Polyvinyl Alcohol Nanofibers Blends as Drug Delivery System in Tissue Regeneration.

Nanofibers have shown promising clinical results in the process of tissue regeneration since they provide a similar structure to the extracellular matrix of different tissues, high surface-to-volume ratio and porosity, flexibility, and gas permeation, offering topographical features that stimulate cell adhesion and proliferation. Electrospinning is one of the most used techniques for manufacturing nanomaterials due to its simplicity and low cost. In this review, we highlight the use of nanofibers produced with polyvinyl alcohol and polymeric associations (PVA/blends) as a matrix for release capable of modifying the pharmacokinetic profile of different active ingredients in the regeneration of connective, epithelial, muscular, and nervous tissues. Articles were selected by three independent reviewers by analyzing the databases, such as Web of Science, PubMed, Science Direct, and Google Scholar (last 10 years). Descriptors used were "nanofibers", "poly (vinyl alcohol)", "muscle tissue", "connective tissue", "epithelial tissue", and "neural tissue engineering". The guiding question was: How do different compositions of polyvinyl alcohol polymeric nanofibers modify the pharmacokinetics of active ingredients in different tissue regeneration processes? The results demonstrated the versatility of the production of PVA nanofibers by solution blow technique with different actives (lipo/hydrophilic) and with pore sizes varying between 60 and 450 nm depending on the polymers used in the mixture, which influences the drug release that can be controlled for hours or days. The tissue regeneration showed better cellular organization and greater cell proliferation compared to the treatment with the control group, regardless of the tissue analyzed. We highlight that, among all blends, the combinations PVA/PCL and PVA/CS showed good compatibility and slow degradation, indicating their use in prolonged times of biodegradation, thus benefiting tissue regeneration in bone and cartilage connective tissues, acting as a physical barrier that results in guided regeneration, and preventing the invasion of cells from other tissues with increased proliferation rate.

Physicochemical Characterization of Silver Sulfadiazine in Polymeric Wound Dressings.

The insertion of topical antimicrobials in wound treatment represented an important role in patient management. Among these agents, silver sulfadiazine (AgSD), introduced in the therapy of wounds and burns in the 1960s, is considered the gold standard in treatment due to its mechanism of action, in addition to its proven efficacy and safety. The association of AgSD with polymers for the development of curative formulations has been reported. The evaluation of the physical-chemical properties of these systems with the aid of analytical techniques of characterization is essential for the determination of their activities, besides allowing the detection of possible incompatibilities between AgSD and polymers. Thus, this review presents the main techniques of physicochemical characterization used in the evaluation of systems containing AgSD with curative purposes in order to provide parameters to ensure the efficacy and safety of these new therapeutic options. Microscopic, thermoanalytical, and spectroscopic techniques, for example, provide information on system properties such as surface chemical composition, crystallinity, morphology, and thermal stability of curative formulations containing AgSD. These techniques are important in the selection of the most appropriate techniques during the development of a polymeric curative system containing AgSD, in addition to providing information for cost reduction of a possible scale-up and the establishment of methodologies for quality control of these systems to ensure their efficacy and safety.

Photodynamic potential of hexadecafluoro zinc phthalocyanine in nanostructured lipid carriers: physicochemical characterization, drug delivery and antimicrobial effect against Candida albicans.

This study aims to develop and characterize NCL loaded with ZnF16Pc (Pc) for application in antimicrobial photodynamic therapy. For the development of the NLC, the fusion-emulsification technique followed by sonication was applied. NLC and Pc-NLC were characterized in terms of mean diameter (Dm.n), polydispersity index (PdI), zeta potential (ZP), encapsulation efficiency (%EE), transmission electron microscopy (TEM), differential scanning (DSC), photobleaching and singlet oxygen generation in cellular systems (SOSG), and in vitro release assays performed by the beaker method, using dialysis membranes. Cell viability was performed by colony forming units (CFU/mL). The mean size of NLC and Pc-NLC was 158 nm ± 1.49 to 161.80 nm and showed PdI < 0.3 and ZP between -17.8 and -19.9, and stable during storage time (90 days). The TEM presented spherical particles, the Pc-NLC promoted the encapsulation of 75.57% ± 0.58. DSC analysis confirmed that there was no incompatibility between Pc and NLC. The analysis of the photodegradation profile proved to be photostable after encapsulation and this corroborates the data obtained by SOSG. In vitro release showed controlled and prolonged release. PDT Pc-NLC exhibited greater antifungal effect against C. albicans (3 log10 reduction) than Pc-NLC without light (1 log10 reduction). NLC can be an alternative to the application of Pc and improve the effect during PDT treatment.

Monoclonal Antibodies Carried in Drug Delivery Nanosystems as a Strategy for Cancer Treatment.

