Highly Efficient PTCA/Co₃O₄/CuO/S₂O₈^2– Ternary Electrochemiluminescence System Combined with a Portable Chip for Bioanalysis

Abstract

Herein, we reported an efficient electrochemiluminescence (ECL) biosensor chip for sensitive detection of neuron-specific enolase (NSE). First, 3,4,9,10-perylenetetracarboxylic acid with good luminescence characteristics was used as a luminophore to obtain a stable ECL signal. Subsequently, hollow porous Co3O4/CuO concave polyhedron nanocages (CPNCs) were designed as co-reaction promoters to amplify the luminescence signals for highly sensitive trace detection of NSE. In brief, the rapid cyclic conversion of Co3+/Co2+ and Cu2+/Cu+ redox pairs could continuously catalyze the reduction of persulfate (S2O8 2–), thus providing a large number of essential active intermediates (SO4 •–) for ECL emission. Meanwhile, the unique structure of Co3O4/CuO CPNCs possessed a large specific surface area, which greatly improved its catalytic efficiency. Third, NKFRGKYKC was developed as an affinity ligand for specific antibody fixation, which improved incubation efficiency and protected bioactivity of antibodies. Finally, we independently designed a microchip and applied it for ECL detection to improve the practical application ability of the sensor. The developed biosensor exhibited good sensitivity with a wide linear range (10 fg/mL to 100 ng/mL) and a low detection limit (3.42 fg/mL), which played an active role in the clinical application of sensing analysis.

Synergistic Multieffect Catalytic Amplified Cathodic Electrochemiluminescence Biosensor via Target Binding-Induced Aptamer Conformational Changes for the Ultrasensitive Detection of Synthetic Cathinone

“…Herein, the 5,5-dimethyl-1pyrroline N-oxide (DMPO) free-radical trapping agent was used to analyze the EPR spectrum of the Ag@CuCo 2 O 4 / PTCA-COF/S 2 O 8 2− system. 44,45 As observed in Figure 2D, it was a typical quadruple peak with a peak intensity ratio of 1:2:2:1, which corresponded to the DMPO−OH adducts and confirmed the production of hydroxyl radicals (OH • ). Meanwhile, between the four above-mentioned typical peaks, there were two additional smaller peaks that were indicative of DMPO−SO 4 adducts and showed the existence of SO 4…”

Highly Efficient Dual-Color Luminophores for Sensitive and Selective Detection of Diclazepam Based on MOF/COF Bi-Mesoporous Composites

“…Furthermore, the ESR spectrum of the Cu 3 (HHTP) 2 /PTCA-COF/S 2 O 8 2– system was tested by using 5,5-dimethyl-1-pyrroline N -oxide (DMPO) as a free radical trapping agent (as shown in Figure C). First, no signals were observed in the Cu 3 (HHTP) 2 and DMPO (curve a) solution whereas a unique hyperfine cleavage of the DMPO-OH adduct (1:2:2:1 quartet pattern) and DMPO-SO 4 adduct appeared in the mixture of K 2 S 2 O 8 and DMPO (curve b), implying the generation of SO 4 ·– (radical ion) and OH (hydroxyl radical). − Interestingly, when Cu 3 (HHTP) 2 was added to the S 2 O 8 2– and DMPO solution, the DMPO-SO 4 and DMPO-OH signals were significantly enhanced (curve c), which indicated that Cu 3 (HHTP) 2 could efficiently interact with S 2 O 8 2– as co-reaction accelerators to produce massive amounts of OH and SO 4 ·– . Therefore, we concluded that the enhancement of composite ECL was mainly due to the dual enhancement effect of Cu 3 (HHTP) 2 on the PTCA-COF.…”

Electrochemiluminescence resonance energy transfer between a Ru-ZnMOF self-enhanced luminophore and a double quencher ZnONF@PDA to detect NSE

“…1 NSE is overexpressed in the sera of small cell lung cancer patients (serum concentration >15 ng mL −1 ), 2,3 and is also used for the early diagnosis and prognosis of small cell lung cancer. 4 Many methods have been developed to detect NSE, such as electrochemical sensing, 5 fluorescence immunoassay, 6 photochemistry, 7 resonance light scattering, 8 and electrochemiluminescence. 9 Electrochemiluminescence (ECL) involves photo-excited state energy relaxation and an electrochemical reaction after photon emission during irradiation.…”