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1.
Small ; : e2404297, 2024 Sep 16.
Artículo en Inglés | MEDLINE | ID: mdl-39282822

RESUMEN

Polymer solid-state electrolytes offer great promise for battery materials with high energy density, mechanical stability, and improved safety. However, their low ion conductivities have so far limited their potential applications. Here, it is shown for poly(ethylene oxide) block copolymers that the super-stoichiometric addition of lithium bis(trifluoromethanesulfonyl) imide (LiTFSI) as lithium salt leads to the formation of a crystalline PEO block copolymer phase with exceptionally high ion conductivities and low activation energies. The addition of LiTFSI further induces block copolymer phase transitions into bi-continuous Fddd and gyroid network morphologies, providing continuous 3D conduction pathways. Both effects lead to solid-state block copolymer electrolyte membranes with ion conductivities of up to 1·10-1 S cm-1 at 90 °C, decreasing only moderately to 4·10-2 S cm-1 at room temperature, and to >1·10-3 S cm-1 at -20 °C, corresponding to activation energies as low as 0.19 eV. The co-crystallization of PEO and LiTFSI with ether and carbonate solvents is observed to play a key role to realize a super-ionic conduction mechanism. The discovery of PEO super-ionic conductivity at high lithium concentrations opens a new pathway for fabrication of solid polymer electrolyte membranes with sufficiently high ion conductivities over a broad temperature range with widespread applications in electrical devices.

2.
Small ; 20(4): e2305772, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37712152

RESUMEN

The limited ionic conductivity at room temperature and the constrained electrochemical window of poly(ethylene oxide) (PEO) pose significant obstacles that hinder its broader utilization in high-energy-density lithium metal batteries. The garnet-type material Li6.4 La3 Zr1.4 Ta0.6 O12 (LLZTO) is recognized as a highly promising active filler for enhancing the performance of PEO-based solid polymer electrolytes (SPEs). However, its performance is still limited by its high interfacial resistance. In this study, a novel hybrid filler-designed SPE is employed to achieve excellent electrochemical performance for both the lithium metal anode and the LiFePO4 cathode. The solid composite membrane containing hybrid fillers achieves a maximum ionic conductivity of 1.9 × 10-4 S cm-1 and a Li+ transference number of 0.67 at 40 °C, respectively. Additionally, the Li/Li symmetric cells demonstrate a smooth and stable process for 2000 h at a current density of 0.1 mA cm-2 . Furthermore, the LiFePO4 /Li battery delivers a high-rate capacity of 159.2 mAh g-1 at 1 C, along with a capacity retention of 95.2% after 400 cycles. These results validate that employing a composite of both active and inactive fillers is an effective strategy for achieving superior performance in all-solid-state lithium metal batteries (ASSLMBs).

3.
Chem Rec ; 24(2): e202300166, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37387571

RESUMEN

This review aims to provide a literature overview as well as the authors' personal account to the studies of Laponite® (Lap)/Polyethylene-oxide (PEO) based composite materials and their applications. These composites can be prepared over a wide range of their mutual concentrations, they are highly water soluble, and have many useful physico-chemical properties. To the readers' convenience, the contents are subdivided into different sections, related with consideration of PEO properties and its solubility in water, behavior of Lap systems(structure of Lap-platelets, properties of aqueous dispersions of Lap and aging effects in them), analyzing ofproperties LAP/PEO systems, Lap platelets-PEO interactions, adsorption mechanisms, aging effects, aggregation and electrokinetic properties. The different applications of Lap/PEO composites are reviewed. These applications include Lap/PEO based electrolytes for lithium polymer batteries, electrospun nanofibers, environmental, biomedical and biotechnology engineering. Both Lap and PEO are highly biocompatible with living systems and they are non-toxic, non-yellowing, and non-inflammable. Medical applications of Lap/PEO composites in bio-sensing, tissue engineering, drug delivery, cell proliferation, and wound dressings are also discussed.

