It is now well recognized that the production of petroleum-based packaging materials has created serious ecological problems for the environment due to their resistance to biodegradation. In this context, substantial research efforts have been made to promote the use of biodegradable films as sustainable alternatives to conventionally used packaging materials. Among several biopolymers, poly(lactide) (PLA) has found early application in the food industry thanks to its promising properties and is currently one of the most industrially produced bioplastics. However, more efforts are needed to enhance its performance and expand its applicability in this field, as packaging materials need to meet precise functional requirements such as suitable thermal, mechanical, and gas barrier properties. In particular, improving the mass transfer properties of materials to water vapor, oxygen, and/or carbon dioxide plays a very important role in maintaining food quality and safety, as the rate of typical food degradation reactions (i.e., oxidation, microbial development, and physical reactions) can be greatly reduced. Since most reviews dealing with the properties of PLA have mainly focused on strategies to improve its thermal and mechanical properties, this work aims to review relevant strategies to tailor the barrier properties of PLA-based materials, with the ultimate goal of providing a general guide for the design of PLA-based packaging materials with the desired mass transfer properties.

Fibre-based oral drug delivery systems are an attractive approach to addressing low drug solubility, although clear strategies for incorporating such systems into viable dosage forms have not yet been demonstrated. The present study extends our previous work on drug-loaded sucrose microfibres produced by centrifugal melt spinning to examine systems with high drug loading and investigates their incorporation into realistic tablet formulations. Itraconazole, a model BCS Class II hydrophobic drug, was incorporated into sucrose microfibres at 10, 20, 30, and 50% w/w. Microfibres were exposed to high relative humidity conditions (25 °C/75% RH) for 30 days to deliberately induce sucrose recrystallisation and collapse of the fibrous structure into powdery particles. The collapsed particles were successfully processed into pharmaceutically acceptable tablets using a dry mixing and direct compression approach. The dissolution advantage of the fresh microfibres was maintained and even enhanced after humidity treatment for drug loadings up to 30% w/w and, importantly, retained after compression into tablets. Variations in excipient content and compression force allowed manipulation of the disintegration rate and drug content of the tablets. This then permitted control of the rate of supersaturation generation, allowing the optimisation of the formulation in terms of its dissolution profile. In conclusion, the microfibre-tablet approach has been shown to be a viable method for formulating poorly soluble BCS Class II drugs with improved dissolution performance.

Oxidative stress is often the cause of a wide range of human chronic pathologies including, but not limited to, stroke and cardiovascular and neurodegenerative diseases. In this setting, increasing efforts are currently being devoted to the design and synthesis of new derivatives with enhanced antioxidant efficacy. Among all the potential molecules of interest, synthetic nitrone spin-traps have attracted a great deal of research attention, particularly due to their dual function as effective inhibitors of oxidative stress and damage and as analytical tools for the detection and characterization of free radicals by means of the electron paramagnetic resonance (EPR) spectroscopy spin trapping technique. In this study, two derivatives of benzoxazinic nitrones (3-aryl-2H-benzo[1,4]oxazin-N-oxides) bearing an electron-withdrawing methyl-acetate group on the benzo moiety (in para and meta positions with respect to the nitronyl function) were synthesized. Their in vitro antioxidant activity was evaluated by means of the α,α-diphenyl-β-picrylhydrazyl radical (DPPH) scavenging assay, and their inhibitory effects on the erythrocyte hemolysis induced by the water-soluble free radical initiator 2,2′-azobis(2-amidinopropane) dihydrochloride (AAPH) compared. In addition, EPR was employed to monitor the decay profiles of DPPH to evaluate the kinetic behavior of the different antioxidants tested. Results showed that the presence and the position of the electron-withdrawing methyl-acetate group strongly affects the radical scavenging activity of nitrones. In particular, the newly synthesized para-substituted derivative, when compared to both the meta-substituted isomer and the unsubstituted parent compound, acts as a more effective antioxidant both in cell and cell-free systems. Overall, these results clearly show that the introduction of an electron-withdrawing group on the phenyl moiety significantly increased the antioxidant capacity of benzoxazinic nitrones, thus showing exciting opportunities in the search for new therapeutic agents in the treatment of diseases associated with oxidative stress.