas/farmacologia , Nanopartículas Metálicas/química , Ácido Oleico/farmacologia , Ceratite por Acanthamoeba/parasitologia , Amebicidas/química , Animais , Olho/parasitologia , Humanos , Microscopia de Força Atômica , Ácido Oleico/química , Prata/química , Espectrofotometria Ultravioleta , Trofozoítos/efeitos dos fármacos
14.
ACS Chem Neurosci ; 10(6): 2692-2696, 2019 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-30970208

RESUMO

Primary amoebic meningoencephalitis (PAM), a deadly brain infection, is caused by brain-eating amoeba Naegleria fowleri. The current first line of treatment against PAM is a mixture of amphotericin B, rifampin, and miltefosine. Since, no single effective drug has been developed so far, the mortality rate is above 95%. Moreover, severe adverse side effects are associated with these drugs. Nanotechnology has provided several advances in biomedical applications especially in drug delivery and diagnosis. Herein, for the first time we report antiamoebic properties of cinnamic acid (CA) and gold nanoparticles conjugated with CA (CA-AuNPs) against N. fowleri. CA-AuNPs were successfully synthesized by sodium borohydride reduction of tetrachloroauric acid. Size and morphology were determined by atomic force microscopy (AFM) while the surface plasmon resonance band was analyzed by ultraviolet-visible (UV-vis) spectrophotometry for the characterization of the nanoparticles. Amoebicidal and cytopathogenicity (host cell cytotoxicity) assays revealed that both CA and CA-AuNPs displayed significant anti- N. fowleri properties ( P < 0.05), whereas nanoparticles conjugation further enhanced the anti- N. fowleri effects of CA. This study established a potential drug lead, while CA-AuNPs appear to be promising candidate for drug discovery against PAM.

15.
Sci Rep ; 9(1): 3122, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30816269

RESUMO

Herein, we report green synthesized nanoparticles based on stabilization by plant gums, loaded with citrus fruits flavonoids Hesperidin (HDN) and Naringin (NRG) as novel antimicrobial agents against brain-eating amoebae and multi-drug resistant bacteria. Nanoparticles were thoroughly characterized by using zetasizer, zeta potential, atomic force microscopy, ultravoilet-visible and Fourier transform-infrared spectroscopic techniques. The size of these spherical nanoparticles was found to be in the range of 100-225 nm. The antiamoebic effects of these green synthesized Silver and Gold nanoparticles loaded with HDN and NRG were tested against Acanthamoeba castellanii and Naegleria fowleri, while antibacterial effects were evaluated against methicillin-resistant Staphylococcus aureus (MRSA) and neuropathogenic Escherichia coli K1. Amoebicidal assays revealed that HDN loaded Silver nanoparticles stabilized by gum acacia (GA-AgNPs-HDN) quantitatively abolished amoeba viability by 100%, while NRG loaded Gold nanoparticles stabilized by gum tragacanth (GT-AuNPs-NRG) significantly reduced the viability of A. castellanii and N. fowleri at 50 µg per mL. Furthermore, these nanoparticles inhibited the encystation and excystation by more than 85%, as well as GA-AgNPs-HDN only completely obliterated amoeba-mediated host cells cytopathogenicity. Whereas, GA-AgNPs-HDN exhibited significant bactericidal effects against MRSA and E. coli K1 and reduced bacterial-mediated host cells cytotoxicity. Notably, when tested against human cells, these nanoparticles showed minimal (23%) cytotoxicity at even higher concentration of 100 µg per mL as compared to 50 µg per mL used for antimicrobial assays. Hence, these novel nanoparticles formulations hold potential as therapeutic agents against infections caused by brain-eating amoebae, as well as multi-drug resistant bacteria, and recommend a step forward in drug development.

