Surface modification of PCL-PEG-PCL nanoparticles (NPs) with beta-cycloclextrin (beta-CD) and other functional groups could enhance the therapeutic and targeting characteristics of NPs. In this report:, beta-CD grafted poly (acrylic acid) (PCDAA) polymer was synthesized by radical polymerization, and then embedded on the surface of polycaprolactone-poly(ethylene glycol) (PCL-PEG-PCL) NPs through host guest interaction and hydrogen bonding between oxygen of PEG and carboxyl group of PCDAA. These PCDAA embedded PCL-PEG-PCL (PCDAA@PCL-PEG-PCL) NPs showed a spherical core -shell structure and their size was less than 200 rim. The drug loading experiments described that these NPs had high drug loading capacity for PD( compared to the original PCL-PEG-PCL NPs It is likely that hydrophobic cavities of beta-CD also encapsulated some amount of drug along with its inner core which could enhance the drug loading capacity of these NPs. Moreover, PTX was released smoothly without remarkable initial burst release during the in vitro drug release experiments i.e. only 20% drug was released in first 12 Ii, which could be attributed to its effective encapsulation of drug inside the core and in outer cavities of beta-CD. The blank PCDAA@PCL-PEG-PCL NPs showed little cytotoxicity against HepG2 cells, but after loading PTX, they displayed significant cytotoxicity to the same cell line. Moreover, the surface engineering stratagem of many functional groups originating from PCDAA on the surface of PCL-PEG-PCL NPs, offers the ability to facilely conjugate fluorescent dyes or targeting ligands, which broad their application in biomedical field. This facile stratagem to modify polymeric nanoparticles can be extended to other particle systems. (C) 2014 Elsevier Ltd. All rights reserved.