Interpenetrating alginate network as drug delivery matrix: Effects on protein stability and release.

The study investigates the rheological properties and protein release capacity of a uniform hydrogel composed of sodium alginate (SA) and poloxamer (P407). The hydrogel is prepared through the sustained release of calcium ions, resulting in a reinforced and homogeneous interpenetrating networks (IPNs) of SA and P407 polymeric chains. By adjusting the amount of crosslink agent, the hydrogel exhibites an adjustable dissolution ratio and adaptable gelling time. Moreover, the composite showed a well-structured network and superior mechanical strength, enabling the sustained release of both calcium ions and Soybean Trypsin Inhibitor (STI) protein, a model of Bone Morphogenic Protein (BMP). Importantly, the protein release kinetic can be tuned based on the SA content in the polymeric blend, highlighting the versatile nature of this hydrogel for drug delivery purposes.

Biodegradable Microparticles for Regenerative Medicine: A State of the Art and Trends to Clinical Application.

Tissue engineering and cell therapy are very attractive in terms of potential applications but remain quite challenging regarding the clinical aspects. Amongst the different strategies proposed to facilitate their implementation in clinical practices, biodegradable microparticles have shown promising outcomes with several advantages and potentialities. This critical review aims to establish a survey of the most relevant materials and processing techniques to prepare these micro vehicles. Special attention will be paid to their main potential applications, considering the regulatory constraints and the relative easiness to implement their production at an industrial level to better evaluate their application in clinical practices.

Efficient antibacterial nanosponges based on ZnO nanoparticles and doxycycline.

Bacterial soft rot is responsible for the loss of about 25% of worldwide production in vegetables and fruits. Efforts have been made to develop an effective nanosponge with the capacity to load and release antibacterial drugs to protect plants. Based on the potential of the ZnO nanoparticles (ZnO-NPs) to achieve this goal, this study synthesized NP via the sol-gel and hydrothermal methods by controlling native defects, such as oxygen vacancies, using thermal treatments and reduced atmospheres. To characterize the ZnO NPs, X-ray diffraction (XRD), Raman spectroscopy, transmission electron microscopy (TEM), optical spectroscopy, electron paramagnetic resonance (EPR), Zeta Potential measurements and surface area with the Brunauer-Emmett-Teller (BET) method were used. The photophysical and photochemical properties via spin trapping method aligned with EPR using UVA light showed a greater formation of electron-hole pairs and hydroxyl radicals for the reduced ZnO NPs when compared with the oxidized ones. Additionally, we found that reduced ZnO-NPs have high effectively against Escherichia coli, Erwinia carotovora and Pantoea sp. bacteria using the photocatalytic effect in the UV range. Moreover, ZnO-NPs loaded with DOX release profile enables the release of DOX within 46days, where 25% was released during the first 10h followed by a second delivery phase with an interesting short-term efficacy (<1day) against E. carotovora and Pantoea sp. Bacteria. For the first time, it was demonstrated that ZnO-NPs and ZnO-NPs loaded with DOX have efficient UV photocatalytic activities against bacterial soft rot infections.

Magnetic nanoparticles coated with cyclodextrins and citrate for irinotecan delivery.

In the present work, we study the role of different components in the formation of more stable iron oxide magnetic nanoparticles (MNPs): ß-cyclodextrin (BCD), 2-hydroxypropyl-ß-cyclodextrin (HP) and citrate anion. MNPs formulations were characterized by FTIR, particles size measurements, zeta potential based on dynamic light scattering principle technique, X-ray powder pattern diffraction, XPS spectroscopy, transmission electron microscopy and thermogravimetric analysis. The results showed that cyclodextrins and citrate plays a key role in order to obtain a lower size of coated MNPs and proved to be an efficient strategy to obtain a more stable colloidal dispersion, avoiding the nanoparticles oxidation, enhancing the irinotecan incorporation and release. Furthermore, citrate-coated BCD-MNPs showed the same cytotoxicity of the free IRI.

Nanofibers containing tetracycline/ß-cyclodextrin: Physico-chemical characterization and antimicrobial evaluation.

This study aimed to compare two nanofiber drug delivery systems that were prepared with an electrospun process and have the potential to serve as adjuvants for the treatment of periodontal disease. The first system was composed of polycaprolactone loaded with tetracycline (TCN) and the second was composed of polycaprolactone loaded with tetracycline/ß-cyclodextrin (TCN:BCD). An antimicrobial diffusion test was performed for each of these sets of nanofibers with the microorganisms, Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis, both of which contribute to periodontal disease. In vitro release profiles were also obtained, and the nanofibers were characterized by thermal analysis, x-ray powder diffraction, infrared absorption spectroscopy, and scanning electron microscopy. Profiles of the TCN and TCN:BCD nanofibers showed that drug release occurred for up to 14days. However, the TCN:BCD nanofibers appeared to better protect and enhance the biological absorption of TCN due to the formation of a TCN:BCD inclusion complex.