High-Sensitive Electrochemiluminescence C-Peptide Biosensor via the Double Quenching of Dopamine to the Novel Ru(II)-Organic Complex with Dual Intramolecular Self-Catalysis

Abstract

Here, a novel Ru(II)-organic complex (Ru-PEI-ABEI) with high electrochemiluminescence (ECL) efficiency was proposed to construct a sensitive quenching-typed ECL biosensor for C-peptide (C-P) measurement based on the double quenching effect of dopamine (DA). The high ECL efficiency of Ru-PEI-ABEI was originated from the dual intramolecular self-catalysis including intramolecular coreaction between polyethylenimine (PEI) and Ru(bpy)(mcbpy), and intramolecular ECL resonance energy transfer (ECL-RET) from N-(aminobutyl)-N-(ethylisoluminol) (ABEI) to Ru(bpy)(mcbpy), which would generate a strong initial ECL signal. Through sandwiched immunoreaction and 3D DNA walking machine, a certain amount of target C-P was converted to a large amount of intermediate DNA that could further trigger hybridization chain reaction (HCR) to introduce into massive DA which not only could quench the ECL of Ru(bpy)(mcbpy), but also quench the ECL of ABEI. Thus, the double quenching effect of DA would effectively quench the ECL of Ru-PEI-ABEI, leading to an obviously decreased final ECL signal. Thus, a sensitive quenching-typed ECL biosensor was constructed for C-P detection with a linear range from 50 fg mL to 16 ng mL and an estimated detection limit of 16.7 fg mL. The dual intramolecular self-catalyzed strategy and the double quenching strategy based on one quencher to the same luminous reagent proposed in this work would provide new thought in both ECL signal enhancement and quenching efficiency improvement.

DNA Technology-assisted Signal Amplification Strategies in Electrochemiluminescence Bioanalysis

“…Further combining with a well-designed DNA probe, a ratiometric strategy was proposed for the sensitive and accurate evaluation of CD44 expression on MCF-7 cells [113]. Wang et al measured C-peptide by utilizing a NEase (Nb.BvCI)powered walking machine to produce intermediate ssDNA, which further initiated the HCR for DA loading, and the massive DA exhibited a dual quenching effect to the ECL of Ru-PEI-ABEI [114]. Ultrasensitive miR-21 detection was also realized by anchoring enormous Fc on the sensing surface via the target-initialed HCR self-assembly, and the Fc quenched the ECL of luminol/dissolved O 2 system with coreaction accelerators of ZnO nanostars and MnO x microflowers, respectively [115,116].…”

MALDI-TOF mass spectrometry-based quantification of C-peptide in diabetes patients

“…6,7 However, an increased sensitivity of the method is necessary, requiring both a reaction that stimulates compounds to increase the initial luminescence and an appropriate quenching reagent to decrease the final ECL signal. 8 Newly developed methods for effectively overcoming the obstacles facing C-peptide measurements have been described. More specifically, high-performance liquid chromatography (HPLC) and high-resolution LC-MS/MS have both been applied to detect and quantify C-peptide in clinical samples.…”

Rapid detection of staphylococcal enterotoxin B in milk samples based on fluorescence hybridization chain reaction amplification

“…To date, this signal amplication has been applied in various biosensor platforms, including color, 28,29 uorescence, 7,[30][31][32] chemiluminescence, [33][34][35] and electrochemical. 8,[36][37][38][39] Mostly traditional HCR-based aptasensor need to wash unbound probes and long incubation period.…”