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1.
J Chem Theory Comput ; 15(9): 5103-5115, 2019 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-31402649

RESUMO

Intrinsically disordered proteins (IDPs) play key roles in biology and disease, rationalizing the wide interest in deriving accurate solution ensembles of IDPs. Molecular dynamics (MD) simulations of IDPs often suffer from force-field inaccuracies, suggesting that simulations must be complemented by experimental data to obtain physically correct ensembles. We present a method for integrating small-angle X-ray scattering (SAXS) data on-the-fly into MD simulations of disordered systems, with the aim to bias the conformational sampling toward agreement with ensemble-averaged SAXS data. By coupling a set of parallel replicas to the data and following the principle of maximum entropy, this method applies only a minimal bias. Using the RS peptide as a test case, we analyze the influence of (i) the number of parallel replicas, (ii) the scaling of the force constant for the SAXS-derived biasing energy with the number of parallel replicas, and (iii) the force field. The refined ensembles are cross-validated against experimental 3JHN-Hα couplings and further compared in terms of Cα distance maps and secondary structure content. Remarkably, we find that the applied force field only has a small influence on the SAXS-refined ensemble, suggesting that incorporating SAXS data into MD simulations may greatly reduce the force-field bias.


Assuntos
Entropia , Proteínas Intrinsicamente Desordenadas/química , Simulação de Dinâmica Molecular , Espalhamento a Baixo Ângulo , Difração de Raios X , Conformação Proteica
2.
Int J Nanomedicine ; 14: 4741-4754, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456635

RESUMO

Background: Ipomoea batatas (L.) Lam.(Ib) has high content of various beneficial nutrients which helps in improving and maintaining human health. It is well known as a functional food and also a valuable source of unique natural products. It contains various phenolic and flavonoid bioactive compounds. Methods: In this study, using the outer peel of two varieties of Ib : Korean red skin sweet potato and Korean pumpkin sweet potato, silver nanoparticles (AgNPs) were synthesized (termed Ib1-AgNps and Ib2-AgNps), respectively. Characterization of Ib1-AgNPs and Ib2-AgNPs was carried out through scanning electron microscopy, Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray analysis, X-ray powder diffraction and UV-Vis spectroscopy. Further, the bio-potential of the synthesized AgNPs was investigated by antidiabetic (α-glucosidase assay), antioxidant (free radical scavenging assays), antibacterial (disc diffusion method) and cytotoxicity assays (cell viability against HepG2 cells). Results: FT-IR spectroscopy revealed the contribution of bioactive compounds existing in Ib1 and Ib2 extracts, in the biosynthesis and equilibrium of the AgNPs. Although the Ib2-AgNPs had a higher atomic percentage of Ag in comparison with Ib1-AgNPs, in the antidiabetic assay, the inhibition percentage of α-glucosidase was higher for AgNPs of Ib1 than Ib2, at all three concentrations examined. From the cytotoxicity results, HepG2 cancer cells were more sensitive to the Ib1-AgNPs in comparison to the Ib2-AgNPs-treated HepG2 cells. The antioxidant prospective was higher in Ib2-AgNPs than Ib1-AgNPs. Moreover, the Ib2-AgNPs showed inhibitory action against all five tested pathogenic bacteria, producing an inhibition zone of 8.74-11.52 mm while Ib1-AgNPs had an inhibitory effect on four of them, with an 8.67-11.23 (mm) inhibition zone. Conclusions: Overall, the results concluded that the Ib2-AgNPs exhibited relatively higher functional activity than Ib1-AgNPs, which might be credited to the greater abundance of bioactive compounds existing in Ib2 extract that acted as reducing as well as capping agents in the synthesis of Ib2-AgNPs. Overall, the current study highlights a novel cost-effective and eco-friendly AgNPs synthesis using food waste peels with biocompatibility and could be potentially utilized in biomedical and pharmaceutical industries.


Assuntos
Antibacterianos/farmacologia , Antioxidantes/farmacologia , Ipomoea batatas/química , Nanopartículas Metálicas/química , Prata/farmacologia , Bactérias/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Células Hep G2 , Humanos , Hipoglicemiantes/farmacologia , Concentração Inibidora 50 , Nanopartículas Metálicas/ultraestrutura , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , alfa-Glucosidases/metabolismo
3.
Int J Nanomedicine ; 14: 4911-4929, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31456637

