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1.
AAPS PharmSciTech ; 23(7): 270, 2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36171353

RESUMEN

This study investigates the development of atazanavir-concentrate loaded soft gelatin capsule for achieving enhanced atazanavir (ATV) concentration in plasma, brain, spleen, and lymphatics beneficial in the significant reduction of viral load in HIV infection. For this purpose, ATV-concentrate in the presence and absence of Soluplus with corn oil, oleic acid, tween 80, and propylene glycol was developed. The developed ATV-concentrate was found to have enhanced dispersibility with no signs of precipitation after dilution with simulated G.I fluid as evident from particle size (16.49±0.32 nm) and PDI (0.217±0.02) analysis. The rheological and molecular docking studies explainedthe reduction of viscosity of SuATV-C due to the intermolecular H-bond between ATV and Soluplus that helps to retard crystallization. The shell of the soft gelatin capsule retains its integrity when subjected to a folding endurance test on a texture analyzer depicting that the concentrate did not affect the integrity of the soft gelatin capsule shell. An ex vivo and in vivo pharmacokinetic study in rats revealed that the SuATV-C soft gelatin capsule (SuATV-C SGC) indicated 2.9 fold improvement in rate and extent of permeation and absorption than that of ATV-suspension. The tissue distribution study also exhibited higher drug concentration in the brain (2.5 fold), lymph nodes (2.7 fold), and spleen (1.2 fold) administered with SuATV-C SGC, revealing the overwhelming influence of Soluplus and corn oil. In a nutshell, these studies demonstrated that SuATV-C SGC seems to have the potential to deliver an anti-retroviral drug to the viral sanctuaries for the better management of HIV.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Animales , Fármacos Anti-VIH/farmacocinética , Sulfato de Atazanavir/farmacocinética , Sulfato de Atazanavir/uso terapéutico , Encéfalo , Aceite de Maíz/uso terapéutico , Gelatina , Infecciones por VIH/tratamiento farmacológico , Simulación del Acoplamiento Molecular , Ácido Oléico , Polietilenglicoles , Polisorbatos , Polivinilos , Glicoles de Propileno , Ratas , Bazo
2.
Int J Biol Macromol ; 220: 766-774, 2022 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-35987360

RESUMEN

Polyvinylidene fluoride (PVDF) is commonly used in the chemical, electronic, and petrochemical industries because of its chemical and physical attributes. This study aimed to make novel PVDF-based composite with a high loading of silanized wood powder and micro/nanocellulose fibers, where glycerol acts as both a dispersant and a plasticizer all-in-one composite application for the first time. The purpose was also extended to systematically investigate their mechanical properties and melt flow. Results have demonstrated the efficiency of utilizing the cellulose fibers in bio-composites. With the addition of 30 wt% of filling materials, When the content of silanized cellulose fibers in glycerol dispersion is 25 wt%, the flexural strength and tensile strength reach the maximum value 72.30 MPa and 52.28 MPa. The experimental results indicate that silanized micro/nanocellulose fiber-reinforced PVDF/wood composites are a promising composite formula to help improve performance and reduce costs. It is an excellent example of utilizing biomass resources as a renewable/recyclable, sustainable and low-cost material to reduce the use of petroleum-based polymer, and improve the mechanical properties of composites.


Asunto(s)
Petróleo , Madera , Celulosa/química , Polímeros de Fluorocarbono , Glicerol/análisis , Ensayo de Materiales , Petróleo/análisis , Plastificantes , Polímeros/química , Polivinilos , Polvos , Madera/química
3.
J Biochem Mol Toxicol ; 36(10): e23167, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35861501

RESUMEN

The present research was designed to investigate the potential effects of zinc oxide nanoparticles synthesized by both chemical and green method in caprine testis. In this study, rod-shaped zinc oxide nanoparticles (ZnONPs) with diameter less than 100 nm were prepared by chemical and green method using polyvinyl pyrrolidone (PVP) and Ocimum sanctum leaf extract as stabilizing agents respectively. X-ray diffraction, Fourier transform infrared spectroscopy, LCMS, field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and EDX were utilized to characterize the synthesized zinc oxide nanoparticles. The histomorphological alterations of both chemically synthesized and biosynthesized zinc oxide nanoparticles were evaluated after administration of two doses (10 µg/ml and 20 µg/ml) for exposure duration of 4 h and 8 h. Chemically synthesized zinc oxide nanoparticles induced significant damage in testicular cells in dose and time-dependent manner. The Histomorphological changes included desquamation in germinal epithelium, pyknosis in germ cells, increased vacuolization, loss of mature spermatozoa from lumen and wide interstitial space between seminiferous tubules. Protective effects of biosynthesized zinc oxide nanoparticles were recorded at lower dose whereas some alterations were observed when treated with 20 µg/ml for 4 h and 8 h culture duration. The results confirmed that phytochemicals present in leaf extract of O. sanctum mitigated the zinc oxide nanoparticles induced toxicity, proving biosynthesized nanoparticles are better than chemically synthesized nanoparticles.


