The Photoluminescence and Biocompatibility of CuInS2-Based Ternary Quantum Dots and Their Biological Applications

Abstract

Semiconductor quantum dots (QDs) have become a unique class of materials with great potential for applications in biomedical and optoelectronic devices. However, conventional QDs contains toxic heavy metals such as Pb, Cd and Hg. Hence, it is imperative to find an alternative material with similar optical properties and low cytotoxicity. Among these materials, CuInS2 (CIS) QDs have attracted a lot of interest due to their direct band gap in the infrared region, large optical absorption coefficient and low toxic composition. These factors make them a good material for biomedical application. This review starts with the origin and photophysical characteristics of CIS QDs. This is followed by various synthetic strategies, including synthesis in organic and aqueous solvents, and the tuning of their optical properties. Lastly, their significance in various biological applications is presented with their prospects in clinical applications.

Cu-Enhanced Efficient Förster Resonance Energy Transfer in PBSA Sunscreen-Associated Ternary CuxCd1–xS Quantum Dots

“…In this way, the composition-dependent band gap can be tuned with the increase in Cu content since VB is pushed toward a higher energy, and thereby, the band gap is decreased. 19,37,38 In CCS QDs, as the Cu content increases from 2 to 10 mM, the band gap decreases from 3.09 to 2.91 eV, as shown in Figure 1c.…”

“…Moreover, in ternary copper chalcogenides, VB is composed of 3d orbitals of Cu that are hybridized with the p-orbitals of the chalcogen element, while CB is composed of 4s-orbitals of Cu with some p-character mixing from the chalcogen element. In this way, the composition-dependent band gap can be tuned with the increase in Cu content since VB is pushed toward a higher energy, and thereby, the band gap is decreased. ,, In CCS QDs, as the Cu content increases from 2 to 10 mM, the band gap decreases from 3.09 to 2.91 eV, as shown in Figure c.…”

Green Synthesis of Carboxymethyl Chitosan-Based CuInS2 QDs with Luminescent Response toward Pb2+ Ion and Its Application in Bioimaging

“…Figure c shows the fluorescence spectra and change trends of different metal ions after adding CMC-CuInS 2 QD aqueous solution (the ion concentrations are all 1.0 × 10 –4 M). As shown in Figure d, the addition of Pb 2+ shows the most obvious fluorescence quenching effect on the CMC-CuInS 2 QDs aqueous solution, while other ions, such as Co 2+ , K + , Na + , and Mn 2+ , exhibit the very weak changes. , Besides, the ion anti-interference experiment was conducted to discuss the effects of Hg 2+ and Fe 3+ . As shown in Figure S3, after mixing 1.0 × 10 –4 M Hg 2+ and Fe 3+ with Pb 2+ , the fluorescence quenching effects are 0.36, 0.34, and 0.33, respectively.…”

Enhancing the FRET by tuning the bandgap of acceptor ternary ZnCdS quantum dots

“…The commonly used biocompatible ternary QDs involve AgInS, CuInS, and AgCuS. 23,24 Among the ternary QDs, ZnCdS QDs have earned too much attention in recent decades due to the incredible dependency of bandgap (2.4-3.7 eV) on their size and composition. 25,26 The novel properties of ZnCdS QDs lie in between ZnS and CdS QDs.…”