Monoclonal antibodies carried in nanosystems have been extensively studied and reported as a promising tool for the treatment of various types of cancers. Monoclonal antibodies have great advantages for the treatment of cancer because their protein structure can bind to the target tissue; however, it has some challenges such as denaturation following heat exposure and extreme values of pH, temperature and solvents, the ability to undergo hydrolysis, oxidation and deamination and the formation of non-native aggregates, which compromise drug stability to a large extent. In addition to these characteristics, they suffer rapid elimination when in the blood, which results in a short half-life and the production of neutralizing antibodies, rendering the doses ineffective. These challenges are overcome with encapsulation in nanosystems (liposomes, polymer nanoparticles, cyclodextrins, solid lipid nanoparticles, nanostructured lipid carriers, dendrimers and micelles) due to the characteristics of improving solubility, permeability, and selectivity only with tumor tissue; with that, there is a decrease in side effects beyond controlled release, which is critical to improving the therapeutic efficacy of cancer treatment. The article was divided into different types of nanosystems, with a description of their definitions and applications in various types of cancers. Therefore, this review summarizes the use of monoclonal antibodies encapsulated in nanosystems and the description of clinical studies with biosimilars. Biosimilars are defined as products that are similar to monoclonal antibodies which are produced when the patent for the monoclonal antibodies expires.

Prospective application of phthalocyanines in the photodynamic therapy against microorganisms and tumor cells: A mini-review.

Phthalocyanines are second-generation photosensitizers with photophysical and photochemical properties improved, in comparison to the first-generation. Also, these have shown to be phototoxic against several types of microorganisms and tumor cells. However, challenges such as low solubility in the physiological environment make its single administration unfeasible. Therefore, this review discusses a unique combination of phthalocyanine-loaded in drug delivery carriers for photodynamic therapy in different pathologies' treatment, including nanoemulsion, liposomes, and lipid nanoparticles in an attempt to overcome low solubility drawback. Furthermore, the latest advances to elucidating its mechanisms of action are shown. Subsequently, the manuscript was divided into ten different types of phthalocyanines for medical applications, with a description of their definitions and applications, summarizing the latest preclinical results founded in recent literature.

Bicontinuous microemulsions containing Melaleuca alternifolia essential oil as a therapeutic agent for cutaneous wound healing.

The Melaleuca alternifolia essential oil (MEO) has been widely used due to its healing and antimicrobial action. Its incorporation into drug delivery systems is a reality, and numerous studies have already been developed for this purpose. In this regard, the aim of this work was to develop, characterize, and evaluate the in vivo pharmacological activity of bicontinuous microemulsions (BME) containing MEO. Through diagram construction, a formulation consisting of Kolliphor® HS 15 (31.05%), Span® 80 (3.45%), isopropyl myristate (34.5%), and distilled water (31%) was selected and MEO was incorporated in the proportion of 3.45% (v/v). Morphological analysis characterization confirms that the system studied herein is a BME. The evaluated formulation showed physicochemical characteristics that allow its topical use. Rheologically, samples were characterized as pseudo-plastic non-Newtonian thixotropic fluids. The chromatographic method developed is in accordance with the current recommendations. The extraction method used assured a 100% recovery of the pharmacological marker (terpinen-4-ol). In vivo studies suggest that BME loaded with MEO may contribute to the healing process of skin wounds. In addition, it demonstrated antibacterial activity for Gram-positive and Gram-negative bacteria. Therefore, the BME system loaded with MEO is promising as a healing and antimicrobial agent for skin wounds.Graphical abstract.

Antifungal activity of topical microemulsion containing a thiophene derivative.

Fungal infections have become a major problem of worldwide concern. Yeasts belonging to the Candida genus and the pathogenic fungus Cryptococcus neoformans are responsible for different clinical manifestations, especially in immunocompromised patients. Antifungal therapies are currently based on a few chemotherapeutic agents that have problems related to effectiveness and resistance profiles. Microemulsions are isotropic, thermodynamically stable transparent systems of oil, water and surfactant that can improve the solubilization of lipophilic drugs. Taking into account the need for more effective and less toxic drugs along with the potential of thiophene derivatives as inhibitors of pathogenic fungi growth, this study aimed to evaluate the antifungal activity of a thiophene derivative (5CN05) embedded in a microemulsion (ME). The minimum inhibitory concentration (MIC) was determined using the microdilution method using amphotericin B as a control. The formulations tested (ME- blank and ME-5CN05) showed physico-chemical properties that would allow their use by the topical route. 5CN05 as such exhibited moderate or weak antifungal activity against Candida species (MIC = 270-540 µg . mL(-1)) and good activity against C. neoformans (MIC = 17 µg . mL(-1)). Candida species were susceptible to ME-5CN05 (70-140 µg . mL(-1)), but C. neoformans was much more, presenting a MIC value of 2.2 µg . mL(-1). The results of this work proved promising for the pharmaceutical industry, because they suggest an alternative therapy against C. neoformans.

Physico-chemical quality parameters of herbal products from Agave sisalana.

Agave sisalana components have great potential in different pharmaceutical applications, but the quality of herbal raw materials is essential to reach the desired product specifications. In this work, we investigated the physico-chemical quality parameters of bole and wastes from decortication of A. sisalana leaves. The statistically significant variations among products suggest different pharmaceutical applications for each of them.

Inulin-type fructans: a review on different aspects of biochemical and pharmaceutical technology.

Inulin is a natural storage polysaccharide with a large variety of food and pharmaceutical applications. It is widely distributed in plants, being present as storage carbohydrate in more than 30,000 vegetable products. Due to their wide distribution in nature and significant role in industry, the extraction, isolation and characterization of inulin-type fructans are gaining attention in recent years. Inulin sources have recently received increasing interest as they are a renewable raw material for the production of bioethanol, fructose syrup, single-cell protein and single cell oil, obtainment of fructooligosaccharides and other useful products. This review focuses on the state-of-the-art of biochemical and pharmaceutical technology of inulin-type fructans.