In recent decades, significant advances in drug‐delivery systems have enabled more effective drug administration. To deliver drugs to specific organs, a range of organic systems (e.g., micelles, liposomes, and polymeric nanoparticles) have been designed. They suffer from limitations, including poor thermal and chemical stability, and rapid elimination by the immune system. In contrast, silica particles offer a biocompatible, stable, and “stealthy” alternative. Bioactive molecules can be easily encapsulated within silica particles by combining sol–gel polymerization with either spray‐drying or emulsion chemistry. Spray‐drying faces challenges, including low yield, surface segregation, and size limitations. In contrast, sol–gel emulsions enable the production of nanoparticles with homogeneous drug distribution, and permit ambient temperature processing, necessary for handling biologicals. Independent control of the size and release rate can be readily achieved. Preliminary in‐vivo experiments reveal enhanced blood stability of the nanoparticles, which, coupled with sustained release of anti‐tumor agents, show good potential for cancer treatment.

Polytetrafluoroethylene (PTFE) has been used for many years in different application fields 2 due to its outstanding chemical and physical properties. But, the value of its glass transition 3 temperature is still today a matter of controversy and very different values are proposed in the 4 literature. This paper proposes to answer to this scientific question using dynamic mechanical 5 measurements. First, the viscoelastic properties of PTFE are described on a large temperature 6 range and the influence of the shearing frequency is carefully investigated. Then, the effects 7 produced by the polymer annealing on its thermomechanical behavior are detailed. This study 8 comforts the idea that PTFE amorphous phase should be considered as comprised of two 9 distinct regions. The first one named "mobile amorphous fraction" (MAF) is able to relax at 10 low temperature (T =-103 °C). The other one is specific of the macromolecular segments 11 present at the boundaries between crystalline and amorphous domains. Due to the close 12 vicinity of the crystallites, these macromolecular segments present a more restricted mobility. 13 The corresponding phase is designated as the "rigid amorphous fraction" (RAF) and its 14 mechanical relaxation produces itself at higher temperature (T = 116 °C). Actually, this latter 15 value is strongly dependent on the material crystallinity degree. In particular, it is shifted to 16 higher temperature after occurrence of a recrystallization that is accompanied by a further 17 reduction of the RAF's dynamic. Instead, the characteristics of the MAF relaxation are poorly 18 affected. Tensile tests also support that the "real" T g of the polymer is located at low 19 temperature. All these results have been compared to those of the literature to propose a real 20 scientific discussion and to understand the origin of somewhat contradictory interpretations.