Provided herein are compositions of functionalized, fluorescent nanocrystals comprising fluorescent nanocrystals coated with an imidazole-containing compound; compositions of functionalized, fluorescent nanocrystals comprising fluorescent nanocrystals coated with an imidazole-containing compound and cross-linked with a phosphine cross-linking compound; compositions of functionalized fluorescent nanocrystals operably bound to molecular probe; a process of making functionalized, fluorescent nanocrystals; and a process of using functionalized, fluorescent nanocrystals in a detection system.