Asunto(s)
Nanopartículas del Metal , Nanopartículas , Óxido de Zinc , Animales , Antibacterianos/farmacología , Excipientes , Cabras , Masculino , Nanopartículas del Metal/química , Nanopartículas/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Polivinilos , Pirrolidinonas , Espectroscopía Infrarroja por Transformada de Fourier , Testículo , Óxido de Zinc/química , Óxido de Zinc/toxicidad
4.
Talanta ; 240: 123168, 2022 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-34954614

RESUMEN

Monitoring of uranium in the environment using the Diffusive Gradients in Thin-films (DGT) technique gains in importance as it can provide unique information about the bioavailability of the element and allows its long-term in-situ measurement. Hence, in this study, four DGT binding phases (Chelex-100, Dow-PIWBA, Diphonix, and Lewatit FO 36 resins) were evaluated for uranium monitoring to assess the robustness of their performance in estuarine and marine environments. These DGTs were deployed along the Scheldt estuary (Belgium and the Netherlands) over four campaigns between 2014 and 2021. The DGT performance (ratio of the DGT-determined vs. dissolved U concentration in grab water sample) varied with the water salinity. The Chelex-100 DGTs generally provided good performance in freshwater (median ratios close to 1.0), but an inverse correlation with the increasing salinity was observed (median ratios 0.7 at the stations with salinity >5). The Lewatit FO 36 DGTs provided good performance in the salinity range 0-18 (median ratios 1.0). However, a strong negative influence was observed at stations with high salinity levels (>18, ratio 0.6) and during the long-term deployment in seawater (ratios <0.5 over deployment periods ≥2 days). The Dow-PIWBA and Diphonix DGTs provided overall similar results with excellent performances along the whole salinity gradient (median ratios 1.1 and 1.0, respectively). Nevertheless, the long-term deployment trial in seawater (salinity ∼27) revealed the robustness of Diphonix DGTs that provided outstanding results even after 28 days of deployment (ratio 1.0). The differences in the performance of tested DGT resins were mostly given by the changes of U speciation along the salinity gradient. The speciation modelling of U showed that calcium uranyl carbonate complexes dominate along the Scheldt estuary (from 97 to 86% seawards) with increasing fraction of UO2(CO3)34- (from 2 to 14%) towards the mouth.


Asunto(s)
Uranio , Contaminantes Químicos del Agua , Difusión , Monitoreo del Ambiente , Estuarios , Geles , Poliestirenos , Polivinilos , Salinidad , Uranio/análisis , Contaminantes Químicos del Agua/análisis
5.
Int Urogynecol J ; 33(7): 1989-1997, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34586438

RESUMEN

INTRODUCTION AND HYPOTHESIS: To study the mid-term safety and functional outcomes of transvaginal anterior vaginal wall prolapse repair using polyvinylidene fluoride (PVDF) mesh (DynaMesh®-PR4) by the double trans-obturator technique (TOT). METHODS: Between 2015 and 2020, we prospectively included women with symptomatic high-stage anterior vaginal wall prolapse with or without uterine prolapse or stress urinary incontinence (SUI) in the study. The patients underwent transvaginal repair of the prolapse using PVDF mesh in two medical centers. We followed all patients for at least 12 months. We recorded the characteristics of vaginal and sexual symptoms, urinary incontinence, and prolapse stage pre- and postoperatively using International Consultation on Incontinence Questionnaire-Vaginal Symptoms (ICIQ-VS), International Consultation on Incontinence Questionnaire-Urinary Incontinence-Short Form (ICIQ-UI-SF), and Pelvic Organ Prolapse Quantification (POP-Q) system, respectively. RESULTS: One hundred eight women were included in the final analysis with a mean follow-up time of 34.5 ± 18.6 months. The anatomical success was achieved in 103 (95.4%) patients. There was a significant improvement in patients' vaginal symptoms, urinary incontinence, and quality of life scores postoperatively (p < 0.0001). Only six patients (5.5%) had mesh extrusion, five of whom were managed successfully. The total rates of complications and de novo urinary symptoms were 21.3% and 7.4%, respectively. Significant pain was reported in 17 cases (15.7%). CONCLUSION: Our findings show that using PVDF mesh in the double TOT technique for anterior vaginal wall prolapse repair is a safe procedure with high anatomic and functional success rates and acceptable complication rates in mid-term follow-up.


