Physico-chemistry and Cytotoxicity of Tenofovir-Loaded Acid Phosphatase-Responsive Chitosan Nanoparticles.

This study assesses the in vitro release of tenofovir (TFV)-loaded triphosphate (TPP) cross-linked chitosan nanoparticles (NPs) catalyzed by human prostatic acid phosphatase (hPAP) for 24 h. The physico-chemical characterization of the NPs included particle mean diameter (PMD), zeta potential (ζ), percent drug encapsulation efficiency (% EE), Fourier transform infra-red (FTIR) spectroscopy, powder X-ray diffractometry analysis (PXRD), and drug release kinetics. The first-order rate constant (k) and activation energy (E) of the cross-link (TPP) are determined by the integrated rate law and Arrhenius's equations.

Engineering fast dissolving sodium acetate mediated crystalline solid dispersion of docetaxel.

It is hypothesized that a novel crystalline solid dispersion (CSD) of docetaxel (C-DXT) can be engineered by dispersing native docetaxel (DXT, a BCS class II drug) in sodium acetate crystal (SA). DXT is dissolved in glacial acetic/SA solution and freeze-dried. The resulting C-DXT is characterized by differential scanning calorimetry (DSC), powder X-ray analysis (PXRD), LC-MS/MS, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Quartz crystal microbalance with dissipation monitoring (QCM-D) and dynamic light scattering (DLS).

Label-Free Ferrocene-Loaded Nanocarrier Engineering for In Vivo Cochlear Drug Delivery and Imaging.

It is hypothesized that ferrocene (FC)-loaded nanocarriers (FC-NCs) are safe label-free contrast agents for cochlear biodistribution study by transmission electron microscopy (TEM). To test this hypothesis, after engineering, the poly(epsilon-caprolactone)/polyglycolide NCs are tested for stability with various types and ratios of sugar cryoprotectants during freeze-drying. Their physicochemical properties are characterized by UV-visible spectroscopy, dynamic light scattering, Fourier transform infrared spectroscopy, and scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM/EDS).

Sodium Acetate Coated Tenofovir-Loaded Chitosan Nanoparticles for Improved Physico-Chemical Properties.

Purpose: It is hypothesized that sodium acetate (SA) can be used for in situ coating of drug loaded chitosan NPs for improved physico-chemical properties.

Methods: Tenofovir (TFV) is used as a model drug. Uncoated chitosan NPs are prepared by ionic gelation.

Strong microwave absorption of hydrogenated wide bandgap semiconductor nanoparticles.

Electromagnetic interactions in the microelectronvolt (μeV) or microwave region have numerous important applications in both civil and military fields, such as electronic communications, signal protection, and antireflective coatings on airplanes against microwave detection. Traditionally, nonmagnetic wide-bandgap metal oxide semiconductors lack these μeV electronic transitions and applications. Here, we demonstrate that these metal oxides can be fabricated as good microwave absorbers using a 2D electron gas plasma resonance at the disorder/order interface generated by a hydrogenation process.

Evaluation of degradation kinetics and physicochemical stability of tenofovir.

Tenofovir (TFV) has been proven to prevent the transmission of the Human Immunodeficiency Virus (HIV) through the vagina. But, there is little information available about its stability under various storage and stress conditions. Hence, this study aimed to investigate the degradation behavior and physicochemical stability of TFV using liquid chromatography coupled mass spectrometry (LC-MS) and solid state X-ray diffraction (XRD) analyses.

Resveratrol-loaded nanocarriers: formulation, optimization, characterization and in vitro toxicity on cochlear cells.

The present work aimed to investigate the suitability of polymeric nanoparticles (NPs) loaded with resveratrol (RES) for drug delivery to cochlear cells. RES-loaded NPs were prepared by a solvent-diffusion method without surfactant. The Box-Behnken design was used to study the effect of the formulation variables on the particle mean diameter (PMD), polydispersity index (PDI), zeta-potential (ζ), percent drug encapsulation efficiency (EE%), and ratio between NP size before and after freeze-drying (Sf/Si).

Influence of surface chemistry on cytotoxicity and cellular uptake of nanocapsules in breast cancer and phagocytic cells.

The present work tests the hypothesis that stabilizers have a critical role on nanocarrier stealthiness and anticancer drug efficacy. Two different types of docetaxel (Doc)-loaded nanocapsules (NCs) stabilized with polysorbate 80 (NC(T80)) and polyvinyl alcohol (NC(PVA)) were synthesized using the emulsion solvent diffusion method. These NCs were characterized for particle mean diameter (PMD), drug content, morphology, surface composition, and degree of crystallinity.

Uptake and cytotoxicity of docetaxel-loaded hyaluronic acid-grafted oily core nanocapsules in MDA-MB 231 cancer cells.

Purpose: It is hypothesized that docetaxel (Doc)-loaded hyaluronic acid (HA)-polyethylene glycol/poly(ε-caprolactone)-grafted oily core nanocapsules (NCs) can enhance the drug cytotoxicity and uptake in CD44 expressing breast cancer (BC) cells (MDA-MB 231).

