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This research focuses on the synthesis and adhesive properties of mucoadhesive mats, prepared with poly(vinylic alcohol) as a base polymer for the oromucosal release of propranolol (PRO) by the electrospinning technique. The nanofibers mats were evaluated by scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry; in vitro drug entrapment efficiency, degradation time, and adhesion studies were performed. SEM images of the electrospun mats show the correct formation of fibers with a variable diameter and porosity. Thermal studies indicate excellent thermal stability of the scaffolds, The fibrous mats loaded with 10% of the drug exhibit the best thermal stability with decomposition after 450°C. In vitro studies indicate a drug content of 88% loaded in the mats. In the cytotoxicity test, loaded mat presents cell proliferations of 97% and 88% for drug concentrations of 10% an 15%, respectively. To conclude, the formed electrospun adhesive mats exhibited excellent thermal stability, adhesive properties, and drug entrapment efficiency, promising features for a successful drug topical release system on mucosal tissue in the oral cavity.

The antimicrobial bioactivity of silver nanoparticles is well known, and they can be used widely in many applications, becoming especially important in the biomedical industry. On the other hand, the electrospun nanofibers possess properties that can enhance silver nanoparticle applicability. However, silver nanoparticle bioactivity differs depending on the loading of silver ions into electrospun nanofibers. This review is aimed at comparing different silver incorporation methods into electrospun nanofibers and their antimicrobial activity, discussing each procedure’s limitations, and presenting the most promising one. This review showed that the preferred techniques for incorporating silver nanoparticles were direct blending and ultraviolet irradiation methods due to their simplicity and efficient results. Besides, polyacrylonitrile nanofibers (PAN) have been the most reported system loaded with silver nanoparticles. Finally, independently of the technique used, silver nanoparticle-loaded nanofibers show high antimicrobial activity in all cases.

The search for a suitable bone replacement is of great importance due to the difficulty to use autologous transplants. Hence, the objective of this work is to compare the temperature effect on the porosity and average pore diameter of hydroxyapatite porous scaffolds fabricated by the salt leaching method. Hydroxyapatite porous scaffolds fabricated by the salt leaching technique were sintered from ~150 to 1000 °C. Synthesized hydroxyapatite was assessed by X-ray diffraction (XRD). Zeta potential at different temperatures was evaluated. Specimens were characterized using scanning electron microscopy (SEM) and Raman analysis. The results showed that significant porosity (57%) and pore size (49 µm) occurred with a thermal treatment above ~ 850 °C for scaffolds that were pre-sintered at 1050 °C.

Sildenafil citrate (SC) has proved to be an effective and inexpensive drug for the treatment of pulmonary arterial hypertension (PAH). This study aims to synthesize electrospun, submicron fiber scaffolds of poly(vinyl alcohol) (PVA) and poly(vinyl pyrrolidone) (PVP) loaded with SC for fast drug dissolution and its potential use in the treatment of PAH. These fiber scaffolds were prepared through the electrospinning technique. The chemical composition of the nanofibers was analyzed by Fourier transform infrared spectroscopy. Thermal stability was studied by thermogravimetric analysis and polymeric transitions by differential scattering calorimetry. Surface analysis of the nanofibers was studied by field emission scanning electron microscopy. The wetting and dissolution time of the scaffolds and drug release rate were studied as well. The drug-loaded PVP fibers showed better quality regarding size and homogeneity compared to drug-loaded PVA fibers. These fibers encapsulated approximately 2.5 mg/cm2 of the drug and achieved immediate controlled released rate, which is encouraging for further studies leading to an alternative treatment of PAH in children.

The main goal of this work is the design of a mucoadhesive system, based on three layers for the unidirectional release of dexamethasone sodium phosphate (DEX-F) for possible use in the oral mucosa...

Electrospun nanofibers have been widely studied for many medical applications. They can be designed with specific features, including mucoadhesive properties. This review summarizes the polymeric scaffolds obtained by the electrospinning process that has been applied for drug release in different mucosal sites such as oral, ocular, gastroenteric, vaginal, and nasal. We analyzed the electrospinning parameters that have to be optimized to create reproducible and efficient mucoadhesive nanofibers, among them are: electrical field, polymer concentration, viscosity, flow rate, needle-collector distance, solution conductivity, solvent, environmental parameters, and electrospinning setup. We also revised the mucoadhesive theories as well as the mucoadhesive properties of the polymers used. This review shows that the most studied mucosal site is the oral cavity, because it is accessible and easy to evaluate, while the rest are uncomfortable for the patient and difficult to assess in vivo. We found problems that need to be solved for mucoadhesive electrospun nanofibers, such as improving adhesion strength and mucosal permanence time, and the design of unidirectional release, multilayer systems for the treatment of several pathologies, to ensure the drug concentration in the tissue or target organ.