Asunto(s)
Polímeros de Fluorocarbono/normas , Polivinilos/normas , Mallas Quirúrgicas , Incontinencia Urinaria/cirugía , Prolapso Uterino/cirugía , Femenino , Polímeros de Fluorocarbono/química , Estudios de Seguimiento , Humanos , Prolapso de Órgano Pélvico/complicaciones , Prolapso de Órgano Pélvico/cirugía , Polivinilos/química , Calidad de Vida , Mallas Quirúrgicas/efectos adversos , Mallas Quirúrgicas/clasificación , Resultado del Tratamiento
6.
Int J Mol Sci ; 22(23)2021 Dec 02.
Artículo en Inglés | MEDLINE | ID: mdl-34884855

RESUMEN

The predominant impediments to cutaneous wound regeneration are hemorrhage and bacterial infections that lead to extensive inflammation with lethal impact. We thus developed a series of composite sponges based on polyvinyl alcohol (PVA) inspired by marjoram essential oil and kaolin (PVA/marjoram/kaolin), adopting a freeze-thaw method to treat irregular wounds by thwarting lethal bleeding and microbial infections. Microstructure analyses manifested three-dimensional interconnected porous structures for PVA/marjoram/kaolin. Additionally, upon increasing marjoram and kaolin concentrations, the pore diameters of the sponges significantly increased, recording a maximum of 34 ± 5.8 µm for PVA-M0.5-K0.1. Moreover, the porosity and degradation properties of PVA/marjoram/kaolin sponges were markedly enhanced compared with the PVA sponge with high swelling capacity. Furthermore, the PVA/marjoram/kaolin sponges exerted exceptional antibacterial performance against Escherichia coli and Bacillus cereus, along with remarkable antioxidant properties. Moreover, PVA/marjoram/kaolin sponges demonstrated significant thrombogenicity, developing high thrombus mass and hemocompatibility, in addition to their remarkable safety toward fibroblast cells. Notably, this is the first study to our knowledge investigating the effectiveness of marjoram in a polymeric carrier for prospective functioning as a wound dressing. Collectively, the findings suggest the prospective usage of the PVA-M0.5-K0.1 sponge in wound healing for hemorrhage and bacterial infection control.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Vendajes , Hemostáticos/farmacología , Origanum/química , Animales , Antibacterianos/química , Antioxidantes/análisis , Antioxidantes/química , Hemostáticos/química , Humanos , Caolín/química , Ensayo de Materiales , Ratones , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Células 3T3 NIH , Extractos Vegetales/química , Extractos Vegetales/farmacología , Alcohol Polivinílico/química , Polivinilos/química , Polivinilos/farmacología , Espectroscopía Infrarroja por Transformada de Fourier , Termogravimetría
7.
J Chem Inf Model ; 61(9): 4537-4543, 2021 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-34519202

RESUMEN

The pervasive use of portable electronic devices, powered from rechargeable batteries, represents a significant portion of the electricity consumption in the world. A sustainable and alternative energy source for these devices would require unconventional power sources, such as harvesting kinetic/potential energy from mechanical vibrations, ultrasound waves, and biomechanical motion, to name a few. Piezoelectric materials transform mechanical deformation into electric fields or, conversely, external electric fields into mechanical motion. Therefore, accurate prediction of elastic and piezoelectric properties of materials, from the atomic structure and composition, is essential for studying and optimizing new piezogenerators. Here, we demonstrate the application of harmonic-covalent and reactive force fields (FF), Dreiding and ReaxFF, respectively, coupled to the polarizable charge equilibration (PQEq) model for predicting the elastic moduli and piezoelectric response of crystalline zinc oxide (ZnO) and polyvinylidene difluoride (PVDF). Furthermore, we parametrized the ReaxFF atomic interactions for Zn-F in order to characterize the interfacial effects in hybrid PVDF matrices with embedded ZnO nanoparticles (NPs). We capture the nonlinear piezoelectric behavior of the PVDF-ZnO system at different ZnO concentrations and the enhanced response that was recently observed experimentally, between 5 and 7 wt % ZnO concentrations. From our simulation results, we demonstrate that the origin of this enhancement is due to an increase in the total atomic stress distribution at the interface between the two materials. This result provides valuable insight into the design of new and improved piezoelectric nanogenerators and demonstrates the practical value of these first-principles based modeling methods in materials science.


