Mesoporous silica-encapsulated nitrogen-doped fluorescent carbon dots modified polydopamine composites for monitoring non-steroidal anti-inflammatory drugs

A one-pot hydrothermal process incorporated nitrogen-doped fluorescent carbon dots (N-FCDs) into the pores of mesoporous silica (m-SiO2). Under weakly alkaline conditions, the m-SiO2/N-FCDs were further functionalized with dopamine to develop m-SiO2/N-FCDs modified polydopamine (m-SiO2/N-FCDs/PDA). The m-SiO2/N-FCDs/PDA exhibited emission at a wavelength of 520 nm (λexc. = 440 nm) and demonstrated excellent quenching efficiency in the presence of NSAIDs (aspirin, diclofenac, ketoprofen, naproxen, and ibuprofen) with a detection limit of 0.045 – 1.43 nM. Furthermore, the m-SiO2/N-FCDs/PDA was utilized to detect NSAIDs in tap and river water and pharmaceutical commercial tablets showing high recoveries of 90.96–100.41 % with RSD < 4.