4.
Angew Chem Int Ed Engl ; 63(44): e202410347, 2024 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-39091135

RESUMEN

Polyethylene oxide (PEO)-based all-solid-state lithium metal batteries (ASSLMBs) are strongly hindered by the fast dendrite growth at the Li metal/electrolyte interface, especially under large rates. The above issue stems from the suboptimal interfacial chemistry and poor Li+ transport kinetics during cycling. Herein, a SnF2-catalyzed lithiophilic-lithiophobic gradient solid electrolyte interphase (SCG-SEI) of LixSny/LiF-Li2O is in situ formed. The superior ionic LiF-Li2O rich upper layer (17.1 nm) possesses high interfacial energy and fast Li+ diffusion channels, wherein lithiophilic LixSny alloy layer (8.4 nm) could highly reduce the nucleation overpotential with lower diffusion barrier and promote rapid electron transportation for reversible Li+ plating/stripping. Simultaneously, the insoluble SnF2-coordinated PEO promotes the rapid Li+ ion transport in the bulk phase. As a result, an over 46.7 and 3.5 times improvements for lifespan and critical current density of symmetrical cells are achieved, respectively. Furthermore, LiFePO4-based ASSLMBs deliver a recorded cycling performance at 5 C (over 1000 cycles with a capacity retention of 80.0 %). More importantly, impressive electrochemical performances and safety tests with LiNi0.8Mn0.1Co0.1O2 and pouch cell with LiFePO4, even under extreme conditions (i.e., 100 °C), are also demonstrated, reconfirmed the importance of lithiophilic-lithiophobic gradient interfacial chemistry in the design of high-rate ASSLMBs for safety applications.

5.
Angew Chem Int Ed Engl ; 63(13): e202317256, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38289336

RESUMEN

Powdery hexagonal boron nitride (h-BN), as an important material for electrochemical energy storage, has been typically synthesized in bulk and one/two-dimensional (1/2D) nanostructured morphologies. However, until now, no method has been developed to synthesize powdery three-dimensional (3D) h-BN. This work introduces a novel NaCl-glucose-assisted strategy to synthesize micron-sized 3D h-BN with a honeycomb-like structure and its proposed formation mechanism. We propose that NaCl acts as the template of 3D structure and promotes the nitridation reaction by adsorbing NH3 . Glucose facilitates the homogeneous coating of boric acid onto the NaCl surface via functionalizing the NaCl surface. During the nitridation reaction, boron oxides (BO4 and BO3 ) form from a dehydration reaction of boric acid, which is then reduced to O2 -B-N and O-B-N2 intermediates before finally being reduced to BN3 by NH3 . When incorporated into polyethylene oxide-based electrolytes for Li metal batteries, 5 wt % of 3D h-BN significantly enhances ionic conductivity and mechanical strength. Consequently, this composite electrolyte demonstrates superior electrochemical stability. It delivers 300 h of stable cycles in the Li//Li cell at 0.1 mA cm-2 and retains 89 % of discharge capacity (138.9 mAh g-1 ) after 100 cycles at 1 C in the LFP//Li full cell.

6.
Chemistry ; 29(24): e202204035, 2023 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-36750402

RESUMEN

Polyethylene oxide (PEO)-based polymer electrolytes with good flexibility and viscoelasticity, low interfacial resistance, and fabricating cost have caught worldwide attention, but their practical application is still hampered by the instability at high voltages and the low ionic conductivity (10-8 to 10-6  S cm-1 ). Herein, we rationally designed defects-abundant Ga2 O3 nanobricks as multifunctional fillers and constructed a PEO-based organic-inorganic electrolyte for lithium metal batteries. Due to the abundant O-defects feature of Ga2 O3 filler, this PEO-based composite electrolyte not only broadens electrochemical stability window (over 5.3 V versus Li/Li+ ) but also in situ forms a Li-Ga alloy and solid electrolyte interphase (SEI) film during the cycling process causing a rapid diffusion of Li+ ions. The as-prepared electrolyte has good interface compatibility with Li metal (without short-circuiting over 500 h at 0.2 mA cm-2 ) and possesses superior high ionic conductivity. The assembled all-solid-state LiFePO4 //Li cells attained an excellent cycling performance of 146 mAh g-1 over 100 cycles at 0.5 C. The XPS analysis reveals that Ga2 O3 nanobricks can form in situ a Li-Ga alloy layer at the polymer/anode interface. This work shed a light on designing high ionic conductivity lithium alloys in the composite electrolyte, which can improve the electrochemical properties of PEO-based polymer electrolytes.