RESUMO

Background: Apocynin (APO) is a bioactive phytochemical with prominent anti-inflammatory and anti-oxidant activities. Designing a nano-delivery system targeted to potentiate the gastric antiulcerogenic activity of APO has not been investigated yet. Chitosan oligosaccharide (COS) is a low molecular weight chitosan and its oral nanoparticulate system for potentiating the antiulcerogenic activity of the loaded APO has been described here. Methods: COS-nanoparticles (NPs) loaded with APO (using tripolyphosphate [TPP] as a cross-linker) were prepared by ionic gelation method and fully characterized. The chosen formula was extensively evaluated regarding in vitro release profile, kinetic analysis, and stability at refrigerated and room temperatures. Ultimately, the in vivo antiulcerogenic activity against ketoprofen (KP)-induced gastric ulceration in rats was assessed by macroscopic parameters including Paul's index and antiulcerogenic activity, histopathological examination, immunohistochemical (IHC) evaluation of cyclooxygenase-2 (COX-2) expression level in ulcerated gastric tissue, and biochemical measurement of oxidative stress markers and nitric oxide (NO) levels. Results: The selected NPs formula with COS (0.5 % w/v) and TPP (0.1% w/v) was the most appropriate one with drug entrapment efficiency percentage of 35.06%, particle size of 436.20 nm, zeta potential of +38.20 mV, and mucoadhesive strength of 51.22%. It exhibited a biphasic in vitro release pattern as well as high stability at refrigerated temperature for a 6-month storage period. APO-loaded COS-NPs provoked marvelous antiulcerogenic activity against KP-induced gastric ulceration in rats compared with free APO treated group, which was emphasized by histopathological, IHC, and biochemical studies. Conclusion: In conclusion, APO-loaded COS-NPs could be considered as a promising oral phytopharmaceutical nanoparticulate system for management of gastric ulceration.


Assuntos
Acetofenonas/administração & dosagem , Acetofenonas/farmacologia , Quitosana/química , Mucosa Gástrica/efeitos dos fármacos , Nanopartículas/química , Oligossacarídeos/química , Compostos Fitoquímicos/administração & dosagem , Compostos Fitoquímicos/farmacologia , Acetofenonas/uso terapêutico , Administração através da Mucosa , Animais , Biomarcadores/metabolismo , Varredura Diferencial de Calorimetria , Ciclo-Oxigenase 2/metabolismo , Liberação Controlada de Fármacos , Cinética , Masculino , Nanopartículas/ultraestrutura , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Tamanho da Partícula , Ratos Wistar , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática , Estômago/efeitos dos fármacos , Estômago/patologia , Úlcera Gástrica/tratamento farmacológico , Úlcera Gástrica/patologia , Suínos , Difração de Raios X
4.
Int J Nanomedicine ; 14: 4975-4989, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371942

RESUMO

The porous surface of a polyetheretherketone (PK)-nanoporous lithium-doped magnesium silicate (NLS) blend (PKNLS) was fabricated on a PK surface by layer-by-layer pressuring, sintering, and salt-leaching. As controls, porous surfaces of a PK/lithium-doped magnesium silicate blend (PKLS) and PK were fabricated using the same method. The results revealed that porosity, water absorption, and protein absorption of the porous surface of PKNLS containing macropores and nanopores were obviously enhanced compared to PKLS and PK containing macropores without nanopores. In addition, PKNLS, with both macroporostiy and nanoporosity, displayed the highest ability of apatite mineralization in simulated body liquid, indicating excellent bioactivity. In vitro responses (including adhesion, proliferation, and differentiation) of MC3T3E1 cells to PKNLS were significantly enhanced compared to PKLS and PK. In vivo implantation results showed that new bone grew into the macroporous surface of PKNLS, and the amount of new bone for PKNLS was the highest. In short, PKNLS integration with PK significantly promoted cells/bone-tissue responses and exhibited excellent osteogenesis in vivo, which might have great potential for bone repair.


Assuntos
Osso e Ossos/fisiologia , Cetonas/farmacologia , Lítio/farmacologia , Silicatos de Magnésio/farmacologia , Nanoporos , Osteoblastos/citologia , Polietilenoglicóis/farmacologia , Adsorção , Fosfatase Alcalina/metabolismo , Animais , Apatitas/química , Osso e Ossos/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Imagem Tridimensional , Masculino , Camundongos , Nanoporos/ultraestrutura , Osteoblastos/efeitos dos fármacos , Osteoblastos/ultraestrutura , Osteogênese/efeitos dos fármacos , Porosidade , Coelhos , Água/química , Difração de Raios X
5.
Int J Nanomedicine ; 14: 5147-5157, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31371953

RESUMO

Background: Kaempferol (K) is a recognized anticancer drug that can conjugate with small-size gold nanoclusters (AuNCs). Materials and methods: K-AuNCs were synthesized and their use as an anticancer drug was explored using A549 lung cancer cells. Colony formation and cell migration assays were carried out. The morphology of the K-AuNCs treated A549 cells was explored using bio-atomic force microscopy. Results: The K-AuNCs were 1-3 nm in diameter and emitted strong fluorescent at 650 nm following excitation at 550 nm. The stretching and bending nature of the K-AuNCs were analyzed by the Fourier transform infrared spectroscopy. The presence of kaempferol in the AuNCs were confirmed by the PL spectroscopy. Conclusion: The synthesized K-AuNCs mainly targeted and damaged the nuclei of the cancer cells. This composite nanocluster was less toxicity to the normal human cell and higher toxicity to the A549 lunch cancer cell and these material is potential for anticancer drug delivery and bio imaging applications.