Asunto(s)
Nanopartículas , Óxido de Zinc , Simulación de Dinámica Molecular , Polivinilos
8.
Small ; 17(36): e2102550, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34314097

RESUMEN

Despite the boom in the water-triggered electric power generation technologies, few attempts have been made with a broader horizonyielding the electricity from sweat, which is of great value for low-power-consumption wearable electronics. Here, an electromechanical coupling and humidity-actuated two-in-one humidity actuator-driven piezoelectric generator (HAPG) are reported, that can yield continuous electric power from fluctuations in the ambient humidity. It is composed of polyvinyl alcohol (PVA)-wrapped highly aligned dopamine (DA)/polyvinylidene fluoride (PVDF) shell/core nanofibers (PVA@DA/PVDF NFs). As-received PVA@DA/PVDF NFs can exchange water with the ambient humidity to perform expansion and contraction and convert them into electric power. An all-fiber-based portable HAPG is fabricated and tested on human palm skin. The devices show high sensitivity and accuracy for converting the mental sweating-derived continuous moisture fluctuations into electric power. This electric power can be stored in capacitors, which is expected to power micro- and nano-electronic devices or be used in electrotherapy such as electrical stimulation to promote wound healing. Beyond this, the obtained voltage profiles exhibit unique features that can reflect the typical sweat damping oscillation curve features.


Asunto(s)
Nanofibras , Dopamina , Humanos , Alcohol Polivinílico , Polivinilos
9.
Zhen Ci Yan Jiu ; 46(6): 474-9, 2021 Jun 25.
Artículo en Chino | MEDLINE | ID: mdl-34190450

RESUMEN

In learning and evaluation of acupuncture manipulations, there are lack of quantitative physical parameters on exertion strength, duration and direction of acupuncture technique at present. Based on the tactile parameters collected during "twirling" and "lifting-thrusting" of needling, a kind of array polyvinylidene fluoride (PVDF) tactile sensor was designed. Followed by, a window segmentation method for tactile signal was proposed and the time domain features of the window were extracted. Finally, an identification method of acupuncture manipulation based on FCM (Fuzzy C-Means) was constructed. Through the experiment, it was proved that this sensor can effectively identify the four kinds of basic acupuncture manipulations, i.e. reinforcing by twirling and rotating, reducing by twirling and rotating, reinforcing by lifting and thrusting and reducing by lifting and thrusting and it was conductive to the quantification and dissemination of acupuncture manipulations.


Asunto(s)
Puntos de Acupuntura , Terapia por Acupuntura , Arterias , Aprendizaje Automático , Polivinilos
10.
J Pharm Pharmacol ; 73(7): 928-936, 2021 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-33749786

RESUMEN

OBJECTIVES: Current treatment for autonomic dysreflexia (AD) involves rupturing a liquid-filled soft capsule of nifedipine to aid rapid drug release and absorption, however, this application is not covered under the manufacturer's license. The objective of the current work was to design a rapidly dissolving solid dosage formulation for the treatment of AD as an alternative to the off-license "bite and swallow" use of currently available commercial products. METHODS: Amorphous solid dispersions (ASDs) of nifedipine were prepared by spray-drying using three different polymers: hydroxypropyl methyl cellulose (HPMC), polyvinyl pyrrolidone (PVP) and polyvinyl caprolactam-polyvinyl acetate-polyethylene glycol (Soluplus), at a 15% w/w drug loading and were formulated and compressed into tablets. Dissolution testing was performed in the paddle dissolution apparatus using either a monophasic or biphasic medium. KEY FINDINGS: The PVP-nifedipine ASD tablets exhibited rapid dissolution, with 35% of the total nifedipine dose dissolving within 15 min in the monophasic dissolution medium. The HPMC-nifedipine ASD exhibited a very slow dissolution, while the Solupus-nifedipine system exhibited no nifedipine release over 120 min. When tested in the biphasic dissolution medium, the PVP-nifedipine ASD tablets exhibited a release profile comparable to that of the pre-split/ruptured nifedipine soft capsule product. CONCLUSIONS: This study demonstrates that a nifedipine-PVP ASD is a promising formulation strategy in the treatment of AD.


Asunto(s)
Disreflexia Autónoma/tratamiento farmacológico , Composición de Medicamentos/métodos , Liberación de Fármacos , Nifedipino/farmacología , Solubilidad , Bloqueadores de los Canales de Calcio/farmacología , Técnicas de Química Sintética/métodos , Excipientes/farmacología , Humanos , Derivados de la Hipromelosa/farmacología , Polietilenglicoles/farmacología , Polivinilos/farmacología , Pirrolidinas/farmacología , Secado por Pulverización
11.
ACS Appl Mater Interfaces ; 13(9): 11320-11331, 2021 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-33625835

