Quantum dots incorporated hydrogels for biomedical applications: a review

Quantum dot–hydrogel composites are advanced polymeric nanomaterials that have received significant recognition for their excellent biodegradability, making them highly suitable for diverse biomedical applications. In drug delivery applications, QD-hydrogel systems facilitate controlled and targeted therapeutic release while enabling real-time imaging and monitoring due to the intrinsic fluorescence of QDs. In tissue engineering, these composites provide a biocompatible scaffold with integrated imaging capabilities, allowing researchers to track cellular behavior and scaffold integration in vivo. Furthermore, in biosensing, QD-hydrogel platforms are used for the sensitive detection of biomolecules, as their fluorescence can be modulated by specific biological interactions. This review reports the recent advancements in QD-hydrogel composites, emphasizing synthesis methodologies such as hydrogel gelation in QD solutions, the blending of QDs into hydrogels post-gelation, the in-situ formation of QDs along with preformed hydrogels, and conjugation through QDs to fabricate hydrogels. This review specifically addresses biomedical applications, which include bioimaging, biosensing, and drug delivery, preceding an examination of the intrinsic issues related to design optimization, biocompatibility, along with bimodal applications, as well as future development prospects. This review will inform the advancement of QD-hydrogel fabrications and provide essential insights to motivate further research.