Assuntos
Antineoplásicos/uso terapêutico , Ouro/química , Quempferóis/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas Metálicas/química , Células A549 , Antineoplásicos/química , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/patologia , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Humanos , Quempferóis/farmacologia , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/ultraestrutura , Fenômenos Ópticos , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
6.
Int J Nanomedicine ; 14: 5381-5396, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409994

RESUMO

Background: Tacrolimus (TCR), also known as FK-506, is a biopharmaceutics classification system (BCS) class II drug that is insoluble in water because of its high log P values. After dermal application, TCR remains in the stratum corneum and passes through the skin layers with difficulty. Purpose: The objectives of this study were to develop and evaluate solid lipid nanoparticles (SLNs) with thermosensitive properties to improve penetration and retention. Methods: We prepared TCR-loaded thermosensitive solid lipid nanoparticles (TCR-SLNs) with different types of surfactants on the shell of the particle, which conferred the advantages of enhancing skin permeation and distribution. We also characterized them from a physic point of view and performed in vitro and in vivo evaluations. Results: The TCR contained in the prepared TCR-SLN was in an amorphous state and entrapped in the particles with a high loading efficiency. The assessment of ex vivo skin penetration using excised rat dorsal skin showed that the TCR-SLNs penetrated to a deeper layer than the reference product (0.1% Protopic®). In addition, the in vivo skin penetration test demonstrated that TCR-SLNs delivered more drug into deeper skin layers than the reference product. FT-IR images also confirmed drug distribution of TCR-SLNs into deeper layers of the skin. Conclusion: These results revealed the potential application of thermosensitive SLNs for the delivery of difficult-to-permeate, poorly water-soluble drugs into deep skin layers.


Assuntos
Derme/metabolismo , Lipídeos/química , Nanopartículas/química , Tacrolimo/farmacologia , Temperatura Ambiente , Administração Cutânea , Animais , Varredura Diferencial de Calorimetria , Derme/efeitos dos fármacos , Liberação Controlada de Fármacos , Irritantes/toxicidade , Nanopartículas/ultraestrutura , Tamanho da Partícula , Coelhos , Ratos Sprague-Dawley , Absorção Cutânea/efeitos dos fármacos , Testes Cutâneos , Espectroscopia de Infravermelho com Transformada de Fourier , Tensoativos/química , Difração de Raios X
7.
Int J Nanomedicine ; 14: 5435-5448, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31409997

RESUMO

Background: Ramipril (RMP) suffers from poor aqueous solubility along with sensitivity to mechanical stress, heat, and moisture. The aim of the current study is to improve RMP solubility and stability by designing solid self-nanoemulsifying drug delivery system (S-SNEDDS) as tablet. Methods: The drug was initially incorporated in different liquid formulations (L-SNEDDS) which were evaluated by equilibrium solubility, droplet size, and zeta potential studies. The optimized formulation was solidified into S-SNEDDS powder by the adsorbent Syloid® and compressed into a self-nanoemulsifying tablet (T-SNEDDS). The optimized tablet was evaluated by drug content uniformity, hardness, friability, disintegration, and dissolution tests. Furthermore, pure RMP, optimized L-SNEDDS, and T-SNEDDS were enrolled in accelerated and long-term stability studies. Results: Among various liquid formulations, F5 L-SNEDDS [capmul MCM/transcutol/HCO-30 (25/25/50%w/w)] showed relatively high drug solubility, nano-scaled droplet size, and high negative zeta potential value. The optimized SNEDDS solidification with Syloid® at ratio (1:1) resulted in a compressible powder with an excellent flowability. The optimized tablet (T-SNEDDS) showed accepted content uniformity, hardness, friability, and disintegration time (<15 minutes). The optimized L-SNEDDS, S-SNEDDS, and T-SNEDDS showed superior enhancement of RMP dissolution compared to the pure drug. Most importantly, T-SNEDDS showed significant (P<0.05) improvement of RMP stability compared to the pure drug and L-SNEDDS in both accelerated and long-term stability studies. Conclusion: RMP-loaded T-SNEDDS offers a potential oral dosage form that provides combined improvement of RMP dissolution and chemical stability.