7.
J Food Sci Technol ; 60(11): 2881-2892, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37711579

RESUMEN

The aim of this research was to compare the effects of various solvents on producing kafirin/polyethylene oxide (PEO) bio-nanocomposites by the technique of electrospinning. Different concentrations of kafirin (15, 20, 25, 30 and 40% w/v) and PEO (2, 4 and 6% w/v) were electrospun. For the dissolution and electrospinning of these two biopolymers, different solvents were used comparatively, i.e. distilled water, ethanol (70%), acetic acid (40%), 2-Butanol and glacial acetic acid. An evaluation of flow behavior showed that kafirin and PEO had Newtonian and pseudoplastic behaviors, respectively. A mixture of these two polymers demonstrated quasi-Newtonian and shear-independent behaviors in a low shear rate range, which positively affected the electrospinning process. SEM images showed that the best concentrations of kafirin and PEO were 25 and 2%, respectively, for producing nanofibers with uniform structures. Fourier-transform infrared spectroscopy (FTIR) indicated the presence of kafirin and PEO in the bio-nanocomposite after electrospinning. The FTIR proved that these two polymers had no chemical interactions with each other. Overall, the results showed that selecting an appropriate solvent and a suitable auxiliary polymer could have significant roles in producing biodegradable kafirin nanofibers.

8.
Int J Mol Sci ; 23(2)2022 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-35055172

RESUMEN

Reduced graphene oxide (rGO) is one of the graphene derivatives that can be employed to engineer bioactive and/or electroactive scaffolds. However, the influence of its low and especially high concentrations on scaffolds' overall properties and cytotoxicity has yet to be explored. In this study, polyethylene oxide (PEO)-based scaffolds containing from 0.1 to 20 wt% rGO were obtained by electrospinning. Morphological, thermal and electrical properties of the scaffolds were characterized by SEM, Raman spectroscopy, XRD, DSC and electrical measurements. The diameter of the fibers decreased from 0.52 to 0.19 µm as the concentration of rGO increased from 0.1 wt% to 20 wt%. The presence of rGO above the percolation threshold (5.7 wt%) resulted in a significantly reduced electrical resistivity of the scaffolds. XRD and Raman analysis revealed delamination of the graphene layers (interlayer spacing increased from 0.36 nm to 0.40-0.41 nm), and exfoliation of rGO was detected for the samples with an rGO concentration lower than 1 wt%. In addition, an evident trend of increasing cell viability as a function of the rGO concentration was evidenced. The obtained results can serve as further guidance for the judicious selection of the rGO content incorporated into the PEO matrix for constructing electroactive scaffolds.


Asunto(s)
Grafito/química , Polietilenglicoles/química , Andamios del Tejido/química , Línea Celular , Supervivencia Celular , Humanos , Espectrometría Raman , Ingeniería de Tejidos , Difracción de Rayos X
9.
Molecules ; 27(19)2022 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-36235290

RESUMEN

Ceramic/polymer composite solid electrolytes integrate the high ionic conductivity of in ceramics and the flexibility of organic polymers. In practice, ceramic/polymer composite solid electrolytes are generally made into thin films rather than sintered into bulk due to processing temperature limitations. In this work, Li6.4La3Zr1.4Ta0.6O12 (LLZTO)/polyethylene-oxide (PEO) electrolyte containing bis(trifluoromethanesulfonyl)imide (LiTFSI) as the lithium salt was successfully fabricated into bulk pellets via the cold sintering process (CSP). Using CSP, above 80% dense composite electrolyte pellets were obtained, and a high Li-ion conductivity of 2.4 × 10-4 S cm-1 was achieved at room temperature. This work focuses on the conductivity contributions and microstructural development within the CSP process of composite solid electrolytes. Cold sintering provides an approach for bridging the gap in processing temperatures of ceramics and polymers, thereby enabling high-performance composites for electrochemical systems.

