Assessing Near-Infrared Quantum Dots for Deep Tissue, Organ, and Animal Imaging Applications

Semiconductor quantum dots (Qdots) have emerged as novel ultrasensitive optical probes to target, detect, and image fundamental events occurring within the biological system. In particular, near-infrared (near-IR) Qdots holds great promise as in vivo contrast agents for real-time bioimaging capabilities. In this study, biocompatible near-IR Qdots are used to image organs, tissues, and cells. Compared to visible Qdots, we obtained a significant enhancement in signal detection sensitivity for imaging deep tissues and organs. In addition, biomolecules were used to target these optical contrast agents for multiplexed imaging of cells and organs in vivo. The ability to simultaneously distinguish emission profiles of multiple near-IR Qdots will likely emerge as important tools for addressing fundamental questions in molecular biology and in medical sciences.