Assuntos
Sistemas de Liberação de Medicamentos , Emulsões/química , Nanopartículas/química , Ramipril/farmacologia , Administração Oral , Adsorção , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Dureza , Nanopartículas/ultraestrutura , Tamanho da Partícula , Controle de Qualidade , Solubilidade , Eletricidade Estática , Comprimidos/química , Fatores de Tempo , Difração de Raios X
8.
Ecotoxicol Environ Saf ; 182: 109396, 2019 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-31276888

RESUMO

We report herein the sonochemical synthesis of a lanthanum dioxide carbonate (La2O2CO3) and zinc ferrite (ZnFe2O4)-loaded reduced graphene oxide (LZF-rGO) nanoheterostructure for ultrasound (US)-assisted degradation of methyl orange (MO) from water. The MO was chosen as a model organic dye due to its toxicological and biodegradable-resistant properties. The LZF-rGO catalyst was characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The results of characterizations confirmed successful synthesis of sonocatalyst. Among different removal systems, US/LZF-rGO displayed outstanding sonodegradation performance for degradation of MO. The maximum removal efficiency of 75.9% was achieved using 0.2 g/L sonocatalyst, 20 mg/L MO, and 0.71 W/cm2 US power intensity for 65 min. MO can be partially adsorbed on LZF-rGO but mostly sonodegraded by reactive radical species. The reaction conditions were optimized by investigating the effect of key operating parameters, including the sonocatalyst dosage, initial MO concentration, US power intensity, presence of inorganic salts, and use of an enhancer, on the decolorization of MO. The degradation intermediates produced from MO during the sonocatalytic process were identified by UPLC®/MS-MS, and possible mechanism and pathway for the degradation of MO in the US/LZF-rGO system were also proposed. Reusability experiments with this sonocatalyst revealed a less than 10% drop in the degradation efficiency after four adsorption-desorption cycles.


Assuntos
Corantes/química , Grafite/química , Lantânio/química , Nanoestruturas/química , Poluentes Químicos da Água/química , Carbonatos , Catálise , Compostos Férricos , Magnetismo , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Modelos Químicos , Óxidos/química , Espectroscopia Fotoeletrônica , Água , Difração de Raios X , Zinco , Compostos de Zinco , Óxido de Zinco/química
9.
J Chromatogr A ; 1602: 168-177, 2019 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-31303311

RESUMO

In this work, we presented the preparation of magnetic carbon nanotubes (MCNTs) functionalized with molecularly imprinted polymers (MIPs) for effective removal of aristolochic acid I (AAI) in traditional Chinese medicine (TCM). MCNTs@AAI-MIPs was obtained via a facile and environmental friendly sol-gel process. Firstly, MCNTs were synthesized by a solvothermal method. Then, the template molecules were self-assembled with the functional monomer phenyltrimethoxysilane (PTMOS) in the presence of ethanol and water. Finally, AAI-MIPs film was coated on the MCNTs to obtain product MCNTs@AAI-MIPs using tetraethyl-orthosilicate (TEOS) as cross-linker. The morphology and structure of prepared MIPs were characterized by Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), nitrogen gas adsorption and vibrating sample magnetometer (VSM). The adsorption properties were demonstrated by kinetic, isothermal and selective adsorption experiments. The results showed that the imprinted nanocomposites exhibited fast separation rate (10 s), high adsorption capacity (18.54 µg∙mg-1), short kinetic equilibrium time (15 min), and good selectivity to template molecule with imprinting factor (IF) of 3.17. A regression equation (y=57294x-4734.1) with good linearity was obtained in the concentration range of 0.1-200 µg∙mg-1 for AAI with a correlation coefficient (R2) of 0.9998. The limit of detection (LOD, S/N=3) was 0.034 µg∙mg-1. Moreover, high recoveries ranged from 80% to 110% (RSD=3.27%-8.16%) were received in spiked TCM samples. The results suggested that the proposed MCNTs@AAI-MIPs could efficiently and specifically capture AAI from an actual complex TCM samples.


Assuntos
Ácidos Aristolóquicos/isolamento & purificação , Magnetismo , Impressão Molecular/métodos , Nanotubos de Carbono/química , Polímeros/química , Adsorção , Cinética , Nanotubos de Carbono/ultraestrutura , Nitrogênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Temperatura Ambiente , Difração de Raios X
10.
World J Microbiol Biotechnol ; 35(8): 114, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332537

