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Being designated to protect other tissues, skin is the first and largest human body organ to be injured and for this reason, it is accredited with a high capacity for self-repairing. However, in the case of profound lesions or large surface loss, the natural wound healing process may be ineffective or insufficient, leading to detrimental and painful conditions that require repair adjuvants and tissue substitutes. In addition to the conventional wound care options, biodegradable polymers, both synthetic and biologic origin, are gaining increased importance for their high biocompatibility, biodegradation, and bioactive properties, such as antimicrobial, immunomodulatory, cell proliferative, and angiogenic. To create a microenvironment suitable for the healing process, a key property is the ability of a polymer to be spun into submicrometric fibers (e.g., via electrospinning), since they mimic the fibrous extracellular matrix and can support neo- tissue growth. A number of biodegradable polymers used in the biomedical sector comply with the definition of bio-based polymers (known also as biopolymers), which are recently being used in other industrial sectors for reducing the material and energy impact on the environment, as they are derived from renewable biological resources. In this review, after a description of the fundamental concepts of wound healing, with emphasis on advanced wound dressings, the recent developments of bio-based natural and synthetic electrospun structures for efficient wound healing applications are highlighted and discussed. This review aims to improve awareness on the use of bio-based polymers in medical devices.

Environmental impacts and consumer concerns have necessitated the study of bio-based materials as alternatives to petrochemicals for packaging applications. The purpose of this review is to summarize synthetic and non-synthetic materials feasible for packaging and textile applications, routes of upscaling, (industrial) applications, evaluation of sustainability, and end-of-life options. The outlined bio-based materials include polylactic acid, polyethylene furanoate, polybutylene succinate, and non-synthetically produced polymers such as polyhydrodyalkanoate, cellulose, starch, proteins, lipids, and waxes. Further emphasis is placed on modification techniques (coating and surface modification), biocomposites, multilayers, and additives used to adjust properties especially for barriers to gas and moisture and to tune their biodegradability. Overall, this review provides a holistic view of bio-based packaging material including processing, and an evaluation of the sustainability of and options for recycling. Thus, this review contributes to increasing the knowledge of available sustainable bio-based packaging material and enhancing the transfer of scientific results into applications.

Chitin and lignin, by-products of fishery and plant biomass, can be converted to innovative high value bio- and eco-compatible materials. On the nanoscale, high antibacterial, anti-inflammatory, cicatrizing and anti-aging activity is obtained by controlling their crystalline structure and purity. Moreover, electropositive chitin nanofibrlis (CN) can be combined with electronegative nanolignin (NL) leading to microcapsule-like systems suitable for entrapping both hydrophilic and lipophilic molecules. The aim of this study was to provide morphological, physico-chemical, thermogravimetric and biological characterization of CN, NL, and CN-NL complexes, which were also loaded with glycyrrhetinic acid (GA) as a model of a bioactive molecule. CN-NL and CN-NL/GA were thermally stable up to 114 °C and 127 °C, respectively. The compounds were administered to in vitro cultures of human keratinocytes (HaCaT cells) and human mesenchymal stromal cells (hMSCs) for potential use in skin contact applications. Cell viability, cytokine expression and effects on hMSC multipotency were studied. For each component, CN, NL, CN-NL and CN-NL/GA, non-toxic concentrations towards HaCaT cells were identified. In the keratinocyte model, the proinflammatory cytokines IL-1α, IL-1 β, IL-6, IL-8 and TNF-α that resulted were downregulated, whereas the antimicrobial peptide human β defensin-2 was upregulated by CN-LN. The hMSCs were viable, and the use of these complexes did not modify the osteo-differentiation capability of these cells. The obtained findings demonstrate that these biocomponents are cytocompatible, show anti-inflammatory activity and may serve for the delivery of biomolecules for skin care and regeneration.

The synergistic effect of nucleating agents and plasticizers on the thermal and mechanical performance of PLA nanocomposites was investigated with the objective of increasing the crystallinity and balancing the stiffness and toughness of PLA mechanical properties. Calcium carbonate, halloysite nanotubes, talc and LAK (sulfates) were compared with each other as heterogeneous nucleating agents. Both the DSC isothermal and non-isothermal studies indicated that talc and LAK were the more effective nucleating agents among the selected fillers. Poly(D-lactic acid) (PDLA) acted also as a nucleating agent due to the formation of the PLA stereocomplex. The half crystallization time was reduced by the addition of talc to about 2 min from 37.5 min of pure PLA by the isothermal crystallization study. The dynamic mechanical thermal study (DMTA) indicated that nanofillers acted as both reinforcement fillers and nucleating agents in relation to the higher storage modulus. The plasticized PLA studied by DMTA indicated a decreasing glass transition temperature with the increasing of the PEG content. The addition of nanofiller increased the Young’s modulus. PEG had the plasticization effect of increasing the break deformation, while sharply decreasing the stiffness and strength of PLA. The synergistic effect of nanofillers and plasticizer achieved the balance between stiffness and toughness with well-controlled crystallization.

In this work poly(lactic) acid (PLA)/poly(butylene succinate-co-adipate) (PBSA) biobased binary blends were investigated. PLA/PBSA mixtures with different compositions of PBSA (from 15 up to 40 wt.%) were produced by twin screw-extrusion. A first screening study was performed on these blends that were characterized from the melt fluidity, morphological and thermo-mechanical point of view. Starting from the obtained results, the effect of an epoxy oligomer (EO) (added at 2 wt.%) was further investigated. In this case a novel approach was introduced studying the micromechanical deformation processes by dilatometric uniaxial tensile tests, carried out with a videoextensometer. The characterization was then completed adopting the elasto-plastic fracture approach, by the measurement of the capability of the selected blends to absorb energy at a slow rate. The obtained results showed that EO acts as a good compatibilizer, improving the compatibility of the rubber phase into the PLA matrix. Dilatometric results showed different micromechanical responses for the 80–20 and 60–40 blends (probably linked to the different morphology). The 80–20 showed a cavitational behavior while the 60–40 a deviatoric one. It has been observed that while the addition of EO does not alter the micromechanical response of the 60–40 blend, it profoundly changes the response of the 80–20, that passed to a deviatoric behavior with the EO addition.

