Sensitive electrogenerated chemiluminescence peptide-based biosensor for the determination of troponin I with gold nanoparticles amplification

Abstract

A sensitive electrogenerated chemiluminescence (ECL) peptide-based biosensor was fabricated for the determination of troponin I (TnI) by employing gold nanoparticles as amplification platform. Two specific peptides including peptide1 with a sequence of CFYSHSFHENWPS and peptide2 with a sequence of FYSHSFHENWPSK were employed as capture peptide and report peptide, respectively. The peptide2 was labeled with ruthenium bis(2,2′-bipyridine) (2,2′-bipyridine-4,4′-dicarboxylic acid)-N-hydroxysuccinimide ester (Ru(bpy) 2 (dcbpy)NHS) at NH 2 -containing lysine via acylation reaction and utilized as the ECL probe. Gold nanoparticles were electrodeposited onto gold electrode and used as an amplification platform. The peptide-based biosensor was fabricated by self-assembling peptide1 onto the surface of gold nanoparticles-modified gold electrode through a thiolcontaining cysteine at the end of the peptide1. When the biosensor reacted with target TnI, and then incubated with the ECL probe, a strong ECL response was electrochemically generated. The ECL intensity is directly proportional to the logarithm of the concentration of TnI in the range from 1 to 300 pg/mL. The biosensor employing gold nanoparticles as amplification platform shows high sensitivity for the detection of TnI with a detection limit of 0.4 pg/mL (S/N =3). Moreover, the biosensor is successfully applied to analysis of TnI in human serum sample. This work demonstrates that the combination of a highly binding peptide with nanoparticle amplification is a great promising approach for the design of ECL biosensor.

Sensitive and versatile electrogenerated chemiluminescence biosensing platform for protein kinase based on Ru(bpy)32+ functionalized gold nanoparticles mediated signal transduction

“…The ECL biosensor was fabricated by self-assembly peptide on gold electrode via thiol-gold bond between cysteine residue in peptide and gold electrode as our previous work [31]. Prior to the experiment, a gold electrode was polished with 0.3 µm, 0.05 µm and 0.01 µm alumina slurry and then ultra-sonicated in water for 5 min, and then cleaned electrochemically by a linear scanning potential between 0 and +1.5 V in 0.10 M H 2 SO 4 until a stable cyclic voltammogram was obtained [32].…”

Electrogenerated chemiluminescence peptide-based biosensing method for cardiac troponin I using peptide-integrating Ru(bpy)3 2+-functionalized gold nanoparticles as nanoprobe

“…ECL and electrochemical setups were similar to those in our previous work [27]. The integrated ECL imaging system included a CHI 660 electrochemical workstation (Shanghai Chenhua Instrument Co. Ltd., China) suitable for the needed potential for the ECL-triggered reaction, an Olympus IX-51 inverted microscope (Olympus corporation, Tokyo, Japan) and a Magnafire model iXon + DU-897 Andor EMCCD (Andor Technology Ltd., Belfast, Northern Ireland).…”

“…Generally, AuNPs are employed in the modification of electrodes [26,27] as they provide a large surface area and facilitate the electron transfer between active molecules and electrodes. Moreover, AuNPs have been employed as carriers for conventional signals such as luminol [11,28] and ruthenium complexes [29] thus affording ECL signal amplification.…”

Heparin Gold Nanoparticles as a Colorimetric Probe for Cardiac Troponin I Detection

“…Recent studies indicate that cTnI concentrations in the range of 0.5-2 ng/mL are regarded as the borderline between normal people and patients [5]. After the outbreak of AMI, cTnI concentrations can go up to 550 ng/mL and remain elevated for a few days, while the other biomarker will decline rapidly [6,7].…”