RESUMO

N-acetyl-D-glucosamine (GlcNAc) is an important amino-monosaccharide with great potential for biotechnological applications. It has traditionally been produced by the chemical hydrolysis of chitin, despite certain industrial and environmental drawbacks, including acidic wastes, low yields and high costs. Therefore, enzymatic production has gained attention as a promising environmentally-friendly alternative to the chemical processes. In this study we demonstrate the GlcNAc bioproduction from colloidal α-chitin using an enzyme cocktail containing endochitinases and exochitinases (chitobiosidases and N-acetyl-glucosaminidases). The enzyme cocktail was extracted after fermentation in a bioreactor by Aeromonas caviae CHZ306, a chitinolytic marine bacterium with great potential for chitinase production. Hydrolysis parameters were studied in terms of temperature, pH, enzyme and substrate concentration, and reaction time, achieving over 90% GlcNAc yield within 6 h. The use of colloidal α-chitin as substrate showed a substantial improvement of GlcNAc yields, when compared with ß-chitin and α-chitin polymorphs. Such result is directly related to a significant decrease in crystallinity and viscosity from natural α-chitin, providing the chitinase with greater accessibility to the depolymerized chains. This study provides valuable information on the GlcNAc bioproduction from chitin using an enzymatic approach, addressing the key points for its production, including the enzyme cocktail composition and the substrate structures.


Assuntos
Acetilglucosamina/biossíntese , Aeromonas caviae/enzimologia , Quitina/metabolismo , Quitinases/metabolismo , Meios de Cultura/química , Concentração de Íons de Hidrogênio , Hidrólise , Espectroscopia de Ressonância Magnética , Peso Molecular , Temperatura Ambiente , Viscosidade , Difração de Raios X
11.
Waste Manag Res ; 37(9): 914-924, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31315552

RESUMO

The asbestos-containing waste management is a public health topic for countries which have used this mineral. Treatment of chrysotile (white asbestos), a phyllosilicate from serpentine, crocidolite (blue asbestos, first results on this kind of asbestos), one of the five asbestos varieties of amphibole family and asbestos-containing waste conversion process is proposed by using hydrothermal treatment in supercritical water. All samples were treated in an Inconel Batch Reactor. The treatment durations range is from 1 to 6 hours, temperatures range is from 400°C to 750°C, mass concentration range is from 0.02 to 170 mg. mL-1 and pressures are higher than 23 MPa. Ultrapure water is used for sample preparation. This ultrapure water is used to monitor mineral leaching on the aqueous phase and to avoid particle cross-contamination. Transmission electron microscopy analyses were carried out to check the presence or not of asbestos phase. According to these analyses, the best conditions of conversion were 1 hour and 0.02 mg. mL-1 for chrysotile, 3 hours and 0.02 mg. mL-1 for crocidolite and 1 hour and 20 mg. mL-1 for asbestos-containing waste, at T = 750°C. Supercritical water conditions were maintained during the whole treatment. The X-ray diffraction showed that the main phases present after treatments were riebeckite and magnetite (crocidolite), forsterite and enstatite (chrysotile), and calcite, spurrite and gehlenite (asbestos-containing waste). Finally, a scanning electron microscopy analysis was performed to monitor morphological fibre change. The elongated structure, partially fragmented, was found in all samples.


Assuntos
Asbesto Crocidolita , Asbestos , Asbestos Serpentinas , Microscopia Eletrônica de Varredura , Difração de Raios X
12.
Int J Nanomedicine ; 14: 4949-4960, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308665

RESUMO

Purpose: The objective of this study was to exploit a novel methotrexate (MTX)-loaded solid self-microemulsifying drug delivery system (SMEDDS) with enhanced bioavailability and photostability. Materials and methods: The optimized liquid SMEDDS was composed of castor oil, Tween® 80, and Plurol® diisostearique at a voluminous ratio of 27:63:10. The solid SMEDDS was formulated by spray drying liquid SMEDDS with the solid carrier (calcium silicate). Particle size analyzer, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), powder X-ray diffraction (PXRD), and Fourier transform infrared (FTIR) spectroscopy experiments characterized the physiochemical properties of the MTX-loaded solid SMEDDS. These properties include a z-average diameter of emulsion around 127 nm and the amorphous form of the solid SMEDDS. Furthermore, their solubility, dissolution, and pharmacokinetics in Sprague-Dawley rats were analyzed in comparison with the MTX powder. Results: The final dissolution rate and required time for complete release of solid SMEDDS were 1.9-fold higher and 10 min shorter, respectively, than those of MTX powder. Pharmacokinetic analysis demonstrated 2.04- and 3.41-fold increments in AUC and Cmax, respectively in comparison to MTX powder. The AUC and Cmax were significantly increased in solid SMEDDS. Finally, the photostability studies revealed the substantially enhanced photostability of the MTX-loaded SMEDDS under the forced degradation and confirmatory conditions. Conclusion: This solid SMEDDS formulation could be an outstanding candidate for improving the oral bioavailability and photostability of MTX.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Emulsões/química , Luz , Metotrexato/administração & dosagem , Metotrexato/farmacologia , Administração Oral , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Metotrexato/sangue , Metotrexato/farmacocinética , Petróleo , Transição de Fase , Ratos Sprague-Dawley , Solubilidade , Difração de Raios X
13.
Zhongguo Zhong Yao Za Zhi ; 44(11): 2236-2243, 2019 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-31359648

