Carbon within carbon: growth of excitation-independent CDs within functional mesoporous carbon towards detection and adsorption of a specific nitrofuran class of antibiotics

Abstract

The rampant use of antibiotics has led to significant environmental pollution and the emergence of antibiotic resistance, necessitating effective detection and remediation methods. To address these pressing concerns, an innovative functional material has been developed, comprising a mesoporous matrix and a luminescent tag, both composed of carbon for the detection and removal of specific antibiotics from aqueous solutions. Initially, a high surface area bearing mesoporous carbon material with regular spherical geometry and ordered pores (5.4 nm) was synthesized and amine-functionalized with (3-aminopropyl)triethoxysilane to form OMC@NH₂. Subsequently, a hydrothermal process was employed to load carbon dots (CDs) in situ within the amine-functionalized mesoporous carbon material (CD@OMC@NH₂) using carbon dot precursors. The resulting blue-green luminescent material exhibited excitation-independent luminescence and demonstrated the ability to selectively detect the antibiotics nitrofurantoin (NFT) and furazolidone (FZD) through a combined effect of the IFE (inner filter effect) and FRET-based quenching mechanism. The material's detection performance was assessed by calculating the LOD (Limit of Detection), LOQ (Limit of Quantification), and L-R (Linear Range) values, which indicated its superior and sensitive detection capabilities. Moreover, the material exhibited exceptional detection parameters, a high adsorption capacity, and easy recyclability for specific antibiotics, making it a sustainable option for environmental sample monitoring.