New Generation Cadmium-Free Quantum Dots for Biophotonics and Nanomedicine

Abstract

This review summarizes recent progress in the design and applications of cadmium-free quantum dots (Cd-free QDs), with an emphasis on their role in biophotonics and nanomedicine. We first present the features of Cd-free QDs and describe the physics and emergent optical properties of various types of Cd-free QDs whose applications are discussed in subsequent sections. Selected specific QD systems are introduced, followed by the preparation of these Cd-free QDs in a form useful for biological applications, including recent advances in achieving high photoluminescence quantum yield (PL QY) and tunability of emission color. Next, we summarize biophotonic applications of Cd-free QDs in optical imaging, photoacoustic imaging, sensing, optical tracking, and photothermal therapy. Research advances in the use of Cd-free QDs for nanomedicine applications are discussed, including drug/gene delivery, protein/peptide delivery, image-guided surgery, diagnostics, and medical devices. The review then considers the pharmacokinetics and biodistribution of Cd-free QDs and summarizes current studies on the in vitro and in vivo toxicity of Cd-free QDs. Finally, we provide perspectives on the overall current status, challenges, and future directions in this field.

Flexible quantum dot light-emitting diodes for next-generation displays

“…[56][57][58][59][60][61][62] This issue become more significant in flexible/wearable displays, where the device is in direct contact with the human body. For instance, the European Union's Restriction of Hazardous Substances Directive regulates the use of Cd-based compounds in consumer electronics.…”

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Dipole Emission to Surface Plasmon-Coupled Enhanced Transmission in Diamond Substrates with Nitrogen Vacancy Center- Near the Surface

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