RESUMO

The single-factor test was used to optimize the high-pressure homogenization method to prepare the phenolic extract nanosuspensions(DBNs). The physicochemical properties of the obtained nanosuspensions were characterized and the cumulative release in vitro was evaluated. The results showed that the drug concentration was 0.5 g·L~(-1), the mass concentrations of PVPK30 and SDS were 0.5 and 0.25 g·L~(-1), respectively, the probe ultrasonic time was 5 min, the homogenization pressure was 900 bar, and the number of homogenization was 2 times. The prepared DBNs had an average particle size of(168.80±0.36) nm, polydispersity index(PDI) of 0.09±0.04, stability index(SI) of 0.85, and DBNs were stable for storage within 30 days. Scanning electron microscopy showed that the particle size of the dragon's blood extract was reduced and the uniformity was improved in the obtained nanosuspensions. X-ray diffraction pattern and differential scanning calorimetry showed that the phenolic extract of dragon's blood was still in an amorphous state after being prepared into nanosuspensions. The results of saturated solubility measurement showed that the solubility of DBNs lyophilized powder reached 6.25 g·L~(-1), while the solubility of DB raw powder was only 28.67 mg·L~(-1). The in vitro dissolution experiments showed that DBNs lyophilized powder accumulated in gastrointestinal fluid for 8 h. The release amount was 90%,the cumulative release of the raw powder in the gastrointestinal fluid for 24 h was less than 1%, and the solubility and dissolution rate of the DBNs lyophilized powder were significantly higher than the DB raw powder. The method is simple in process and convenient in operation, and can successfully prepare uniform and stable nanosuspensions to improve its solubility, and provides a research basis for solving the application limitation of dragon's blood extract.


Assuntos
Nanopartículas , Extratos Vegetais/química , Varredura Diferencial de Calorimetria , Tamanho da Partícula , Solubilidade , Suspensões , Difração de Raios X
14.
J Environ Manage ; 247: 698-711, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31279147

RESUMO

Silver being the precious metal, its recovery from the waste and utilization is a worthy attempt. The present study represents a very promising sustainable approach for the synthesis of silver nanoparticles (AgNPs), where prime raw materials are waste products (silver metal extracted from waste X-ray sheets and Sal deoiled seed cake (DOC), a plant-based waste as reducing-capping agent). Upon reaction of silver nitrate extracted from waste X-ray sheets and Sal DOC extract at room temperature, the characteristic yellowish-brown color appeared within 30 min. Peak at 485-495 in UV-visible spectrophotometer confirmed the synthesis of AgNPs. X-ray waste synthesized (XRWS) AgNPs were polycrystalline in nature and have face centered cubic (fcc) lattice. Majority of them were polygonal in shape (size range 30-150 nm) with some flower like aggregates as revealed by Transmission Electron Microscope. The XRWS-AgNPs were stabilized by organic groups adhered to their surface and had good stability with a zeta potential of -27.60 mV. These XRWS-AgNPs could work as an efficient catalyst for the reduction of five selected azo dyes individually as well as mixture of these dyes. The degraded products of the individual dyes were identified using Gas Chromatography Mass Spectroscopy. Experimental values obtained for dye degradation study were fitted with first and second order linear kinetic model to know about rate of the reaction.


Assuntos
Nanopartículas Metálicas , Biomassa , Corantes , Florestas , Resíduos Industriais , Extratos Vegetais , Prata , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X , Raios X
15.
Int J Nanomedicine ; 14: 4589-4599, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31296988

RESUMO

Purpose: Ferulic acid (FA) is a poorly water-soluble natural antioxidant with anticancer activity. This poor solubility limits the application of FA in the food and pharmaceutical industry. Cyclodextrin nanosponges (CD-NSs) are a novel group of cross-linked CD derivatives which can be used to enhance the solubility of low-soluble bioactive compounds. Methods: In this study, FA was encapsulated into the NSs in the proportion of 1:4 (FA:NS). Diphenyl carbonate was used as a cross-linker in different proportions with ß-CD. Characterization of obtained NSs was performed using scanning electron microscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) analysis. Results: Our results revealed that the solubility of encapsulated FA was increased up to fifteenfold compared with pure FA in the proportion of 1:4 (CD:cross-linker). The results of FTIR, XRD, and DSC confirmed the interaction of FA with NSs. The cytotoxicity of encapsulated FA against MCF7 and 4T1 breast cancer cell lines was investigated using different concentrations of FA in 24, 48, and 72 hrs. The cytotoxicity assay indicated that FA treatment reduced viability and enhanced apoptosis of cancer cells. IC50 value of encapsulated FA (250 ppm) was decreased by threefold when compared with pure FA (750 ppm). Conclusion: In general, CD-NS was found to be a suitable delivery system for poorly soluble bioactives such as FA.


