One-Pot Synthesis of Luminescent and Photothermal Carbon Boron-Nitride Quantum Dots Exhibiting Cell Damage Protective Effects.

Zero-dimensional boron nitride quantum dots (BNQDs) are arousing interest for their versatile optical, chemical, and biochemical properties. Introducing carbon contents in BNQDs nanostructures is a great challenge to modulate their physic-chemical properties and applications. Among the carbon moieties, phenolic groups have attracted attention for their biochemical properties and phenol-containing nanomaterials are showing great promise for biomedical applications. Herein, the first example of direct synthesis of water dispersible BNQDs exposing phenolic and carboxylic groups is presented. The carbon-BNQDs were prepared in a single step by solvent-assisted reaction of urea with boronic reagents and were characterized by optical absorption and luminescence techniques, Raman, FTIR and NMR spectroscopy, XPS, DLS, and AFM microscopy. The carbon-BNQDs exhibited nano-dimension, high photothermal conversion efficiency, pH-responsive luminescence and Z-potential, and good stability. The potential of the carbon-BNQDs to provide photothermal materials also in solid state by embedding in agarose substrate was successfully investigated. The carbon-BNQDs exhibited biocompatibility on colorectal adenocarcinoma cells (Caco-2) and protective effects from chemical and oxidative stress on Caco-2, osteosarcoma (MG-63) and microglial (HMC-3) cells. Amplicon mRNA-seq analyses for the expression of 56 genes involved in oxidative stress and inflammation were performed to evaluate the molecular events responsible for the cell protective effects of the carbon-BNQDs. This article is protected by copyright. All rights reserved.