Formation of luminescent nanocomposite assemblies via electrostatic interaction

A novel luminescent nanocomposite assembly was prepared in aqueous solutions, via the electrostatic interaction between poly(ethylene glycol)-b  -poly(N,NN,N-dimethylaminoethyl methacrylate) (PEG-b-PDMAEMA) double hydrophilic block copolymer (DHBC) and thioglycolic acid (TGA)-stabilized CdTe quantum dots (QDs). By tuning the molar ratios of QDs to DHBC, the nanocomposite assemblies could be well controlled and the dimension of these regular spherical QDs/PEG-b-PDMAEMA assemblies ranged from 40 to 75 nm in aqueous media. As the periphery of QDs/PEG-b-PDMAEMA nanocomposite assembly was composed of PEG segments when the PDMAEMA blocks and QDs were immobilized inside the assembly, the cytotoxicity of the assembly was significantly reduced, compared with that of pure PEG-b-PDMAEMA and QDs. The nanocomposite assembly also exhibited superior stability in salt solutions and remained strongly photoluminescent even when free radicals existed. Thus, the QDs/PEG-b-PDMAEMA nanocomposite assembly is potentially useful for a number of applications in biolabeling and imaging.

Graphical abstractA novel luminescent nanocomposite assembly was prepared in aqueous solutions via the electrostatic interaction of PEG-b-PDMAEMA and QDs. The cytotoxicity of the nanocomposite assemblies was significantly reduced while the PDMAEMA blocks and QDs were immobilized inside the assembly.Figure optionsDownload full-size imageDownload as PowerPoint slide