Assuntos
Ácidos Cumáricos/química , Ácidos Cumáricos/farmacologia , Ciclodextrinas/química , Nanoestruturas/química , Antineoplásicos/química , Antineoplásicos/farmacologia , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Varredura Diferencial de Calorimetria , Linhagem Celular Tumoral , Liberação Controlada de Fármacos , Feminino , Humanos , Microscopia Eletrônica de Varredura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Difração de Raios X
16.
Food Chem ; 298: 125041, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261000

RESUMO

Edible packaging films play an important role in extending the shelf life of food products. In this work, the properties of cellulose nanofiber (CNF) reinforced hemicelluloses/chitosan-based edible films with xylooligosaccharides (XOS) have been evaluated. Results showed that the tensile strength (TS) of the film can be increased by 2.5 times with adding 5 wt% CNF. Incorporating 1.79-7.18% XOS into hemicelluloses-chitosan matrix only caused slightly higher water vapor permeability, and the composite films exhibited good hydrophobicity, thermal stability, and high transparency. The hemicelluloses/chitosan films with 1.79-5.38% XOS had higher TS (42.7-50.7 MPa) and lower oxygen permeability (OP, 4.95-5.06 cm3 µm/m2·day·kPa) than those containing 7.18% XOS. Additionally, ∼92.6% XOS in films can be released in simulated gastric fluid within 60 min. Overall, XOS (1.79-5.38%) with prebiotic properties can be added to films successfully to improve the functionality and the films were fit for food-packaging where high TS and low OP are required.


Assuntos
Celulose/química , Quitosana/química , Glucuronatos/química , Nanofibras/química , Oligossacarídeos/química , Embalagem de Alimentos/métodos , Suco Gástrico , Humanos , Microscopia Eletrônica de Varredura , Permeabilidade , Polissacarídeos/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Vapor , Resistência à Tração , Difração de Raios X
17.
Food Chem ; 298: 124982, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31261014

RESUMO

This work studies the physicochemical properties of quinoa flour and isolated starch. Starch in the seed forms clusters rich in amylopectin that are immersed in a matrix with spherical and polygonal shapes in the submicron scale. The isolated quinoa starch is rich in Sulphur and Magnesium. The quinoa flour has a higher content of protein, carbohydrates and lipids than isolated starch. Water absorption and water solubilized indexes of starch exhibited high values that could had originated by the extraction method. The broad peaks found for the X-ray patterns of isolated quinoa starch indicate that amylose and amylopectin are composed by nanocrystals, according to the PDF-4+2019 software. The viscosity of isolated starch had a higher value than flour; therefore, the quinoa starch could be used as a thickener in different formulations with the advantage of keeping a significant presence of minerals which are important to the human health.


Assuntos
Chenopodium quinoa/química , Farinha/análise , Análise de Alimentos/métodos , Amido/química , Amilopectina/química , Amilose/análise , Microscopia Eletrônica de Varredura , Minerais/análise , Sementes/química , Sementes/ultraestrutura , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/análise , Amido/ultraestrutura , Temperatura Ambiente , Viscosidade , Água/química , Difração de Raios X
18.
AAPS PharmSciTech ; 20(6): 252, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300965

RESUMO

The objective of the present study was to investigate the effect of partially hydrolyzed ginsenoside on the physicochemical properties and in vitro release of curcumin from phospholipid-based nanostructured lipid carrier (NLC). NLC formulas modified with partially hydrolyzed ginsenoside (NLC-PG) were prepared with different amounts of ginsenoside using the conventional hot-melt method. The average particle size of curcumin-loaded NLC-PG ranged from 150 to 200 nm, and polydispersity index was in the range of 0.101-0.177, indicating monodispersed particle size distribution. Optical microscopy showed no sedimentation or recrystallization of curcumin even at 10,000 µg/ml concentration as NLC-PG in distilled water, indicating significantly enhanced solubility. TEM image showed that the nanoparticles were monodispersed with a multilayered core/shell structure. X-ray diffraction and FTIR spectroscopy showed that curcumin was amorphous in the NLC-PG, and there was no interaction between curcumin and the excipients. In vitro release study using simulated gastric/intestinal fluid media revealed that the release rate (Jss) of curcumin from the NLC-PG increased as a function of the ginsenoside content in the lipid carrier. Moreover, the Jss of curcumin kept gradually increasing in the presence of lipase, whereas in the presence of viscozyme, it sharply increased until the ginsenoside content reached 9.09% and subsequently plateaued. Partially hydrolyzed ginsenoside increased the Jss of curcumin from curcumin-loaded NLC-PG and therefore may be useful for improving the bioavailability of curcumin.