RESUMEN

As industrialization has spread all around the world, the problems of water pollution such as offshore oil spill and industrial sewage discharge have spread with it. Although many new separation materials have been successfully developed to deal with this crisis, a large number of water treatment materials only focus on the treatment of classified single water pollutant under mild conditions. It is a great challenge to treat soluble contaminants such as water-soluble dyes and insoluble contaminants, for example, emulsified oils simultaneously in a strong corrosive environment. Herein, in this work, corrosive resistance and multifunctional surface on a commercial polyvinylidene difluoride (PVDF) membrane via a tunicate-inspired gallic acid-assisted accurate-deposition strategy is created. Owing to the titanium-carboxylic coordination bonding and accurate-deposition strategy, the as-prepared membrane exhibits extraordinary stability, facing various harsh environmental challenges and incredibly corrosive situations (e.g., 4 M NaOH, 4 M HCl, and saturated NaCl solution). The robust multifunctional surface also endows commercial PVDF membrane with the ability for in situ separation and adsorption of surfactant-stabilized oil-in-water (corrosive and dyed) emulsions with high adsorption efficiencies up to 99.9%, separation efficiencies above 99.6%, and permeation flux as high as 15,698 ± 211 L/(m2·h·bar). Furthermore, the resultant membrane can be regenerated facilely and rapidly by flushing a small amount of HCl (4 M) or NaOH (4 M), making the corrosive resistance membrane attain a long-term and high-efficiency application for complex dyed wastewater treatment. Therefore, the multifunctional membrane has a broad application prospect in the industrial field.


Asunto(s)
Arcilla/química , Membranas Artificiales , Nanotubos/química , Polivinilos/química , Titanio/química , Purificación del Agua/instrumentación , Adsorción , Colorantes/química , Colorantes/aislamiento & purificación , Ácido Gálico/química , Interacciones Hidrofóbicas e Hidrofílicas , Polietileneimina/química , Purificación del Agua/métodos , Humectabilidad
12.
Food Microbiol ; 96: 103725, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33494898

RESUMEN

Food packaging films were coated with polyvinyl acetate (PVA) containing different concentrations of citral or Litsea (L.) cubeba essential oil (EO). Antimicrobial contact trials in style of ISO22916 were performed. Citral coatings achieved bactericidal effects against Escherichia coli (2.1 log) and Staphylococcus aureus (4.3 log) at concentrations of 20%DM. L. cubeba inactivated more than 4 log cycles of both bacteria at a concentration of 20%DM. To determine the antimicrobial activity across the gas phase, a unique method for volatile agents was developed, adapting ISO22196. GC/MS measurements were performed to supplement microbiological tests in a model packaging system with a defined 220 ml headspace (HS). HS-equilibrium concentrations of 1.8 µg/mlAir were found for 20%DM 'citral-coatings, resulting in antimicrobial effects of 3.8 log against of E. coli. Saccharomyces cerevisiae (4.74 log) and Aspergillus niger (4.29 log) were more effectively inactivated by 3%DM and 5%DM coatings. In an application trial with strawberries, simulating a headspace packaging, growth inhibitory effects on the yeast and mold microbiota were found for the 20%DM coatings.


Asunto(s)
Monoterpenos Acíclicos/farmacología , Antibacterianos/farmacología , Litsea/química , Aceites Volátiles/farmacología , Aceites de Plantas/farmacología , Monoterpenos Acíclicos/química , Antibacterianos/química , Escherichia coli/efectos de los fármacos , Escherichia coli/crecimiento & desarrollo , Embalaje de Alimentos/instrumentación , Frutas/química , Pruebas de Sensibilidad Microbiana , Aceites Volátiles/química , Aceites de Plantas/química , Polivinilos/química , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/crecimiento & desarrollo
13.
Carbohydr Polym ; 254: 117411, 2021 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-33357897

RESUMEN

Nanofibrillated cellulose films have garnered attention due to their interesting proprieties such as transparency and high mechanical strength. However, they are brittle, very hydrophilic, which is decreasing their potential applications. We have successfully achieved a simple and effective chemical modification based on polymer grafting and through plasticizer additions to increase the performance of the films as well as to improve the compatibility within conventional polymer. A preliminary study shows the possibility of using this film as an interlayer in safety glazing and/or bulletproof glass with polyvinyl butyral (PVB). The modified NFC films displays high optical transmittance (93 %), increases tensile stretch and is more hydrophobic (83°). A higher flexibility was also achieved, as the film was greatly stretched and bended without cracking or breaking. The NFC / PVB composite has three times more elongation at break, 13 % more specific energy absorbed with a half-tensile stress compared to an interlayer of PVB.


