Polymeric microparticles (MPs) are recognized as very popular carriers to increase the bioavailability and bio-distribution of both lipophilic and hydrophilic drugs. Among different kinds of polymers, poly-(lactic-co-glycolic acid) (PLGA) is one of the most accepted materials for this purpose, because of its biodegradability (due to the presence of ester linkages that are degraded by hydrolysis in aqueous environments) and safety (PLGA is a Food and Drug Administration (FDA)-approved compound). Moreover, its biodegradability depends on the number of glycolide units present in the structure, indeed, lower glycol content results in an increased degradation time and conversely a higher monomer unit number results in a decreased time. Due to this feature, it is possible to design and fabricate MPs with a programmable and time-controlled drug release. Many approaches and procedures can be used to prepare MPs. The chosen fabrication methodology influences size, stability, entrapment efficiency, and MPs release kinetics. For example, lipophilic drugs as chemotherapeutic agents (doxorubicin), anti-inflammatory non-steroidal (indomethacin), and nutraceuticals (curcumin) were successfully encapsulated in MPs prepared by single emulsion technique, while water-soluble compounds, such as aptamer, peptides and proteins, involved the use of double emulsion systems to provide a hydrophilic compartment and prevent molecular degradation. The purpose of this review is to provide an overview about the preparation and characterization of drug-loaded PLGA MPs obtained by single, double emulsion and microfluidic techniques, and their current applications in the pharmaceutical industry. Graphic abstract

Neurodegenerative diseases are often caused by uncontrolled amyloid aggregation. Hence, many drug discovery processes are oriented to evaluate new compounds that are able to modulate self-recognition mechanisms. Herein, two related glycoconjugate pentacoordinate Pt­(II) complexes were analyzed in their capacity to affect the self-aggregation processes of two amyloidogenic fragments, Aβ21–40 and Aβ25–35, of the C-terminal region of the β-amyloid (Aβ) peptide, the major component of Alzheimerʼs disease (AD) neuronal plaques. The most water-soluble complex, 1Pt dep , is able to bind both fragments and to deeply influence the morphology of peptide aggregates. Thioflavin T (ThT) binding assays, electrospray ionization mass spectrometry (ESI-MS), and ultraviolet–visible (UV–vis) absorption spectroscopy indicated that 1Pt dep shows different kinetics and mechanisms of inhibition toward the two sequences and demonstrated that the peptide aggregation inhibition is associated with a direct coordinative bond of the compound metal center to the peptides. These data support the in vitro ability of pentacoordinate Pt­(II) complexes to inhibit the formation of amyloid aggregates and pave the way for the application of this class of compounds as potential neurotherapeutics.

In recent years, drug delivery systems have become some of the main topics within the biomedical field. In this scenario, polymeric microparticles (MPs) are often used as carriers to improve drug stability and drug pharmacokinetics in agreement with this kind of treatment. To avoid a mere and time-consuming empirical approach for the optimization of the pharmacokinetics of an MP-based formulation, here, we propose a simple predictive in silico-supported approach. As an example, in this study, we report the ability to predict and tune the release of curcumin (CUR), used as a model drug, from a designed combination of different poly(d,l-lactide-co-glycolide) (PLGA) MPs kinds. In detail, all CUR–PLGA MPs were synthesized by double emulsion technique and their chemical–physical properties were characterized by Mastersizer and scanning electron microscopy (SEM). Moreover, for all the MPs, CUR encapsulation efficiency and kinetic release were investigated through the UV–vis spectroscopy. This approach, based on the combination of in silico and experimental methods, could be a promising platform in several biomedical applications such as vaccinations, cancer-treatment, diabetes therapy and so on.

Polymeric microneedles (MNs) have emerged as a novel class of drug delivery system thanks to their ability in penetrating the skin with no pain, encapsulate active proteins and in particular, proposed bicompartimental MNs can tune protein release.

