Electrochemiluminescence resonance energy transfer for both “turn-off” detection of 2,4,6-trinitrophenol and “turn-on” detection of lidocaine hydrochloride using luminol-doped silica nanoparticles

Abstract It is the first time to develop electrochemiluminescence resonance energy transfer (ECRET) strategy using luminol-doped silica nanoparticles (luminol-SiNPs) for both “turn-off” detection of 2,4,6-trinitrophenol (TNP) and “turn-on” detection of anesthetic drug lidocaine hydrochloride (LDC). The spectral overlap of ECL emission of luminol-SiNPs with the absorption of TNP triggers ECRET from luminol-SiNPs to TNP and results in the decreased ECL signals. Besides, the specific interaction between TNP and LDC consumes TNP, accordingly prevents ECRET from luminol-SiNPs to TNP and achieves increasing ECL signals. The proposed ECRET strategy using luminol-SiNPs exhibits fast response (within 10 min), high sensitivity with LOD of 22.4 nM for TNP and 92.5 nM for LDC, respectively. It is also successfully applied in ECRET detection of TNP in lake water, LDC in human serum and commercial drug sample detections with satisfactory recoveries. More importantly, ECL of luminol-SiNPs is measured via linear sweep voltammetry by electrochemical reduction of dissolved oxygen at negative potential (– 1 V) and in no need of adding hydrogen peroxide (H 2 O 2 ). Reactive oxygen species be generated in situ and make luminol-SiNPs system emit ECL, which makes ECL of the whole luminol-SiNPs system more stable than luminol-H 2 O 2 system.