An antifouling electrochemiluminescence sensor based on mesoporous CuO2@SiO2/luminol nanocomposite and co-reactant of ionic liquid functionalized boron nitride quantum dots for ultrasensitive NSE detection
A novel electrochemiluminescence (ECL) sensing platform was developed for the detection of neuron-specific enolase (NSE), based on the nanocomposite of mesoporous silica encapsulated CuO2 nanoparticles and electrostatically attracted luminol. An antifouling membrane of polyvinylidene fluoride modified by polyethyleneimine and dopamine was introduced to improve the immobilization of nanocomposite and the stability of ECL signal; Au nanoparticles were loaded on the membrane surface for binding the antibody. The CuO2 nanoparticles were capable of supplying H2O2, while the amino ionic liquid functionalized boron nitride quantum dots as co-reactant of luminol could effectively enhance the ECL signal. The resulting ECL immunosensing platform thus showed excellent performance. Over the concentration range of 5-500 ng/mL, it presented a good linear response; the detection limit was down to 24.5 pg/mL. In addition, it had high selectivity and stability. The sensor has been successfully applied to determine target NSE in human serum samples. This work provides some insights into the further design of high-performance ECL sensors.