Assuntos
Curcumina/química , Portadores de Fármacos/química , Ginsenosídeos/química , Lipídeos/química , Nanoestruturas/química , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Curcumina/farmacocinética , Portadores de Fármacos/farmacocinética , Excipientes/química , Excipientes/farmacocinética , Ginsenosídeos/farmacocinética , Hidrólise , Lipídeos/farmacocinética , Lisofosfatidilcolinas/química , Lisofosfatidilcolinas/farmacocinética , Tamanho da Partícula , Fosfatidilcolinas/química , Fosfatidilcolinas/farmacocinética , Óleo de Soja/química , Óleo de Soja/farmacocinética , Difração de Raios X/métodos
19.
Int J Nanomedicine ; 14: 2693-2703, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31354260

RESUMO

Background: Silver, incorporation with natural or synthetic polymers, has been used as an effective antibacterial agent since decades. Silver has potential applications in healthcare especially in nanoparticles form but silver sulfadiazine (AgSD) is the most efficient antibacterial agent especially for burn wound dressings. Method: In this report, mechanical, structural, and antibacterial properties of PAN nanofibers incorporation with silver sulfadiazine are mainly focused. AgSD was loaded for the first time on electrospinning as well as self-synthesized AgSD on PAN nanofibers by solution immersion method and then compared the results of both. Results: Occurrence of chemical reaction among the functional groups of AgSD and PAN were analyzed using FTIR, for both types of specimen. Morphological and surface properties of prepared nanofiber mats were characterized by scanning electron microscope, and it resulted in uniform nanofibers without bead formation. Diameter of nanofibers was slightly increased with addition of AgSD by in situ and immersion methods respectively. Nanoparticles distribution was analyzed by transmission electron microscopy. Thermal properties were analyzed by thermo-gravimetric analyzer and it was observed that AgSD decreased thermal stability of PAN which is better from biomedical perspective. X-ray diffraction declared crystalline structure of nanofiber mats. Presence of Ag and S contents in nanofiber mats was analyzed by X-ray photo spectroscopy. Antibacterial properties of nanofiber mats were investigated by disc diffusion method was carried out. E. coli and Bacillus bacteria strain were used as gram-negative and gram-positive respectively. Zone inhibition of the bacteria was used as a tool to determine effectiveness of AgSD released from PAN nanofiber mats. The antibacterial properties of PAN nanofibers impregnated with AgSD were determined with both types of bacteria strains to compare with control one. Conclusion: On the basis of characterization results it is concluded that PAN/AgSD (immersion) nanofiber mats have better structural and antibacterial properties than that of PAN/AgSD (in situ) nanofiber mats. So, from our point of view, self-synthesized AgSD is recommended for further production of nanofiber mats for antibacterial applications.


Assuntos
Resinas Acrílicas/química , Antibacterianos/farmacologia , Nanofibras/química , Sulfadiazina de Prata/farmacologia , Bacillus/efeitos dos fármacos , Módulo de Elasticidade , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Nanofibras/ultraestrutura , Espectroscopia Fotoeletrônica , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Resistência à Tração , Termogravimetria , Difração de Raios X
20.
Food Chem ; 298: 125081, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31260952

RESUMO

The impact of kansui on the dough rheology and quality characteristics of chickpea-wheat composite flour-based noodles was investigated. For noodle dough, both the relative crystallinity and degree of order obtained from X-ray diffraction and Fourier transform infrared spectroscopy increased with the low level of kansui addition (0.5-1.5%), followed by a decreased trend at higher levels of alkali concentration (2.0-3.0%). Such variation was in accordance with the trend observed for G' and G″. Based on the confocal laser scanning microscopic observation for cooked noodle samples, the low concentration of kansui addition (0.5-1.5%) protected the well-embedded starch granules being disassociate from the gluten network, whereas with the increased alkali addition (2.0-3.0%), the protein network was impaired with a greater amount of ruptured starch granules being disassociated from the gluten network. The observation corresponded well with the electrophoretic profile, and the results of cooking properties, -SH content, and textural properties of cooked noodles.


Assuntos
Cicer/química , Farinha , Triticum/química , Carbonatos/química , Culinária , Qualidade dos Alimentos , Glutens/química , Microscopia Confocal , Potássio/química , Reologia , Espectroscopia de Infravermelho com Transformada de Fourier , Amido/química , Difração de Raios X
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