10.
AAPS PharmSciTech ; 23(7): 265, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-36163600

RESUMEN

Pharmaceutical opioid dosage forms are commonly misused via an oral route in non-manipulated form, i.e., overdose in intact form, or manipulated form, i.e., after crushing the dosage form, and also via the non-oral route in manipulated form, particularly the parenteral or nasal route. To assess the self-regulated anti-overdose property, crushing strength, extractability, and syringeability of the developed drug delivery system by in vitro laboratory studies. Tapentadol HCl drug particulates fabricated using different polymers were assessed for extractability studies in 25 ml of water at room temperature (RT) and at > 90°C. Crushing strength was assessed by grinding the drug particulates in a mortar and pestle and a coffee grinder for 1 min. For syringeability, an attempt was made to withdraw the drug mixture using a 1 ml insulin syringe for 1 min. To assess the self-regulated anti-overdose property, in vitro dissolution testing on a single-capsule per dissolution vessel (normal condition) and four-capsules per dissolution vessel (overdose condition) was performed. POLYOX, Natrosol, and Blanose-containing drug particles retarded drug extraction by > 80% at RT and > 90°C. After 1 min of grinding in a mortar and pestle and a coffee grinder, crushed POLYOX-containing drug particulates were retained at > 99% on the ASTM-170# screen. The attempt to withdraw the viscous mixture of drug formulation prepared with 5 ml of water for 1 min using a 1 ml insulin syringe was unsuccessful. In dissolution studies, more than 90% of the drug was released in normal conditions, and more than 90% of the drug was retarded in overdose conditions. In vitro laboratory studies demonstrate that the developed self-regulated anti-overdose crush-resistant drug delivery system may deter misuse via oral and non-oral routes.


Asunto(s)
Sobredosis de Droga , Insulinas , Sobredosis de Opiáceos , Analgésicos Opioides , Café , Preparaciones de Acción Retardada , Composición de Medicamentos , Sistemas de Liberación de Medicamentos , Humanos , Polímeros , Tapentadol , Agua
11.
Small ; 17(39): e2102978, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34416079

RESUMEN

Solid composite electrolyte-based Li battery is viewed as one of the most competitive system for the next generation batteries; however, it is still restricted by sluggish ion diffusion. Fast ion transport is a characteristic of the polyethylene oxide (PEO) amorphous phase, and the mobility of Li+ is restrained by the coordination interaction within PEO and Li+ . Herein, the design of applying functionalized carbon dots (CDs) with abundant surface features as fillers is proposed. High ionic conductivity is achieved in the CD-based composite electrolytes resulting from enhanced ion migration ability of polymer segments and mobility of Li+ . Specially, the optimum effect with nitrogen and sulfur co-doped carbon dots (NS-CD) is a consequence of strong interaction between edge-nitrogen/sulfur in NS-CD and Li+ . Solid-state nuclear magnetic resonance results confirm that more mobile Li+ is generated. Moreover, it is observed that lithium dendrite is suppressed compared to PEO electrolyte associated with reinforced mechanical properties and high transference number. The corresponding all-solid-state batteries, with the cathode of LiFePO4 or high voltage NCM523, exhibit long cycling life and excellent rate performances. It is a novel strategy to achieve high ionic conductivity composite electrolyte with uniform lithium deposition and provides a new direction to the mechanism of fast Li+ movement.