Asunto(s)
Celulosa/química , Nanofibras/química , Petróleo , Plastificantes/química , Docilidad , Polivinilos/química , Vidrio/química , Interacciones Hidrofóbicas e Hidrofílicas , Resistencia a la Tracción , Agua/química
14.
Int J Biol Macromol ; 164: 3403-3410, 2020 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-32858107

RESUMEN

Blends of chitosan (CS) and polyvinylpyrrolidone (PVP) with cobalt ferrite nanoparticles (CoFe2O4) have the potential for use in several biomedical applications as drug delivery systems and for hyperthermia applications. Herein, we present a detailed study of the effect of chitosan and PVP on the structural, magnetic and specific absorption rate (SAR) properties of CoxFe3-xO4 (x = 0.25, 0.50, 0.75 and 1.00) as an effective heat nanomediator for hyperthermia. Structural characterization was carried out using X-ray diffraction (XRD), infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Magnetic properties as a function of the Co2+ content were studied using a vibrating sample magnetometer (VSM) at room temperature. Hyperthermia investigations were performed at 454 ±â€¯20 kHz with a magnetic field amplitude of 5.5 mT. CS-PVP coated nanoparticles at x = 1.00 show a maximum SAR of 386 W/g, while bare nanoparticles show a SAR of 270 W/g. The advantage of the designed nanoparticles coated system lies in the fact that the versatile blending of chitosan and PVP enhance the SAR properties for hyperthermia of cobalt ferrite nanoparticles and provide biocompatibility and stability to the samples.


Asunto(s)
Quitosano/química , Hipertermia Inducida , Nanopartículas Magnéticas de Óxido de Hierro/química , Polivinilos/química , Pirrolidinas/química , Adsorción , Fenómenos Químicos , Técnicas de Química Sintética , Hipertermia Inducida/métodos , Nanopartículas Magnéticas de Óxido de Hierro/ultraestructura , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
15.
Drug Des Devel Ther ; 14: 2959-2975, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32801637

RESUMEN

BACKGROUND AND PURPOSE: The traditional Chinese medicine, diosgenin (Dio), has attracted increasing attention because it possesses various therapeutic effects, including anti-tumor, anti-infective and anti-allergic properties. However, the commercial application of Dio is limited by its extremely low aqueous solubility and inferior bioavailability in vivo. Soluplus, a novel excipient, has great solubilization and capacity of crystallization inhibition. The purpose of this study was to prepare Soluplus-mediated Dio amorphous solid dispersions (ASDs) to improve its solubility, bioavailability and stability. METHODS: The crystallization inhibition studies were firstly carried out to select excipients using a solvent shift method. According to solubility and dissolution results, the preparation methods and the ratios of drug to excipient were further optimized. The interaction between Dio and Soluplus was characterized by differential scanning calorimetry (DSC), fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and molecular docking. The pharmacokinetic study was conducted to explore the potential of Dio ASDs for oral administration. Furthermore, the long-term stability of Dio ASDs was also investigated. RESULTS: Soluplus was preliminarily selected from various excipients because of its potential to improve solubility and stability. The optimized ASDs significantly improved the aqueous solubility of Dio due to its amorphization and the molecular interactions between Dio and Soluplus, as evidenced by dissolution test in vitro, DSC, FT-IR spectroscopy, SEM, PXRD and molecular docking technique. Furthermore, pharmacokinetic studies in rats revealed that the bioavailability of Dio from ASDs was improved about 5 times. In addition, Dio ASDs were stable when stored at 40°C and 75% humidity for 6 months. CONCLUSION: These results indicated that Dio ASDs, with its high solubility, high bioavailability and high stability, would open a promising way in pharmaceutical applications.


Asunto(s)
Diosgenina/farmacocinética , Desarrollo de Medicamentos , Medicamentos Herbarios Chinos/farmacocinética , Excipientes/farmacocinética , Polietilenglicoles/farmacocinética , Polivinilos/farmacocinética , Administración Oral , Animales , Disponibilidad Biológica , Cromatografía Líquida de Alta Presión , Cristalografía por Rayos X , Diosgenina/administración & dosificación , Composición de Medicamentos , Estabilidad de Medicamentos , Medicamentos Herbarios Chinos/administración & dosificación , Excipientes/administración & dosificación , Masculino , Medicina Tradicional China , Conformación Molecular , Simulación del Acoplamiento Molecular , Polietilenglicoles/administración & dosificación , Polivinilos/administración & dosificación , Ratas , Ratas Sprague-Dawley , Solubilidad , Espectrometría de Masas en Tándem
16.
J Chromatogr A ; 1626: 461349, 2020 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-32797829

