Sensitive
Immunosensor for N‑Terminal Pro-brain Natriuretic Peptide Based
on N‑(Aminobutyl)-N-(ethylisoluminol)-Functionalized Gold Nanodots/Multiwalled
Carbon Nanotube Electrochemiluminescence Nanointerface
- Publication date
- Publisher
Abstract
A novel
electrochemiluminescence (ECL) immunosensor was developed for the
determination of N-terminal pro-brain natriuretic peptide (NT-proBNP)
by using N-(aminobutyl)-N-(ethylisoluminol) (ABEI)-functionalized
gold nanodots/chitosan/multiwalled carbon nanotubes (ABEI/GNDs/chitosan/COOH-MWCNTs)
hybrid as nanointerface. First, ABEI/GNDs/chitosan/COOH-MWCNTs hybrid
nanomaterials were grafted onto the surface of ITO electrode via the
film-forming property of hybrid nanomaterials. The anti-NT-proBNP
antibody was connected to the surface of modified electrode by virtue
of amide reaction via glutaraldehyde. The obtained sensing platform
showed strong and stable ECL signal. When NT-proBNP was captured by
its antibody immobilized on the sensing platform via immunoreaction,
the ECL intensity decreased. Direct ECL signal changes were used for
the determination of NT-proBNP. The present ECL immunosensor demonstrated
a quite wide linear range of 0.01–100 pg/mL. The achieved low
detection limit of 3.86 fg/mL was about 3 orders of magnitude lower
than that obtained with electrochemistry method reported previously.
Because of the simple and fast analysis, high sensitivity and selectivity,
and stable and reliable response, the present immunosensor has been
successfully applied to quantify NT-proBNP in practical plasma samples.
The success of the sensor in this work also confirms that ABEI/GNDs/chitosan/COOH-MWCNTs
hybrid is an ideal nanointerface to fabricate a sensing platform.
Furthermore, the proposed strategy could be applied in the detection
of other clinically important biomarkers