Laser-synthesized fluorescent carbon quantum dots (CQDs) in liquids: harnessing their potential for biomedical applications

Carbon quantum dots (CQDs) have attracted significant interest for biological, catalytic, and energy applications due to their tunable fluorescence and unique physicochemical properties. Laser-based synthesis in liquids, particularly pulsed laser fragmentation in liquids (PLFL), offers an eco-friendly, scalable, and high-purity method for CQD production, though their practical biomedical applications remain underexplored. This work investigates PLFL-synthesized CQDs and demonstrates their functionality in sensing and drug delivery. CQDs were functionalized with aminophenylboronic acid to create a fluorescence-based, non-enzymatic glucose sensor exhibiting high photostability, a quantum yield of 35%, good selectivity, and a detection limit of 165 μM, with successful performance in saliva samples. Additionally, CQDs were incorporated into biocompatible polymeric nanoparticles for sorafenib delivery, enabling fluorescence tracking, enhanced anticancer efficacy, and strong anti-angiogenic effects in vitro and in vivo. Overall, PLFL-synthesized CQDs show strong promise as multifunctional platforms for biomedical sensing and drug delivery.