RESUMEN

In the present work, a very sensitive and fully automated direct immersion PAL SPME Arrow procedure, coupled with GC-MS, has been developed and validated for determination of nine phosphorus flame retardants in different types of water samples (river, drinking and rainwater). PDMS/DVB was selected among three commercially available SPME Arrows (PDMS/DVB, DVB/PDMS/CWR and PDMS/CWR), since it resulted in the best sensitivity. The important experimental parameters were optimized via a central composite design response surface methodology and as result, extraction time of 65 min, extraction temperature of 80 °C and added salt concentration of 19% (w/v), were selected as the optimum values. The optimized method showed linear response over the calibration range (2 - 500 ng L-1), with R2-values higher than 0.9937. The precision (RSD%) measured by replicate analyses (n = 7) was estimated at 2 and 100 ng L-1 and was less than 29% and 21%, respectively. The LOQ of PAL SPME Arrow, calculated as S/N = 10, was between 0.2 and 1.2 ng L-1 (for triphenyl phosphate and tris-(1­chloro­2-propyl) phosphate, respectively) with extraction efficiencies between 5.9 and 31% (for tris-(1,3-dichloro-2-propyl) phosphate and tri-n­butyl phosphate, respectively). To assess the performance of the developed technique for real samples, two river water samples, tap water from two regions and a rainwater sample were analyzed. Most of the target analytes were observed in the river samples with concentrations of 1.0 - 250 ng L-1 and the obtained recoveries at 50 ng L-1 ranged between 60 and 107%. Considering the figures of merit of the optimized method, PAL SPME Arrow-GC-MS showed to be the most sensitive analytical approach for determination of phosphorus flame retardants in water, with satisfying precision and accuracy, compared with conventional SPME-NPD, LLE-GC-MS and SPE-LC-MS/MS.


Asunto(s)
Retardadores de Llama/análisis , Fósforo/análisis , Microextracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/análisis , Automatización , Dimetilpolisiloxanos/química , Cromatografía de Gases y Espectrometría de Masas , Polivinilos/química , Soluciones
17.
Drug Dev Ind Pharm ; 46(8): 1219-1229, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32643446

RESUMEN

OBJECTIVE: The main objective of this work was to formulate a nanodispersion containing grape seed extract and analyzed its release profile, antioxidant potential of the prepared formulations. METHODS: The grape seed extract (GSE) containing proanthocyanidins (PC's) has been dispersed in polymer matrix soluplus (SOLU) by the freeze-drying method. The morphological analysis was carried out using atomic force microscopy (AFM), scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The in-vitro release of the nanodispersion formulations was evaluated by simulated intestinal fluid (SIF). The antioxidant activity of GSE and the formulation were evaluated by employing various in-vitro assays such as 2, 2'-azino-bis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), 2, 2-diphenyl-1- picrylhydrazyl (DPPH), Ferric reducing antioxidant power (FRAP) and peroxidation inhibiting activity. RESULTS: The formulation FIII (1:5) resulted in a stable formulation with a higher loading efficiency of 95.36%, a particle size of 69.90 nm, a polydispersity index of 0.154 and a zeta potential value of -82.10 mV. The antioxidant efficiency of GSE-SOLU evaluated by DPPH was found to be 96.7%. The ABTS and FRAP model exhibited a dose-dependent scavenging activity. Linoleic model of FIII formulation and GSE exhibited a 66.14 and 86.58% inhibition respectively at 200 µg/l. CONCLUSIONS: The main reason for excellent scavenging activity of the formulations can be attributed to the presence of monomeric, dimeric, oligomeric procyanidins and the phenolic group. The present work denotes that GSE constitutes a good source of PC's and will be useful in the prevention and treatment of free radical related diseases.


Asunto(s)
Antioxidantes/farmacología , Extracto de Semillas de Uva/farmacología , Polietilenglicoles/farmacología , Polivinilos/farmacología , Extracto de Semillas de Uva/química , Polietilenglicoles/química , Polivinilos/química
18.
J Mater Chem B ; 8(32): 7121-7134, 2020 08 19.
Artículo en Inglés | MEDLINE | ID: mdl-32648878

RESUMEN

The Prussian blue (PB) based nanostructure is a mixed-valence coordination network with excellent biosafety, remarkable photothermal effect and multiple enzyme-mimicking behaviours. Compared with other nanomaterials, PB-based nanoparticles (NPs) exhibit several unparalleled advantages in biomedical applications. This review begins with the chemical composition and physicochemical properties of PB-based NPs. The tuning strategies of PB-based NPs and their biomedical properties are systemically demonstrated. Afterwards, the biomedical applications of PB-based NPs are comprehensively recounted, mainly focusing on treatment of tumors, bacterial infection and inflammatory diseases. Finally, the challenges and future prospects of PB-based NPs and their application in disease treatment are discussed.


