The present invention generally relates to colloidal systems, which may include colloidal particles and/or other types of particles. One aspect of the invention is generally directed to a system comprising fluidic droplets that can be at least partially solidified, e.g., to form colloidal particles. In some embodiments, particles comprising an at least partially solid outer phase encapsulating an inner phase are formed. The inner phase may be any phase, e.g., a solid, a liquid, or a gas. In some cases, solidifying at least a portion of the outer phase of the droplets to form particles may increase the stability of the particles and/or the colloidal system containing the particles. In one set of embodiments, melting or liquefying the outer phase of the particles (for example, by heating the particle to a temperature above a threshold temperature) can allow release of an agent contained within the inner phase, and/or allow the inner phase to coalesce with a phase external to the particles. The melting temperature of the outer phase can be controlled in some embodiments such that the outer phase will melt above a predetermined temperature. In some embodiments, the particles may be formed to be essentially free of an auxiliary stabilizing agent. In some embodiments, an agent may be encapsulated within a particle with relatively high efficiency. Other aspects of the invention are generally directed to methods of making and using such colloidal systems, e.g., containing such particles, kits involving such colloidal systems, or the like.La présente invention concerne en général des systèmes colloïdaux, pouvant comprendre des particules colloïdales et/ou dautres types de particules. Un aspect de linvention concerne en général un système comprenant des gouttelettes fluides qui peuvent être au moins partiellement solidifiées, par exemple, afin de former des particules colloïdales. Dans certains modes de réalisation, des particules sont formées, comprenant une phase externe au
