FRAME, with its rapid photopolymerization and fine mesh size, effectively preserves the structural integrity of non-equilibrium colloidal assemblies. It is important to acknowledge that, given the inherently non-equilibrium nature of these systems, the structure captured by FRAME represents a snapshot of a specific arrangement of the assembly. To fully understand the range of configurations occurring dynamically, multiple samples would need to be immobilized and analysed according to the ergodic hypothesis.REF Despite this, FRAME significantly simplifies the characterization of non-equilibrium self-assemblies using high-resolution imaging techniques. Additionally, because the hydrogel used is fully transparent and has a refractive index similar to that of water (indicate here the refractive index that I calculated in Barcelona vs 1.334, respectively), spectroscopic methods are also applicable. While our focus has been on imaging and structural analysis, this FRAME is versatile and can be integrated with a variety of other characterization techniques.