A universal quantum dots-aptamer probe for efficient cancer detection and targeted imaging.

Targeted quantum dots have shown as an analytical and imaging tool for cancer detection and molecular imaging. Aptamers have recently been demonstrated as ideal candidates for molecular targeting applications. In the present work, quantum dots (QDs) were encapsulated with functional poly(ethylene glycol)-phospholipids to improve their solubility in water solution. The as-prepared QDs were then conjugated with the AS1411 aptamer recognizing the nucleolin overexpressed on cancer cell surface. The recognition of QD-Aptamer nanocomplex to breast cancer cells was demonstrated using confocal microscopy, and the viability of QDs-aptamer bioconjugate bound cells were not affected within 24 h, indicating that the probe was biocompatible and suitable for in vitro diagnostic assays and live cell imaging. Such well-defined aptamer-conjugated QDs nanoprobe was simple and universal to be extended to prepare various aptamer-nanoparticles hybrid systems for cancer targeting and molecular imaging applications.