16.
Int Microbiol ; 22(2): 239-246, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30810990

RESUMO

Silver nanoparticles (SN) have been recently developed as a new class of antimicrobial agents against numerous pathogenic microorganisms. SN have also been used as efficient drug delivery systems and have been linked with increasing drug potency. Here, we demonstrated the enhanced antifungal efficacy of nystatin (NYT) and fluconazole (FLU) after conjugation with SN. The antifungal bioactivity of NYT- and FLU-coated SN was evaluated against Candida albicans ATCC 10231 and Aspergillus brasiliensis ATCC 16404 by the agar tube dilution method. The aim of this study was to determine and compare the antifungal efficacy of NYT and FLU with their SN and, finally, the combination of both nanoparticles as NYT-SN + FLU-SN against pathogenic fungi. The results indicated that all test samples showed a dose-dependent response against tested fungi. SN significantly enhanced the antifungal effects of NYT and FLU as compared to drugs alone. We observed a remarkable increase in the percent inhibition of both fungi (90-100%) when treated with a combination of both nanoparticles NYT-SN + FLU-SN at 200 µg/mL only. Furthermore, the morphological modifications occurred at the surface of fungal species were also analyzed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). While tested against primary human cell line, all SN showed negligible cytotoxicity. Hence, these results suggest that the combination of SN with NYT and FLU may have clinical implications in the treatment of fungal infections. However, in vivo studies are needed before recommending the use of these nanoparticles safely in clinical situations.


Assuntos
Antifúngicos/farmacologia , Aspergillus/efeitos dos fármacos , Candida albicans/efeitos dos fármacos , Sinergismo Farmacológico , Fluconazol/farmacologia , Nanopartículas Metálicas , Nistatina/farmacologia , Prata/farmacologia , Aspergillus/ultraestrutura , Candida albicans/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Propriedades de Superfície/efeitos dos fármacos
17.
Biomed Pharmacother ; 112: 108624, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30784921

RESUMO

Rheumatoid arthritis (RA) is a chronic autoimmune disease of synovial inflammation and joint destruction. This study reports anti-arthritic potential of opuntioside-I opuntiol, and its gold and silver nanoparticles (NPs) against Complete Freund's Adjuvant (CFA)-induced arthritic rats. The mechanistic studies were performed targeting TLRs (TLR-2 and TLR-4) and cytokines (IL-1ß and TNF-α) expressions to validate their anti-inflammatory and immuno-modulatory response. The nano-formulations were successfully characterized employing Atomic Force Microscopy (AFM) and Dynamic Light Scattering (DLS) analysis. Opuntiol and opuntioside (OP and OPG: 10, 50 and 100 mg/kg) and opuntiol-coated silver and gold NPs (OP-AgNPs and OP-AuNPs: 0.5, 1 and 3 mg/kg) treatments in arthritic rat have shown minimal arthritic score exhibiting mild to moderate articular changes and tissue swelling in ankle joints. Radiographic examination reveals significant reduction in synovitis with improvement in joints degenarative changes in the presence of aforementioned treatments. Likewise, histology of rat ankle joints depicted comparatively lesser influx of inflammatory cells and diminished granulamatous inflammation. Moreover, treatment groups suppressed protein and mRNA expressions of TLRs (TLR-2 and TLR-4) and cytokines (IL-1ß and TNF-α) levels were also significantly declined in the presence of OPG, OP and its NPs comparing to arthritic control. This investigation concludes, the tested compounds and nano-formulations successfully restored the disease progression in CFA-induced arthritic rat owing to their immunomodulatory and anti-inflammatory potentials and can be considered for RA targeted therapy to address the utmost challenges of the disease.


Assuntos
Antirreumáticos/uso terapêutico , Artrite Experimental/tratamento farmacológico , Ácidos Cumáricos/uso terapêutico , Nanopartículas Metálicas/uso terapêutico , Monossacarídeos/uso terapêutico , Receptor 2 Toll-Like/antagonistas & inibidores , Receptor 4 Toll-Like/antagonistas & inibidores , Animais , Antirreumáticos/administração & dosagem , Antirreumáticos/química , Artrite Experimental/imunologia , Artrite Experimental/metabolismo , Ácidos Cumáricos/administração & dosagem , Ácidos Cumáricos/química , Feminino , Adjuvante de Freund , Ouro/química , Nanopartículas Metálicas/administração & dosagem , Nanopartículas Metálicas/química , Monossacarídeos/administração & dosagem , Monossacarídeos/química , Ratos Wistar , Prata/química
18.
Nanomaterials (Basel) ; 9(1)2019 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-30634575

