A protocol for preparation of polymer hydrogel spherical particles on a nanometer scale (nanogels) was developed. The protocol includes encapsulation of hydrogel-forming components into liposomes, UV-induced polymerization within the liposomes, solubilization of the lipid bilayer by detergent, removal of the phospholipid, detergent molecules, and their micelles by dialysis, and drying nanogels by evaporation in a temperature gradient. Dynamic light scattering technique was employed to characterize the size distribution of poly(acrylamide), poly(N-isopropylacrylamide), and poly(N-isopropylacrylamide-co-1-vinylimidazole) hydrogel particles. Hydrophobic chains of N-octadecylacrylamide were immobilized onto the surface of the poly(N-isopropylacrylamide-co-1-vinylimidazole) hydrogel particles to use them as anchors for attaching the nanogels onto the lipid bilayers. The diameter of the nanogels prepared varied between 30 and 300 nm. The solvent, temperature, and pH sensitivities of the liposomes, nanogels, and...