12.
Pharm Res ; 38(7): 1263-1278, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34128146

RESUMEN

A method to reproducibly mill abuse deterrent oxycodone hydrochloride (HCl) extended release (ER) tablets was developed for a nasal insufflation pharmacokinetic (PK) study. Several comminution methods were explored before determining that a conical mill resulted in controlled milling of tablets to a size range equal to or below 1000 µm. However, milling resulted in significant loss of oxycodone from abuse deterrent oxycodone HCl ER tablets compared to minimal oxycodone loss from oxycodone HCl immediate release (IR) tablets. Characterization of milled tablet powder showed that loss of oxycodone was not attributed to analytical procedures or oxycodone phase change during high intensity milling processes. The content uniformity of oxycodone in the milled tablet powder varied when ER and IR tablets were milled to a particle size distribution equal to or below 500 µm but did not vary when particles were sized above 500 µm to equal to or below 1000 µm. In addition, the initial excipient weight to drug substance weight ratio impacted the amount of oxycodone lost from the respective formulation. However, dissolution demonstrated that when oxycodone HCl ER tablets are milled, differences in excipient weight to drug substance weight ratio and particle size distribution of milled tablets did not result in significantly different release of oxycodone.


Asunto(s)
Formulaciones Disuasorias del Abuso , Analgésicos Opioides/química , Composición de Medicamentos/métodos , Dependencia de Morfina/prevención & control , Oxicodona/química , Analgésicos Opioides/administración & dosificación , Analgésicos Opioides/farmacocinética , Química Farmacéutica , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/química , Preparaciones de Acción Retardada/farmacocinética , Liberación de Fármacos , Insuflación , Oxicodona/administración & dosificación , Oxicodona/farmacocinética , Polvos , Imagen Individual de Molécula , Comprimidos
13.
Int J Mol Sci ; 22(2)2021 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-33478151

RESUMEN

Mixtures of polyethylene oxide (PEO, M.W.~900,000) and imidazolium ionic liquids (ILs) are studied using high-pressure Fourier-transform infrared spectroscopy. At ambient pressure, the spectral features in the C-H stretching region reveal that PEO can disturb the local structures of the imidazolium rings of [BMIM]+ and [HMIM]+. The pressure-induced phase transition of pure 1-butyl-3-methylimidazolium bromide ([BMIM]Br) is observed at a pressure of 0.4 GPa. Pressure-enhanced [BMIM]Br-PEO interactions may assist PEO in dividing [BMIM]Br clusters to hinder the aggregation of [BMIM]Br under high pressures. The C-H absorptions of pure 1-hexyl-3-methylimidazolium bromide [HMIM]Br do not show band narrowing under high pressures, as observed for pure [BMIM]Br. The band narrowing of C-H peaks is observed at 1.5 GPa for the [HMIM]Br-PEO mixture containing 80 wt% of [HMIM]Br. The presence of PEO may reorganize [HMIM]Br clusters into a semi-crystalline network under high pressures. The differences in aggregation states for ambient-pressure phase and high-pressure phase may suggest the potential of [HMIM]Br-PEO (M.W.~900,000) for serving as optical or electronic switches.


Asunto(s)
Imidazoles/química , Líquidos Iónicos/química , Polietilenglicoles/química , Hidrocarburos Bromados/química , Estructura Molecular , Transición de Fase , Presión , Espectrofotometría Infrarroja/métodos
14.
Molecules ; 26(5)2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33668167

RESUMEN

Jussara pulp (Euterpe edulis Mart.) is rich in bioactive compounds known to be protective mediators against several diseases. In this context, nevertheless, anthocyanins, the most abundant natural pigment in jussara, are sensitive to temperature, pH, oxygen, and light conditions, leading to instability during food storage or digestion, and, thus jeopardizing the antioxidant proprieties retained by these flavonoids and limiting industrial application of the pulp. The production of nanostructures, from synthetic and natural polymers, containing natural matrices rich in bioactive compounds, has been widely studied, providing satisfactory results in the conservation and maintenance of the stability of these compounds. The current work aimed to compare uniaxial and coaxial electrospinning operation modes to produce core-shell jussara pulp nanofibers (NFs). Additionally, the parameters employed in the electrospinning processes were optimize using response surface methodology in an attempt to solve stability issues for the bioactive compounds. The best experimental conditions provided NFs with diameters ranging between 110.0 ± 47 and 121.1 ± 54 nm. Moreover, the coaxial setup improved jussara pulp NF formation, while further allowing greater integrity of NFs structures.