RESUMO

This study involves environmentally friendly synthesis of copper nanoparticles in aqueous medium without inert gas protection, using ranolazine as a capping material. UV-Visible (UV-Vis) spectrometry showed that ranolazine-derived copper nanoparticles (Rano-Cu NPs) demonstrate a localized surface plasmon resonance (LSPR) band at 573 nm with brick-red color under optimized parameters, including pH, reaction time, and concentrations of copper salt, hydrazine hydrate, and ranolazine. The coating of ranolazine on the surface of Cu NPs was studied via Fourier transform infrared (FTIR) spectroscopy. Scanning electron microscopy (SEM) revealed that Rano-Cu NPs consist of spherical particles. X-ray diffraction (XRD) verified that Rano-Cu NPs are crystalline in nature. Atomic force microscopy (AFM) showed that the average size of Rano-Cu NPs was 40 ± 2 nm in the range of 22⁻95 nm. Rano-Cu NPs proved to be highly sensitive as a selective colorimetric sensor for As3+ via color change from brick red to dark green, in the linear range of 3.0 × 10-7 to 8.3 × 10-6 M, with an R² value of 0.9979. The developed sensor is simple, cost effective, highly sensitive, and extremely selective for As3+ detection, showing a low detection limit (LDL) of 1.6 × 10-8 M. The developed sensor was effectively tested for detection of As3+ in some water samples.

19.
Drug Dev Ind Pharm ; 45(5): 703-714, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30557053

RESUMO

Emergence of multidrug resistance (MDR) has limited the success of chemotherapeutic agents. Reversal of drugs efflux systems through combination therapy has got wider attention for increasing anticancer drugs efficacy. This study aims at co-encapsulation of Paclitaxel with Naringin in mixed polymeric micelles for enhanced anticancer activity of the drug. Drug-loaded micelles were prepared using two different amphiphilic block co-polymers and were characterized for morphology, size, zeta potential, drug encapsulation, in vitro release and stability using atomic force microscope (AFM), zetasizer, UV spectrophotometer, and FT-IR. MTT assay and fluorescence microscopy were used for in vitro cytotoxicity and cellular uptake studies. Nano-size micelles with spherical morphology and negative charge encapsulated 76.52 ± 0.94% and 32.87 0.61% Paclitaxel and Naringin, respectively. The micelles were thermally stable and retained 87.05 ± 0.69% and 92.88 ± 2.17% Paclitaxel and Naringin upon one-month storage. Maximum drug release was achieved at fourth hour of the study for both the loaded drugs. Paclitaxel co-encapsulation with Naringin synergistically improved its intracellular uptake and 65% in vitro cytotoxicity against breast cancer cells was achieved at its lower dose of 15 µg/mL. Results suggest that co-encapsulation of Paclitaxel with Naringin in mixed micelles is an effective strategy for achieving its higher anticancer activity.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Portadores de Fármacos/síntese química , Flavanonas/administração & dosagem , Neoplasias/tratamento farmacológico , Paclitaxel/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/farmacocinética , Composição de Medicamentos/métodos , Desenho de Drogas , Liberação Controlada de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Estabilidade de Medicamentos , Flavanonas/farmacocinética , Humanos , Células MCF-7 , Micelas , Paclitaxel/farmacocinética , Polímeros/síntese química
20.
Spectrochim Acta A Mol Biomol Spectrosc ; 206: 135-140, 2019 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-30096697

RESUMO

Gold nanoparticles (AuNPs) stabilized by new cationic 1­(3­(acetylthio)propyl)pyrazin­1­ium ligand (PPTA) were synthesized. AuNPs stabilized by PPTA (PPTA-AuNPs) were found to be spherical and polydispersed with the average size of 60 nm. Human neuroblastoma (SHSY-5Y) cells permeability of PPTA-AuNPs was found to be a key feature to study the intracellular quenching of Fe(III) proliferative activity. In vitro MTT assay revealed non-cytotoxicity of PPTA and PPTA-AuNPs at 100 µM concentration, while treatment of 100 µM of Fe(III) with SHSY-5Y cells resulted into higher cells viability. Contrary, a mixture of 1:1 Fe(III) with PPTA-AuNPs showed no change in the viability of cells at same concentration which suggests the intracellular complexation and recognition of Fe(III) by PPTA-AuNPs. AFM morphological analysis of SHSY-5Y cells also supported the MTT assay results, and it is safe to conclude that PPTA-AuNPs can be used as Fe(III) probes in living cells. In addition, Fe(III) caused a significant decrease in the absorbance of surface plasmon resonance (SPR) band of PPTA-AuNPs in a wide range of concentration and pH, with limit of detection 4.3 µM. Moreover, the specific response of PPTA-AuNPs towards Fe(III) was unaffected by the interference of other metals and components of real samples of tap water.


Assuntos
Antineoplásicos/química , Compostos Férricos/análise , Neuroblastoma/metabolismo , Pirazinas/química , Compostos de Sulfidrila/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ouro/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química
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