The present invention provides a conjugate comprising: (a) a CNS-targeting ligand, (b) a hydrophilic polymer of polyethylene glycol (PEG), polylactic acid (PLA), polylactic-co-glycolic acid (PLGA), or dextran, and (c) a flavonoid. The present invention also provides to a micelle nanoparticle composition comprising: (a) an outer shell comprising the conjugate, optionally (b) an inner shell comprising oligomeric (-)-epigallocatechin gallate (OEGCG), and optionally (c) a CNS disease-treating molecule encapsulated in the inner shell. The present invention further provides a method for treating a CNS disease by administering an effective amount of the present nanoparticle composition to a subject. The CNS-targeting ligand targets the CNS tissue and delivers active ingredients to CNS tissue for treating the CNS pathogenic conditions.