Consumer awareness about the damages that plastic packaging waste cause to the environment, coupled with bio-economy and circular economy policies, are pushing plastic packaging versus the use of bio-based and biodegradable materials. In this contest, even cosmetic packaging is looking for sustainable solutions, and research is focusing on modifying bio-based and biodegradable polymers to meet the challenging requirements for cosmetic preservation, while maintaining sustainability and biodegradability. Several bio-based and biodegradable polymers such as poly(lactic acid), polyhydroxyalkanoates, polysaccharides, etc., are available, and some first solutions for both rigid and flexible packaging are already present on the market, while many others are under study and optimization. A fruitful cooperation among researchers and industries will drive the cosmetic sector toward being more ecological and contributing to save our environment.

In this work, biocomposites based on poly(lactic acid) (PLA) and short flax fibers (10–40 wt.%) were produced by extrusion and characterized in terms of thermal, mechanical, morphological, and thermo-mechanical properties. Analytical models were adopted to predict the tensile properties (stress at break and elastic modulus) of the composites, and to assess the matrix/fiber interface adhesion. The resulting composites were easily processable by extrusion and injection molding up to 40 wt.% of flax fibers. It was observed that despite any superficial treatment of fibers, the matrix/fiber adhesion was found to be sufficiently strong to ensure an efficient load transfer between the two components obtaining composites with good mechanical properties. The best mechanical performance, in terms of break stress (66 MPa), was obtained with 20 wt.% of flax fibers. The flax fiber acted also as nucleating agent for PLA, leading to an increment of the composite stiffness and, at 40 wt.% of flax fibers, improving the elastic modulus decay near the PLA glass transition temperature.

The intratumoral injection of cytokines, in particular IL2, has shown promise for cutaneous melanoma patients with unresectable disease or continuous recurrence despite surgery. We recently reported that the intralesional injection of L19-IL2, an immunocytokine combining IL2 and the human monoclonal antibody fragment L19, resulted in efficient regional control of disease progression, increased time to distant metastasis and evidence of effect on circulating immune cell populations. We have also shown in preclinical models of cancer a remarkable synergistic effect of the combination of L19-IL2 with L19-TNF, a second clinical-stage immunocytokine, based on the same L19 antibody fused to TNF. Here, we describe the results of a phase II clinical trial based on the intralesional administration of L19-IL2 and L19-TNF in patients with stage IIIC and IVM1a metastatic melanoma, who were not candidate to surgery. In 20 efficacy-evaluable patients, 32 melanoma lesions exhibited complete responses upon intralesional administration of the two products, with mild side effects mainly limited to injection site reactions. Importantly, we observed complete responses in 7/13 (53.8 %) non-injected lesions (4 cutaneous, 3 lymph nodes), indicating a systemic activity of the intralesional immunostimulatory treatment. The intralesional administration of L19-IL2 and L19-TNF represents a simple and effective method for the local control of inoperable melanoma lesions, with a potential to eradicate them or make them suitable for a facile surgical removal of the residual mass.

In the perspective of producing a rigid renewable and environmentally friendly rigid packaging material, two comb-like copolymers of cellulose acetate (AC) and oligo(lactic acid) OLA, feeding different percentages of oligo(lactic acid) segments, were prepared by chemical synthesis in solvent or reactive extrusion in the melt, using a diepoxide as the coupling agent and were used as compatibilizers for poly(lactic acid)/plasticized cellulose acetate PLA/pAC blends. The blends were extruded at 230 °C or 197 °C and a similar compatibilizing behavior was observed for the different compatibilizers. The compatibilizer C1 containing 80 wt% of AC and 14 wt% of OLA resulted effective in compatibilization and it was easily obtained by reactive extrusion. Considering these results, different PLAX/pAC(100-X) compounds containing C1 as the compatibilizer were prepared by extrusion at 197 °C and tested in terms of their tensile and impact properties. Reference materials were the uncompatibilized corresponding blend (PLAX/pAC(100-X)) and the blend of PLA, at the same wt%, with C1. Significant increase in Young’s modulus and tensile strength were observed in the compatibilized blends, in dependence of their morphologic features, suggesting the achievement of an improved interfacial adhesion thanks to the occurred compatibilization.

The toughening mechanisms of poly(lactic acid; PLA) blended with two different elastomers, namely poly (butylene adipate-co-terephtalate; PBAT) and polyolefin elastomers with grafted glycidyl methacrylate (POE-g-GMA), at 10 and 20 wt.%, were investigated. Tensile and Charpy impact tests showed a general improvement in the performance of the PLA. The morphology of the dispersed phases showed that PBAT is in the form of spheres while POE-g-GMA has a dual sphere/fibre morphology. To correlate the micromechanical deformation mechanism with the macroscopical mechanical behaviour, the analysis of the subcritical crack tip damaged zone of double-notched specimens subjected to a four-point bending test (according to the single-edge double-notch four-point bend (SEDN-4PB) technique) was carried out using several microscopic techniques (SEM, polarized TOM and TEM). The damage was mainly generated by shear yielding deformation although voids associated with dilatational bands were observed.