Finally, the selective binding of GFP to the antibody produced a uniform fluorescent corona around the islets. Cell encapsulation in hydrogels or porous matrices has been widely investigated in tissue-engineering applications [14]. Polysaccharide-based hydrogels, such as alginate, chitosan, and dextran, or proteins such as collagen, silk, and elastin are the components most commonly explored to date [15; 16; 17]. Among them, chitosan plays a key role. In this Special Issue, two contributions exploited this polymer for different purposes. [PERSON] et al. developed an injectable form of chitosan for in situ hydrogel formation for tissue engineering. The addition of salts, such as beta-glycerol phosphate and sodium hydrogen carbonate, allowed them to obtain stable and biocompatible formulations, which gelled under physiological conditions at 37 \({}^{\circ}\)C. This study aimed to realize hydrogels with high swelling ratios and mechanical stiffnesses suitable for cell encapsulation [18]. In another study, by [PERSON] et al., chitosan was used to obtain microparticles, through the ionic gelation method, for the encapsulation of glibenclamide (Gly) and lipoic acid (LA). These two compounds, an antidiabetic that stimulates insulin production and an antioxidant, respectively, are used in the management of diabetes mellitus. The entrapment efficiency was very high for Gly, with a high percentage release efficiency for both drugs. The swelling data showed a fine behavior in simulated gastric fluid, suggesting potential for the preparations to be used with oral administration [19]. From the cell level to the nano- and microparticle levels, the techniques of encapsulation have rapidly evolved in the last few years, from simple polymer shells to more sophisticated stimulus-responsive coatings or multiple layers with tunable chemical/biological affinity. Inorganic materials such as silica have also been considered. Indeed, silica facilitates several synthetic strategies and is very well suited to the controlled encapsulation of inorganic nanoparticles, for the protection of the core or to increase the system biocompatibility. [PERSON] et al. showed how the introduction of giant quantum dots (GQDs), namely, organic capped PbS@CdS@CdS, in a silica shell allowed the exploitation of their optical properties for temperature monitoring. Through a microemulsion process, the GQDs were individually encapsulated in a silica shell of 10-15 nm. Temperature variations influence the ratio between the two integrated PbS and CdS emission bands of GQDs. This peculiarity was also maintained after silica shell growth, with a ratiometric response (\(\mathrm{I_{PoS}}/\mathrm{I_{CdS}}\)) that monotonically decreased with the temperature, with a sensitivity of 0.01 K\({}^{-1}\)[20]. [PERSON] and [PERSON] et al. investigated the contribution of a silica shell in the hyperthermia profiles of maghemite nanoparticles. These magnetic nanoparticles could be used as heating agent through magnetic hyperthermia or laser-assisted photothermal, exploiting different mechanisms. The study demonstrated that the encapsulation of the nanoparticles in the shell enhanced the heating performance in photothermal, due to the increased thermal conductivity of the fluid. For magnetic hyperthermia, the suppression of the Brownian relaxation (which reduced the hyperthermia efficiency in other studies) was counterbalanced by the faster heat dissipation of the silica shell, resulting in comparable heating outcomes between individual nanoparticles and silica-encapsulated ones [21]. Finally, it is worth mentioning the review by [PERSON] and [PERSON] that analyzed the implications of using chiral molecules as surface coatings for nanoparticles and the recent applications of chiral nanoparticles in four major research fields: enantioselective recognition, asymmetric catalysis, biomedicine, and biosensing [22].