Asunto(s)
Antioxidantes/química , Materiales Biocompatibles/química , Euterpe/química , Nanofibras/química , Brasil , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Propiedades de Superficie
15.
Drug Dev Ind Pharm ; 46(5): 852-860, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32338551

RESUMEN

Metformin hydrochloride (MFM) is often used as a controlled-release (CR) tablet to reduce dosing frequency. However, the MFM CR tablet contains significant amounts of excipients and the tablet size is also large. Dosing convenience and patient compliance can be increased by reducing the size of the CR tablets. The aim of this study was to prepare and evaluate the MFM controlled-release tablet (MFM-CRT) using two types of release modulators, inner and outer. The MFM-CRT was prepared by coating the MFM granules using a binder solution containing aluminum stearate (ALS) as the inner release-modulator, and polyethylene oxide (PEO) as the outer release-modulator. The dispersion stability of the binder solution was optimized by the dispersion analyzer. The MFM-CRT was evaluated for dissolution rate and tablet volume. Additionally, dissolution behavior and dissolution kinetics of the MFM-CRT were analyzed using micro-computed tomography (micro-CT). Although the optimal MFM-CRT showed no difference in the release rate as compared to the commercially available product of Glucophage® XR 500 mg (f2 value: 72), the length of the long axis was reduced by 6 mm and the weight was reduced by about 27%. We expect patient compliance to improve because of effective sustained release and volume reduction of MFM-CRT.


Asunto(s)
Portadores de Fármacos/síntesis química , Liberación de Fármacos , Ácidos Grasos/síntesis química , Hipoglucemiantes/síntesis química , Metformina/síntesis química , Preparaciones de Acción Retardada/síntesis química , Preparaciones de Acción Retardada/metabolismo , Portadores de Fármacos/metabolismo , Ácidos Grasos/metabolismo , Hipoglucemiantes/metabolismo , Metformina/metabolismo , Espectrometría por Rayos X/métodos , Microtomografía por Rayos X/métodos
16.
AAPS PharmSciTech ; 21(3): 86, 2020 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-31997096

RESUMEN

The main goal of the presented work was to understand changes in the microstructure of tablets, as well as the properties of its main component viz. polyethylene oxide (PEO) as a function of sintering. Key polymer variables and sintering conditions were investigated, and sintering-induced increase in tablet tensile strength was evaluated. For the current study, binary-component placebo tablets comprised of varying ratios of PEO and anhydrous dibasic calcium phosphate (DCP) were prepared at two levels of tablet solid fraction. The prepared tablets were sintered in an oven at 80°C at different time points ranging from 10 to 900 min and were evaluated for pore size, tablet expansion (%), and PEO crystallinity. The results showed that for efficient sintering and a significant increase in the tablet tensile strength, a minimum of 50% w/w PEO was required. Moreover, all microstructural changes in tablets were found to occur within 60 min of sintering, with no significant changes occurring thereafter. Sintering also resulted in a decrease in PEO crystallinity, causing changes in polymer ductility. These changes in PEO ductility resulted in tablets with higher tensile strength. Formulation variables such as PEO level and PEO particle size distribution were found to be important influencers of the sintering process. Additionally, tablets with high initial solid fraction and sintering duration of 60 min were found to be optimal conditions for efficient sintering of PEO-based compacts. Finally, prolonged sintering times were not found to provide any additional benefits in terms of abuse-deterrent properties.


