(B, N)-codoped carbon dots for sensitive luteolin detection and HepG2 cell imaging

Luteolin (3′,4′,5,7-tetrahydroxyflavone, LTL) is a kind of hydrophobic flavonoid, which has a number of pharmacological actions. It has a number of pharmacological actions, including anti-inflammatory, antioxidant, anticancer, and antihepatic fibrosis properties. High-dose LTL, on the other hand, can cause oxidative DNA damage and hydroxyl radical generation. It is critical to create easy, sensitive, and dependable LTL detection technologies and delivery methods for LTL quality control, clinical drug monitoring and enhancing drug bioavailability. In this work, a novel phenylboronic acid derived quantum dots (P-QDs) were synthesized for LTL sensitive detection and pH-responsive delivery. It showed remarkable selectivity and a brilliant fluorescence with a quantum yield of 43.62 %. In vitro experiments reveal negligible cytotoxicity. P-QDs and LTL coupling (P-QDs/LTL) showed powerful proliferation inhibition and migration restriction effects on HepG2 cells. In addition, P-QDs/LTL could time-dependently release it to restore fluorescence in the microacidic environment of HepG2 cells, thus demonstrating satisfactory fluorescence imaging capability. This strategy demonstrated a favourable linear relationship between LTL concentration and the fluorescence intensity of P-QDs in the range of 0.02–200 μM ( R 2  = 0.9952), with a detection limit of 1.16 nM (S/N=3). The recoveries in different real samples were in the range of 85.23 %-108.04 % with RSDs ≤6.1 %. The material is both a new attempt at LTL detection methodology and has significant promise for providing pH-responsive intracellular release of drug monitoring and cancer therapies from naked QDs without the requirement for sophisticated modified grafting.