Asunto(s)
Antibacterianos/química , Antiinflamatorios/química , Antineoplásicos/química , Materiales Biocompatibles/química , Ferrocianuros/química , Nanopartículas del Metal/química , Animales , Antibacterianos/farmacología , Antiinflamatorios/farmacología , Antineoplásicos/farmacología , Materiales Biocompatibles/farmacología , Ferrocianuros/farmacología , Humanos , Imagen por Resonancia Magnética , Imagen Multimodal , Nanocompuestos/química , Imagen Óptica , Fototerapia , Polilisina/química , Polivinilos/química , Porosidad , Pirrolidinas/química , Nanomedicina Teranóstica
19.
Chemosphere ; 259: 127440, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32590178

RESUMEN

A new mixed matrix membrane (MMM) was prepared by incorporating biological mesoporous carbon microspheres (mCMSs) from corn starch polysaccharide-supported hydrophilic polydopamine (PDA), as a mesoporous and large-surface area filler, selective modifier, and pore-forming agent, into polyvinylidene fluoride (PVDF) matrix in presence of polyethylene glycol (PEG) as a hydrophilic agent. The structural parameters of the prepared membranes were characterized via FE-SEM, BET/BJH, XRD, FT-IR, and AFM analyses, sorption experiments, water permeability assessments, porosimetry tests, flux recovery ratio (FRR) evaluations, and contact angle measurements, with the so-called central composite design (CCD) been successfully applied for optimization and investigation of the effects of the operational parameters. The results were then applied to treat double-distilled water containing bovine serum albumin (BSA) utilizing a cross-module set-up. Based on the findings, the content of the mCMS-PDA in the PVDF matrix significantly affected the contact angle, pure water flux (PWF), FRR, and BSA removal. In this respect, the PWF of the PVDF-PEG-mCMS-PDA increased from 10.25 to 27.78 L/m2 h with increasing the mCMS-PDA content, with the peak FRR (93.84%) of the PVDF-PEG-mCMS-PDA seen at maximum surface hydrophilicity of the membrane.


Asunto(s)
Carbono/química , Membranas Artificiales , Albúmina Sérica Bovina/química , Purificación del Agua/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Indoles , Microesferas , Permeabilidad , Polímeros , Polivinilos , Espectroscopía Infrarroja por Transformada de Fourier , Agua/química , Zea mays
20.
Drug Deliv ; 27(1): 565-574, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32252563

RESUMEN

Hinokiflavone (HF) is a natural biflavonoid extracted from medicinal plants such as Selaginella tamariscina and Platycladus orientalis. HF plays a crucial role in the treatment of several cancers. However, its poor solubility, instability, and low bioavailability have limited its use. In this study, soluplus/d-α-tocopherol acid polyethylene glycol 1000 succinate (TPGS)/dequalinium (DQA) was applied to improve the solubilization efficiency and stability of HF. HF hybrid micelles were prepared via thin-film hydration method. The physicochemical properties of micelles, including particle size, zeta potential, encapsulation efficiency, drug loading, CMC value, and stability were investigated. The in vitro cytotoxicity assay showed that the cytotoxicity of the HF hybrid micelles was higher than that of free HF. In addition, the HF hybrid micelles improved anticancer efficacy and induced mitochondria-mediated apoptosis, which is associated with the high levels of ROS inducing decreased mitochondrial membrane potential, promoting apoptosis of tumor cells. Furthermore, in vivo tumor suppression, smaller tumor volume and increased expression of pro-apoptotic proteins were found in nude mice treated with HF hybrid micelles, suggesting that HF hybrid micelles had stronger tumor suppressive activity compared with free HF. In summary, HF hybrid micelles developed in this study enhanced antitumor effect, which may be a potential drug delivery system for the treatment of lung adenocarcinoma.


Asunto(s)
Adenocarcinoma del Pulmón/tratamiento farmacológico , Antineoplásicos/administración & dosificación , Biflavonoides/administración & dosificación , Portadores de Fármacos/administración & dosificación , Neoplasias Pulmonares/tratamiento farmacológico , Micelas , Mitocondrias/efectos de los fármacos , Células A549 , Animales , Antineoplásicos/farmacocinética , Antineoplásicos/farmacología , Biflavonoides/farmacocinética , Biflavonoides/farmacología , Decualinio/administración & dosificación , Decualinio/química , Decualinio/farmacocinética , Portadores de Fármacos/química , Portadores de Fármacos/farmacocinética , Femenino , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Tamaño de la Partícula , Polietilenglicoles/administración & dosificación , Polietilenglicoles/química , Polietilenglicoles/farmacocinética , Polivinilos/administración & dosificación , Polivinilos/química , Polivinilos/farmacocinética , Solubilidad , Ensayos Antitumor por Modelo de Xenoinjerto , alfa-Tocoferol/administración & dosificación , alfa-Tocoferol/análogos & derivados , alfa-Tocoferol/química , alfa-Tocoferol/farmacocinética
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