Polyvinylpyrrolidone as a polymer template for Cu-In-S quantum dots: Effect on optical properties

Ternary I-III-VI quantum dots (QDs) are promising candidates for biomedical and bio-imagining applications. This is a result of the presence of less toxic elements compared to traditional QDs. Polymers are biocompatible, biodegradable, and nonimmunogenic, making them exceptionally suitable for in vivo therapeutic applications. Coating QDs with polymers has been reported to improve QDs stability, reduce toxicity, and introduce chemical functionalities on the surface of the QDs. Polyvinylpyrrolidone (PVP) is an amorphous water-soluble and non-toxic polymer commonly used in the pharmaceutical and biomedical industry as a vehicle for dispersing and suspending drugs. In this study, Cu-In-S QDs was synthesized hydrothermally using as dual stabilizers (i.e. glutathione and sodium citrate). The optical properties of the QDs proved to be composition and pH-dependent as an increase in intensity and tuneability of the emission peaks was obtained with varying synthesis parameters. To eliminate the shoulder peak due to the surface defect in the Cu-In-S QDs and improve the optical properties of the bare QDs, the Cu-In-S QDs was coated with PVP. For optimum synthesis conditions, pre-synthesis exposure of the QDs to varying amounts of the polymer was investigated. The generated (PVP) Cu-In-S QDs yielded different behaviour in terms of stability, optical properties (UV and PL), and surface coating compared to the core Cu-In-S QDs. The distinctive photophysical properties of the (PVP) Cu-In-S QDs paves the development of quality polymer coated Cu-In-S QDs for bio-imaging application.Copyright (c) 2021 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the International Conference on Applied Research and Engineering 2021

Automated summary

Ternary I-III-VI quantum dots (QDs) have the potential for biomedical and bio-imagining applications due to the presence of less toxic elements compared to traditional QDs. Coating QDs with polymers, such as polyvinylpyrrolidone (PVP), can improve their stability, reduce toxicity, and introduce chemical functionalities on their surface. In this study, Cu-In-S QDs were successfully synthesized and coated with PVP, resulting in improved optical properties and stability.