Strikingly, Kraft lignin nanoparticles (KLNPs) can substitute polluting nanoparticles in diverse applications. An attractive method for synthesizing KLNPs is Solvent shifting. We hypothesized that by a detailed understanding of the solvent properties and influence of the process parameters, one could derive new fundamental and technical information about the lignin nanoparticle formation process. DMSO and THF were chosen best solvents based on the Hansen solubility parameter of lignin. The four synthesis parameters such as lignin concentration, (anti-solvent) water volume, temperature, and stirring speed were used to investigate the size, polydispersity index (PDI), morphology as well as the thermal, mechanical and optical properties of KLNPs_DMSO & KLNPs_THF. KLNPs_THF follows the well-known nucleation and growth (NG) mechanism, resulting in spherical KLNPs (43 ± 12 nm: 0.20 PDI). Surprisingly, KLNPs_DMSO follows a unique mechanism resembling spinodal decomposition (SD), which generates rare bicontinuous-to-spherical KLNPs (17 ± 8 nm: 0.20 PDI). Remarkably, we show that the difference in the KLNPs mechanism modulates their intrinsic properties, such as glass transition temperature (Tg), specific surface area (SSA), elastic modulus (EM) and optical properties. Beyond the new mechanism, our synthesis resulted in reproducible ultra-small KLNPs with an excellent % yield. Such findings have vast implications in high-performance nanocomposites.

In silica-rubber based nanocomposites, a single organo-silicon is often used to compatibilize and covalently link silica to rubber. In this work, we have investigated the impact, at micro- and macroscales, of the decoupling of the hydrophobization and the coupling activity of silane by pretreating silica with two different silane chemistries. The first one, a mercaptosilane, is the coupling agent that promotes a covalent link between silica and rubber during the sulfur-mediated vulcanization reaction. The second one, an alkylsilane, aims to improve the silica dispersion. For both kind of silanes, we have varied the chain length and studied at macroscale the dynamic mechanical properties through the key indicators that are E'' as loss modulus, E' as storage modulus, and their respective ratio tan δ. The shorter silanes combination yielded an improvement in terms of wet grip indicators with tan δ at 0 °C increasing from 0.205 to 0.237 while maintaining rolling resistance indicators at the same level. We have evaluated the impact of the silane chemistry onto the cross-linking reactivity within the fabricated rubber-based nanocomposites by using moving-dye rheometer measurements (MDR). By purposely using atomic force microscopy (AFM), we have studied the silica dispersion in the matrix and the rubber/silica interface and provided the rationale explanation of the mechanical properties observed at the macroscale. AFM observation pointed out the existence of a soft interface around silica fillers when long alkylsilanes were used. We infer that this interface impacts the polymer-filler dynamic and subsequently affects the mechanical properties of the composite material.

Photosensitizers are used in photodynamic therapy (PDT) to destruct tumor cells, however, their limited solubility and specificity hampers routine use, which may be overcome by encapsulation. Several promising novel nanoparticulate drug carriers including liposomes, polymeric nanoparticles, metallic nanoparticles and lipid nanocomposites have been developed. However, many of them contain components that would not meet safety standards of regulatory bodies and due to difficulties of the manufacturing processes, reproducibility and scale up procedures these drugs may eventually not reach the clinics. Recently, we have designed a novel lipid nanostructured carrier, namely Lipidots, consisting of nontoxic and FDA approved ingredients as promising vehicle for the approved photosensitizer m-tetrahydroxyphenylchlorin (mTHPC). In this study we tested Lipidots of two different sizes (50 and 120 nm) and assessed their photodynamic potential in 3-dimensional multicellular cancer spheroids. Microscopically, the intracellular accumulation kinetics of mTHPC were retarded after encapsulation. However, after activation mTHPC entrapped into 50 nm particles destroyed cancer spheroids as efficiently as the free drug. Cell death and gene expression studies provide evidence that encapsulation may lead to different cell killing modes in PDT. Since ATP viability assays showed that the carriers were nontoxic and that encapsulation reduced dark toxicity of mTHPC we conclude that our 50 nm photosensitizer carriers may be beneficial for clinical PDT applications.

New understandings in the amorphous calcium carbonate nanoparticle synthesis lead to a final mass concentration increase by a factor of 3.5. The stabilisation in aqueous media is achieved by a 2-minute scalable process using bio-sourced stabilisers.