Skin burns and ulcers are considered hard-to-heal wounds due to their high infection risk. For this reason, designing new options for wound dressings is a growing need. The objective of this work is to investigate the properties of poly (&epsilon, caprolactone)/poly (vinyl-pyrrolidone) (PCL/PVP) microfibers produced via electrospinning along with sorbents loaded with Argovit&trade, silver nanoparticles (Ag-Si/Al2O3) as constituent components for composite wound dressings. The physicochemical properties of the fibers and sorbents were characterized using scanning electron microscopy (SEM), differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR) and inductively coupled plasma optical emission spectroscopy (ICP-OES). The mechanical properties of the fibers were also evaluated. The results of this work showed that the tested fibrous scaffolds have melting temperatures suitable for wound dressings design (58&ndash, 60 &deg, C). In addition, they demonstrated to be stable even after seven days in physiological solution, showing no macroscopic damage due to PVP release at the microscopic scale. Pelletized sorbents with the higher particle size demonstrated to have the best water uptake capabilities. Both, fibers and sorbents showed antimicrobial activity against Gram-negative bacteria Pseudomona aeruginosa and Escherichia coli, Gram-positive Staphylococcus aureus and the fungus Candida albicans. The best physicochemical properties were obtained with a scaffold produced with a PCL/PVP ratio of 85:15, this polymeric scaffold demonstrated the most antimicrobial activity without affecting the cell viability of human fibroblast. Pelletized Ag/Si-Al2O3-3 sorbent possessed the best water uptake capability and the higher antimicrobial activity, over time between all the sorbents tested. The combination of PCL/PVP 85:15 microfibers with the chosen Ag/Si-Al2O3-3 sorbent will be used in the following work for creation of wound dressings possessing exudate retention, biocompatibility and antimicrobial activity.

Recently, electrospun polymeric nanofibers have proven to be an interesting strategy for drug delivery systems application. The high surface-to-volume ratio of the fibers can improve some processes, such as cell binding and proliferation, drug loading, and mass transfer processes. One of the most im-portant and studied areas of electrospinning is in the drug delivery field, for the controlled release of active substances ranging from antibiotics and anticancer agents to macromolecules such as proteins and DNA. The advantage of this method is that a wide variety of low solubility drugs can be loaded into the fibers to improve their bioavailability or to attain controlled release. This review presents an overview of the re-ported drugs loaded into polymeric nanofibers, to be used as drug delivery systems. For instance, it pre-sents the reports on drugs with different bioactivities such as anti-inflammatory, anti-microbial, anticancer, cardiovascular, anti-histamine, gastrointestinal, palliative and contraceptive drugs, etc. It also analyzes the electrospinning techniques used in each system, as well as the polymers used as matrices for the prepara-tion of the nanofibers; unfolding the advantages of electrospun polymeric nanofibers over other drug delivery systems. This review intends to enlist and summarize the reported literature concerning this topic. In addition, it proposes future research in the field

Conventional pharmaceuticals generally display the inability to transport active ingredients directly to specific regions of the body, amongst some of their main limitations. The distribution of the drugs in the circulatory system may lead to undesired toxicity, and therefore, adverse reactions. To address this situation, a selective transport of drugs is required, that is, releasing drugs specifically to the site of action in appropriate concentrations and in the right time. To achieve this goal, it is necessary to develop delivery systems that respond to several features, such as low toxicity, optimum properties for the transport and release of the drug, as well as a long half-life in the body. This feature paper critically provides an overview of different strategies of controlled drug release for two model antineoplasic drugs, i.e. doxorubicin (DOX) and 5-fluorouracil (5-FU). Any of the presented strategies for drug release possess advantages and disadvantages, and the selection of the strategy used will depend on the targeted tissue and nature of the drug.

International audience; The electrospinning technique is a useful and versatile approach for conversion of polymeric solutions into continuous fibers, ranging from a few micrometers (10-100 μm) to the scale of nanometers (10-100 nm) in diameters. This technique can be used in a vast number of polymers, in some cases after modifying them to the required properties. The high surface-to-volume ratio of the fibers can improve some processes like cell binding and proliferation, drug loading, and mass transfer processes. One of the most important and studied areas of electrospinning is in the drug delivery field, for the controlled release of active substances ranging from antibiotics and anticancer agents, to macromolecules such as proteins and DNA. The advantage of this method is that a wide variety of low solubility drugs can be loaded into the fibers to improve their bioavailability or to attain controlled release. This review presents an overview of the reported drugs loaded into electrospun polymeric nanofibers to be used as drug delivery systems. These drugs are classified by their applications in pharmacy.