Methods: NCs were prepared, optimized and characterized by dynamic light scattering, transmission electron microscopy (TEM), and powder X-ray diffraction (PXRD). In vitro cytotoxicity tests [MTS, level of reactive oxygen species (ROS) and level of reduced glutathione (GSH)] were performed in BC cells.

Built-in electric field-assisted surface-amorphized nanocrystals for high-rate lithium-ion battery.

High-power batteries require fast charge/discharge rates and high capacity besides safe operation. TiO2 has been investigated as a safer alternative candidate to the current graphite or incoming silicon anodes due to higher redox potentials in effectively preventing lithium deposition. However, its charge/discharge rates are reluctant to improve due to poor ion diffusion coefficients, and its capacity fades quickly with rate as only thinner surface layers can be effectively used in faster charge/discharge processes.

Directional heat dissipation across the interface in anatase-rutile nanocomposites.

Understanding the structures and properties of interfaces in (nano-)composites helps to reveal their important influence on reactivity and overall performance. TiO2 is a technologically important material, and anatase/rutile TiO2 composites have been shown to display enhanced photocatalytic performance over pure anatase or rutile TiO2. This has been attributed to a synergistic effect between the two phases, but the origin of this effect as well as the structure of the interface has not been established.

Spray drying tenofovir loaded mucoadhesive and pH-sensitive microspheres intended for HIV prevention.

Purpose: To develop spray dried mucoadhesive and pH-sensitive microspheres (MS) based on polymethacrylate salt intended for vaginal delivery of tenofovir (a model HIV microbicide) and assess their critical biological responses.

Methods: The formulation variables and process parameters are screened and optimized using a 2(4-1) fractional factorial design. The MS are characterized for size, zeta potential, yield, encapsulation efficiency, Carr's index, drug loading, in vitro release, cytotoxicity, inflammatory responses and mucoadhesion.

Entrapment and release kinetics of furosemide from pegylated nanocarriers.

This study was designed to test the hypothesis that furosemide (Fur) can be entrapped into surfactant free pegylated nanocarriers (NCs) for controlled drug release. To test this hypothesis, Fur-loaded NCs were prepared by emulsion solvent diffusion method. A 2(3) factorial design was used to optimize the effect of three formulation variables [amounts of Fur (X(1)), poly(lactic-co-glycolic acid) (X(2)) and poly-ε-caprolactone-polyethylene glycol (X(3))] on particle mean diameter (Y(1)), polydispersity index (PDI, Y(2)), and percent drug encapsulation efficiency (EE%, Y(3)).

Encapsulation of docetaxel in oily core polyester nanocapsules intended for breast cancer therapy.

This study is designed to test the hypothesis that docetaxel [Doc] containing oily core nanocapsules [NCs] could be successfully prepared with a high percentage encapsulation efficiency [EE%] and high drug loading. The oily core NCs were generated according to the emulsion solvent diffusion method using neutral Labrafac CC and poly(d, l-lactide) [PLA] as oily core and shell, respectively. The engineered NCs were characterized for particle mean diameter, zeta potential, EE%, drug release kinetics, morphology, crystallinity, and cytotoxicity on the SUM 225 breast cancer cell line by dynamic light scattering, high performance liquid chromatography, electron microscopies, powder X-ray diffraction, and lactate dehydrogenase bioassay.

Thermodynamics of drug nanoencapsulation: case study of phenytoin-poly (D, L-lactide) nanocarrier.

In order to rationalize the nanoencapsulation process, a thermodynamic analysis allowed to predict the limit of a model drug (phenytoin, PHT) loading into poly (d, l-lactic acid) nanocarrier (PLA NC) prepared by solvent displacement method. The NC were characterized for size, morphology, thermal behavior and crystallography by dynamic light scattering, electron microscopies, differential scanning calorimetry, and powder X-ray diffraction, respectively. The drug loading, encapsulation efficiency (EE) and in vitro drug release profile were determined using high performance liquid chromatography.

Optimization of formulation variables affecting spray-dried oily core nanocapsules by response surface methodology.

The formulation variables required for the production of spray-dried oily core nanocapsules (NCs) with targeted size and drug payload were optimized using a Box-Behnken experimental design. These NCs were characterized for size, morphology, encapsulation efficiency (EE%) and drug release kinetics, crystallinity, and density, by dynamic light scattering, electron microscopy, ultraviolet spectrometry, powder X-ray diffraction, and density-gradient centrifugation, respectively. The size of the NCs ranged from 208.

Formulation of dacarbazine-loaded cubosomes. Part III. Physicochemical characterization.

The purpose of this study was to investigate the physicochemical properties of dacarbazine-loaded cubosomes. The drug-loaded cubosome nanocarriers were prepared by a fragmentation method and then freeze dried. They were then characterized for size, morphology, thermal behavior, and crystallography using dynamic light scattering, transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and powder X-ray diffraction (PXRD), respectively.