Asunto(s)
Formulaciones Disuasorias del Abuso , Polietilenglicoles/química , Comprimidos/química , Resistencia a la Tracción
17.
AAPS PharmSciTech ; 21(7): 270, 2020 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-33025237

RESUMEN

Abuse-deterrent formulations (ADFs) using physical/chemical barrier approaches limit abuse by providing resistance to dosage form manipulation to limit drug extraction or altered release. Standardizing in vitro testing methods to assess the resistance to manipulation presents a number of challenges, including the variation in particle sizes resulting from the use of various tools to alter the tablet matrix (e.g., grinding, chipping, crushing). A prototype, direct-compression ADF using a sintered polyethylene oxide (PEO) matrix containing dextromethorphan, an enantiomeric form of the opioid, levorphanol, was developed to evaluate testing methodologies for retention of abuse-deterrent properties following dosage form tampering. Sintered PEO tablets were manipulated by grinding, and drug content and release were evaluated for the recovered granules. Drug content analysis revealed that higher amounts of drug were contained in the smaller size granules (< 250 µm, 190% of the theoretical amount) compared with the larger particles (> 250 µm, 55-75% of theoretical amount). Release testing was performed on various size granule fractions (> 850 µm, 500-850 µm, 250-500 µm, and < 250 µm) using USP type I (basket), type II (paddle), and type IV (flow-through) apparatus. The USP type I and type II apparatus gave highly variable release results with poor discrimination among the release rates from different size granules. The observed sticking of the hydrated granules to the baskets and paddles, agglomeration of hydrated granules within the baskets/vessels, and ongoing PEO hydration with subsequent gel formation further altered the particle size and impacted the rate of drug release. The use of a flow-through apparatus (USP type IV) resulted in improved discrimination of drug release from different size granules with less variability due to better dispersion of granules (minimal sticking and aggregation). Drug release profiles from the USP type IV apparatus showed that the larger size granules (> 500 µm) offered continued resistance to drug release following tablet manipulation, but the smaller size granules (< 500 µm) provided rapid drug release that was unhindered by the hydrated granule matrix. Since < 500-µm size particles are preferred for nasal abuse, improved direct-compression ADF formulations should minimize the formation of these smaller-sized particles following tampering to maintain the product's abuse-deterrent features.


Asunto(s)
Liberación de Fármacos , Polietilenglicoles/química , Trastornos Relacionados con Sustancias/prevención & control , Comprimidos/química , Preparaciones de Acción Retardada/química , Composición de Medicamentos/métodos , Humanos , Tamaño de la Partícula
18.
J Cell Physiol ; 234(8): 13951-13958, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-30633333

RESUMEN

Hard tissue lesion treatment in oral and maxillofacial has been challenging because of tissue complexities. This study aimed to investigate novel biopolymeric construct effects on the osteogenic differentiation potential of the dental pulp stem cells (DPSCs) for introducing a cell copolymer bioimplant. A blended polycaprolactone (PCL)-polyethylene oxide (PEO) was fabricated using electrospinning, simultaneously filled by ß-glycerophosphate (ß-GP). After that biocompatibility and release kinetics of the PCL-PEO+ß-GP was evaluated and compared with PCL-PEO and then the osteogenic differentiation potential of the DPSCs was examined while being cultured on the scaffolds and compared with those cultured on the culture plate. The results demonstrated that scaffolds have not any cytotoxicity and ß-GP can release in a long-term manner. Alkaline phosphatase activity and calcium content were significantly increased in DPSCs while being cultured on the PCL-PEO+ß-GP compared with the other groups. Runt-related transcription factor 2, collagen type-I, osteonectin, and osteocalcin (OSC) genes expression was upregulated in DPSCs cultured on the PCL-PEO+ß-GP and was significantly higher than those cultured on the PCL-PEO. Immunocytochemistry result also confirmed the positive effects of PCL-PEO+ß-GP on the osteogenic differentiation of the DPSCs by presenting a higher OSC protein expression. According to the results, incorporation of the ß-GP in PCL-PEO makes a better construct for osteogenic induction into the stem cells and it could be also considered as a great promising candidate for bone, oral, and maxillofacial tissue engineering applications.


