• quantum dots;
  • cellular imaging;
  • nanoparticles;
  • nonspecific cellular binding;
  • cancer nanotechnology

Quantum dots (QDs) as luminescence probes play an important role in the field of life sciences and medicine in recent decades. However, hydrophobic QDs have many limitations in applications for biological imaging such as insolubility in aqueous solutions and nonspecific binding to cellular membranes and so on. This article describes the design and synthesis of d-α-tocopheryl polyethylene glycol 3350 succinate (TPGS3350)-conjugated QDs (TPGS3350-QDs) nanoparticles (NPs) for effective reduction of nonspecific cellular binding of QDs for biological imaging. TPGS3350 with n-poly(ethylene glycol) (PEG)3350 group was used in order to enhance the stabilization and water solubility of QDs, and reduce nonspecific cellular binding of NPs with the function of long-chain PEG3350. We have demonstrated that TPGS3350-QDs NPs show good stability and dispersion in aqueous solutions and that small amount of TPGS3350-QDs NPs were nonspecific bound with Michigan Cancer Foundation-7 (MCF-7) cells in comparison of mercaptoacetic acid-coated QDs NPs, which confirmed TPGS3350 can efficiently reduce nonspecific cellular binding due to the effect of PEG3350 in TPGS3350. The nonspecific binding of TPGS3350-QDs NPs was also found to be much lower than that of TPGS-QDs NPs. The developed TPGS3350-QDs NPs in this study could be a promising tool for molecular imaging such as in vivo cell trafficking studies. © 2014 American Institute of Chemical Engineers AIChE J, 60: 1591–1597, 2014