ABSTRACT
Two kinds of different functional groups modified RuBpy-doped silica fluorescent nanoprobes Probe A and B that conjugated with avidin were prepared for the recognition of liver cancer cells. Firstly RuBpy-doped silica nanoparticles were synthesized by reverse microemulsion and modified with different functional groups, then Probe A was prepared by the conjugation of avidin with carboxyl modified nanoparticles through covalent binding using 1-ethyl-3-( 3-dimethylamino propyl ) carbodiimide hydrochloride ( EDC )/sulfo-NHS, whereas Probe B was prepared by the conjugation of avidin with the polyethylene glycol ( PEG) linkers on the surface nanoparticles using cyanogen bromide method. Therefore, compared with Probe A, Probe B was obtained by coupling avidin to the nanoparticles through long-chain PEG molecules. The two probes were incubated with liver cancer cells respectively, and microscopic fluorescence imaging shows that Probe B which contained PEG molecules could be more effectively applied for the recognition of tumor marker carcinoembryonic antigen ( CEA) in liver cancer cells.