Asunto(s)
Diferenciación Celular , Pulpa Dental/citología , Glicerofosfatos/farmacología , Nanofibras/química , Osteogénesis , Poliésteres/farmacología , Polietilenglicoles/farmacología , Células Madre/citología , Fosfatasa Alcalina/metabolismo , Animales , Calcio/metabolismo , Diferenciación Celular/efectos de los fármacos , Células Cultivadas , Liberación de Fármacos , Módulo de Elasticidad , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Nanofibras/ultraestructura , Osteogénesis/efectos de los fármacos , Células Madre/efectos de los fármacos , Células Madre/ultraestructura , Resistencia a la Tracción
19.
J Cell Biochem ; 120(9): 15814-15822, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31069835

RESUMEN

Reconstruction of the bladder wall plays an important role in improving its function in patients with urinary bladder dysfunction. Tissue engineering has been trying to introduce biocompatible nanofibers as scaffolds for bladder wall matrix substitutes. In this study a composite nanofibrous scaffold was fabricated from polyacrylonitrile (PAN) and polyethylene oxide (PEO) blend by electrospinning method and then its morphological and mechanical characteristics was evaluated by scanning electron microscopy (SEM), tensile, and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Then smooth muscle cell (SMC) differentiation supportive capacity of PAN-PEO nanofibers was investigated by culturing of human adipose tissue-derived mesenchymal stem cells (AT-MSCs) on this scaffold and then its differentiation potential in different groups was investigated using SMC-related gene and protein markers. SEM and MTT results demonstrated that PAN-PEO supported AT-MSCs attachment, growth and proliferation, especially at early times after cell seeding. The obtained results from real-time reverse transcription polymerase chain reaction revealed that collagen-I-α1, collagen-III-α1, α-smooth muscle actin (α-SMA), calponin1, SM22α, caldesmon1, elastin, and myosin heavy chain (MHC) genes were expressed in AT-MSCs cultured on PAN-PEO significantly higher than those stem cells that cultured on the culture plate as a control. In addition α-SMA and MHC proteins were also expressed in AT-MSCs cultured on PAN-PEO significantly higher than control. According to the results PAN-PEO nanofibrous scaffold showed a positive AT-MSCs-seeded PAN-PEO has a great promising potential to use in bladder tissue engineering applications.


Asunto(s)
Resinas Acrílicas/química , Células Madre Mesenquimatosas/citología , Polietilenglicoles/química , Ingeniería de Tejidos/métodos , Vejiga Urinaria/citología , Diferenciación Celular , Proliferación Celular , Células Cultivadas , Humanos , Células Madre Mesenquimatosas/metabolismo , Microscopía Electrónica de Rastreo , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/metabolismo , Nanofibras/química , Andamios del Tejido , Vejiga Urinaria/metabolismo
20.
Proc Natl Acad Sci U S A ; 113(26): 7094-9, 2016 06 28.
Artículo en Inglés | MEDLINE | ID: mdl-27307440

RESUMEN

Beyond state-of-the-art lithium-ion battery (LIB) technology with metallic lithium anodes to replace conventional ion intercalation anode materials is highly desirable because of lithium's highest specific capacity (3,860 mA/g) and lowest negative electrochemical potential (∼3.040 V vs. the standard hydrogen electrode). In this work, we report for the first time, to our knowledge, a 3D lithium-ion-conducting ceramic network based on garnet-type Li6.4La3Zr2Al0.2O12 (LLZO) lithium-ion conductor to provide continuous Li(+) transfer channels in a polyethylene oxide (PEO)-based composite. This composite structure further provides structural reinforcement to enhance the mechanical properties of the polymer matrix. The flexible solid-state electrolyte composite membrane exhibited an ionic conductivity of 2.5 × 10(-4) S/cm at room temperature. The membrane can effectively block dendrites in a symmetric Li | electrolyte | Li cell during repeated lithium stripping/plating at room temperature, with a current density of 0.2 mA/cm(2) for around 500 h and a current density of 0.5 mA/cm(2) for over 300 h. These results provide an all solid ion-conducting membrane that can be applied to flexible LIBs and other electrochemical energy storage systems, such as lithium-sulfur batteries.

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