Electrospun nanofibers are used for many applications due to their large surface area, mechanical properties, and bioactivity. Bacterial biofilms are the cause of numerous problems in biomedical devices and in the food industry. On the other hand, these bacterial biofilms can produce interesting metabolites. Hence, the objective of this study is to evaluate the efficiency of poly (Ɛ- caprolactone)/Curcumin (PCL/CUR) nanofibers to promote bacterial biofilm formation. These scaffolds were characterized by scanning electron microscopy (SEM), which showed homogeneous fibers with diameters between 441&ndash, 557 nm, thermogravimetric analysis and differential scanning calorimetry (TGA and DSC) demonstrated high temperature resilience with degradation temperatures over &gt, 350 &deg, C, FTIR and 1H-NMR serve as evidence of CUR incorporation in the PCL fibers. PCL/CUR scaffolds successfully promoted the formation of Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa biofilms. These results will be valuable in the study of controlled harvesting of pathogenic biofilms as well as in metabolites production for biotechnological purposes.

Los implantes de fijacion de fracturas se emplean para resolver una fractura de hueso, actualmente hay una variedad de dispositivos como: agujas intramedulares, tachuelas y tornillos metalicos. Su funcion es estabilizar fragmentos de hueso en su sitio correcto durante su reparacion osea, para lograr una vascularizacion temprana. El objetivo de este estudio es sintetizar y caracterizar fisicoquimicamente hidroxiapatita sintetica para fabricar filmes de PLGA 50:50/HAp. Se utilizo la tecnica de espectroscopia infrarroja transformada de Fourier (FTIR) para buscar grupos funcionales principales. El analisis termogravimetrico (TGA) y la calorimetria diferencial de barrido (DSC) para evaluar el comportamiento de los filmes con respecto a la temperatura y caracterizar la superficie con microscopia electronica de barrido (SEM). El espectro FTIR presenta senales de gran interes: se observa la zona aromatica entre 1600 cm-1-1400 cm-1, senal caracteristica de los aldehidos aromaticos(C=O) a los 1700 cm-1, alquenos aromaticos (C=O) a los 1300 cm-1 con traslapes de senales –C-H, =C-H, adicional una cuarta senal muy ancha entre los 3400-2400cm-1 asignada a –OH. Las micrografias de SEM, presentan homogeneidad en la superficie. El termograma TGA, se observa una perdida de material a los 180°C del 5% aproximadamente y otro a 252°C del 10%. Finalmente, el termograma DSC, se observa alrededor de los 50 a 70°C, un ligero y amplio cambio nos permite creer que esa es la zona de transicion vitrea del material, ademas se encontro un pico alrededor de los 52.07°C, donde se propone que ocurre la degradacion de la formulacion. Como trabajo futuro se realizaran pruebas de biocompatibilidad y degradacion. Palabras clave: Fracturas oseas; Filmes; PLGA/HAp; Caracterizacion fisicoquimica. Abstract: Fracture fixation implants are used to resolve a bone fracture, currently; there are a variety of devices such as intramedullary needles, tacks and, metal screws. Its function is to stabilize bone fragments in their correct place during their bone repair, to achieve an early vascularization. The objective of this study is to synthesize and physiochemically characterize of synthetic hydroxyapatite for the manufacturing of PLGA 50: 50 / Hap films. Through the Fourier transform infrared spectroscopy technique (FTIR) to look for main functional groups. Thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) to evaluate the behavior of films with respect to temperature and characterize the surface with scanning electron microscopy (SEM). The FTIR spectrum shows signs of great interest: the aromatic zone is observed between 1600 cm-1-1400 cm-1, characteristic signal of the aromatic aldehydes (C = O) at 1700 cm-1, aromatic alkenes (C = O) at 1300 cm-1 with overlapping signals -CH, = CH, additional a fourth signal very wide between 3400-2400cm-1 assigned to -OH. SEM micrographs show homogeneity on the surface. The TGA thermogram, a material loss is observed at 180 ° C of approximately 5% and another at 252 °C of 10%. Finally, the DSC thermogram is observed around 50 to 70 °C, a slight and wide change allows us to believe that this is the glass transition zone of the material, and a peak was found around 52.07 °C, where proposes that the degradation of the formulation occurs. As future work, biocompatibility and degradation tests will be carried out. Key words: Bone fractures; Films; PLGA/HAp; Physicochemical characterization.

Drug discovery is the process by which new candidate drugs are discovered. The chemical compounds that are present in plants and animals have been an important source of new bioactive compounds. Also, we can found organisms that live in air, water and soil that we don`t see, but posses a great variety of chemical that we can use to create new medicines. Bioactive compounds offer an enormous diversity of chemical structures with strong biolog‐ ic effect; this is one of the reasons why natural products research cannot be replaced by syn‐ thesis chemistry as a source for new bioactive compounds. Actually, more than the half of currently used medicines came from natural sources or are related to them, specifically in the situation of anticancer drugs that more than 60% belongs from nature [1].