Introduction CoenzymeQ 10 (CoQ 10 ) is a well-known antioxidant and anti-inflammatory agent with cardioprotective properties. However, clinical trials based on its oral administration have failed to provide significant effect on cardiac functionality. The main limitation of CoQ 10 is based on its very low oral bioavailability and instability that limit dramatically its effects as a cardioprotective agent. Herein, we loaded CoQ 10 in high bioavailable nano-emulsions (NEs) coated with chitosan or chitosan and hyaluronic acid in order to improve its performance. Methods We tested cardioprotective and hepatoprotective effects of CoQ 10 -loaded nano-carriers against Doxorubicin and Trastuzumab toxicities in cardiomyocytes and liver cells through analysis of cell viability, lipid peroxidation, expression of leukotrienes, p65/NF-kB and pro-inflammatory cytokines involved in anticancer-induced cardio and hepatotoxicity. Results Nano-carriers showed high stability and loading ability and increased cell viability both in hepatocytes and cardiomyocytes during anticancer treatments. We observed that these effects are mediated by the inhibition of lipid peroxidation and reduction of the inflammation. CoQ 10 -loaded nano-emulsions showed also strong anti-inflammatory effects reducing leukotriene B4 and p65/NF-κB expression and Interleukin 1β and 6 production during anticancer treatments. Discussion Anthracyclines and Human epidermal growth factor receptor (HER2) inhibitors have shown significant anticancer effects in clinical practice but their use is characterized by cardiotoxicity and hepatotoxicity. Nano-carriers loaded with CoQ 10 showed cardio and hepatoprotective properties mediated by reduction of oxidative damages and pro-inflammatory mediators. These results set the stage for preclinical studies of cardio and hepatoprotection in HER2+ breast cancer-bearing mice treated with Doxorubicin and Trastuzumab.

Recently, we developed ultra-stable oil in water nano-emulsions (O/W NEs), able to carry both internal and external cargos (Somes), such as lipophilic compounds and hydrophilic coatings, respectively, that we call here NEsoSomes. O/W NEs are an excellent bioengineering tool for drug and molecules delivery, due to their ability to dissolve a large number of hydrophobic compounds and protect them from hydrolysis and degradation under biological conditions. At present, no report is available on the combination of cell membrane coatings with such nanocarriers, probably due to their typical instability feature. Since then, we have reported, for the first time, a new cell membrane (CM)-coated nanomaterial composed of membranes extracted from glioblastoma cancer cells (U87-MG) deposited on NEsoSomes, through a liquid–liquid interface method, to produce highly controllable membrane caked nano-capsules, namely CM-NEsoSomes. CM-NEsoSomes were physically characterized by dynamic light scattering (DLS) over time and their correct morphology was analyzed by confocal and transmission electron microscopy (TEM) microscopy. Moreover, CM-NEsoSomes biocompatibility was tested on the healthy model cell line, performing cell cytotoxicity and uptake assay, showing nanocarriers uptake by cells with no induced cytotoxicity.

The intestinal microbiota is a real ecosystem composed of several bacterial species and a very huge amount of strains that through their metabolic activities play a crucial role in the development and performance of the immune system and other functions. Microbiota modulation by probiotics establishes a new era into the pharmaceutical and healthcare market. Probiotics play, in fact, an important role in helping and sustaining human health, but in order to produce benefits, their viability must be preserved throughout the production process up to consumption, and in addition, their bioactivity required to be safeguarded while passing through the gastrointestinal tract. In this frame, encouraging results come from encapsulation strategies that have proven to be very promising in protecting bacteria and their viability. However, specific effort has to be dedicated to the design optimization of the encapsulation process and, in particular, to the processing parameters that affect capsules microstructure. Herein, focusing on calcium alginate microspheres, after a preliminary selection of their processing conditions based on size distribution, we implemented a micro-rheological analysis, by using the multiple-particle tracking technique, to correlate the inner microstructure to the selected process conditions and to the viability of the Lactobacillus paracasei CBA L74. It was assessed that the explored levels of cross-linking, although changing the microorganism constriction, did not affect its viability. The obtained results confirm how this technology is a promising and a valid strategy to protect the microorganism viability and ensure its stability during the production process.

The study of novel drug delivery systems represents one of the frontiers of the biomedical research area. Multi-disciplinary scientific approaches combining traditional or engineered technologies are used to provide major advances in improving drug bioavailability, rate of release, cell/tissue specificity and therapeutic index. Biodegradable and bio-absorbable polymers are usually the building blocks of these systems, and their copolymers are employed to create delivery components. For example, poly (lactic acid) or poly (glycolic acid) are often used as bricks for the production drug-based delivery systems as polymeric microparticles (MPs) or micron-scale needles. To avoid time-consuming empirical approaches for the optimization of these formulations, in silico-supported models have been developed. These methods can predict and tune the release of different drugs starting from designed combinations. Starting from these considerations, this review has the aim of investigating recent approaches to the production of polymeric carriers and the combination of in silico and experimental methods as promising platforms in the biomedical field.