Preparation of yellow emissive nitrogen-doped carbon dots from o-phenylenediamine and their application in curcumin sensing

Abstract

In this work, o-phenylenediamine (o-PD) and ethanol are used as raw materials, and a simple solvothermal method is used to prepare yellow emissive nitrogen-doped CDs (YNCDs) (with yellow emission λ_ex/λ_em = 410/555 nm). Based on the inner filter effect (IFE), curcumin can effectively inhibit the photoluminescence of YNCDs. Using YNCDs as nanoprobes, a “turn-off” sensor platform for detecting curcumin is established, with a lower detection limit (3S/N) of 0.01 μmol L⁻¹. More importantly, the developed sensor platform achieves highly selective and sensitive detection of curcumin in real samples including curry powder, human urine, human serum and river water, with satisfactory accuracy and recovery. Furthermore, the excellent optical properties of YNCDs can also be used in invisible inks in the fields of patterning, information storage and anti-counterfeiting.