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Viscum album L., popularly known as mistletoe, is well known for its anti-cancer properties, and the pharmaceutical application of hydroalcoholic dry extracts is still limited due to its low solubility in aqueous media, and physicochemical instability. The Pluronic® F127 is an amphiphilic polymer, which permits the solubilization of lipophilic and hydrophilic compounds. In this investigation, physicochemical features of hydrogel containing V. album dry extract (VADE-loaded-hydrogel) were performed by: dynamic light scattering (DLS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and transmission electron microscopy (TEM). VADE-loaded-hydrogel presented nanometer-size micelles with volume distribution ranging from 10.58 nm to 246.7 nm, and a polydispersity index of 0.441. The sample thermal analyses (TG and DSC) showed similar decomposition curves; however, the thermal events indicated an increase in thermal stability in relation to the presence of the extract. In addition to these interesting pharmaceutical features, IC50 values of 333.40 µg/mL and >1000 µg/mL were obtained when tumor (SCC-25) and non-tumor (L929) cells were incubated with VADE-loaded-hydrogel, respectively. The optical and ultrastructural cellular analysis confirmed the tumor selectivity since the following alterations were detected only in SCC-25 cells: disorganization of plasmatic membrane; an increase of cytoplasmatic vacuole size; alteration in the cristae mitochondrial shape; and generation of amorphous cellular material. These results emphasize the promising antitumoral potential of VADE-loaded-hydrogel as an herbal drug delivery system via in vitro assays.

Silica-based (SiO2) poly(3-hydroxybutyrate) (PHB) nanocomposites were obtained via an in situ sol–gel route in three distinct particle concentrations (1, 5, and 7.5% by weight of PHB). The polymer hybrids formed were analyzed via wide-angle X-ray diffraction (WAXD), small-angle X-ray scattering (SAXS), Fourier transform infrared (FTIR) spectroscopy, and time-domain nuclear magnetic resonance relaxometry (TD-NMR). The SiO2 inorganic structure displayed surface fractal features at low concentration (1 wt%) and denser agglomerates at higher concentrations (5 and 7.5 wt%). FTIR and SAXS results confirmed the formation of the inorganic matrix amid the polymer chains with different levels of distribution and organization. WAXD and TD-NMR results suggested the SiO2 influence on the PHB crystallinity degree, which was reflected on the polymer’s molecular dynamics with a nonlinear dependence of particles concentration in the PHB matrix.

Background: The demand for novel biomaterials has been exponentially rising in the last years as well as the searching for new technologies able to produce more efficient products in both drug delivery systems and regenerative medicine. Objective: The technique that can pretty well encompass the needs for novel and high-end materials with a relatively low-cost and easy operation is the electrospinning of polymer solutions. Methods: Electrospinning usually produces ultrathin fibers that can be applied in a myriad of biomedical devices including sustained delivery systems for drugs, proteins, biomolecules, hormones, etc that can be applied in a broad spectrum of applications, from transdermal patches to cancer-related drugs. Results: Electrospun fibers can be produced to mimic certain tissues of the human body, being an option to create new scaffolds for implants with several advantages. Conclusions: In this review, we aimed to encompass the use of electrospun fibers in the field of biomedical devices, more specifically in the use of electrospun nanofibers applications toward the production of drug delivery systems and scaffolds for tissue regeneration.