Ultra-high sensitivity of the non-immunological affinity of graphene oxide-peptide-based surface plasmon resonance biosensors to detect human chorionic gonadotropin

Nan-Fu Chiu; Chia-Tzu Kuo; Ting-Li Lin; Chia-Chen Chang; Chen-Yu Chen

doi:10.1016/j.bios.2017.03.008

Ultra-high sensitivity of the non-immunological affinity of graphene oxide-peptide-based surface plasmon resonance biosensors to detect human chorionic gonadotropin

Biosens Bioelectron. 2017 Aug 15:94:351-357. doi: 10.1016/j.bios.2017.03.008. Epub 2017 Mar 7.

Authors

Nan-Fu Chiu¹, Chia-Tzu Kuo², Ting-Li Lin², Chia-Chen Chang³, Chen-Yu Chen⁴

Affiliations

¹ Institute of Electro-Optical Science and Technology, National Taiwan Normal University, No. 88, Section 4, Ting-Chou Road, Taipei 11677, Taiwan. Electronic address: nfchiu@ntnu.edu.tw.
² Institute of Electro-Optical Science and Technology, National Taiwan Normal University, No. 88, Section 4, Ting-Chou Road, Taipei 11677, Taiwan.
³ Institute of Biomedical Engineering, National Taiwan University, Taipei 10617, Taiwan.
⁴ Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei 10449, Taiwan; Department of Medicine, Mackay Medical College, Taipei 252, Taiwan. Electronic address: f122481@mmh.org.tw.

PMID: 28319902
DOI: 10.1016/j.bios.2017.03.008

Abstract

Specific peptide aptamers can be used in place of expensive antibody proteins, and they are gaining increasing importance as sensing probes due to their potential in the development of non-immunological assays with high sensitivity, affinity and specificity for human chorionic gonadotropin (hCG) protein. We combined graphene oxide (GO) sheets with a specific peptide aptamer to create a novel, simple and label-free tool to detect abnormalities at an early stage of pregnancy, a GO-peptide-based surface plasmon resonance (SPR) biosensor. This is the first binding interface experiment to successfully demonstrate binding specificity in kinetic analysis biomechanics in peptide aptamers and GO sheets. In addition to the improved affinity offered by the high compatibility with the target hCG protein, the major advantage of GO-peptide-based SPR sensors was their reduced nonspecific adsorption and enhanced sensitivity. The calculation of total electric field intensity (ΔE) in the GO-based sensing interfaces was significantly enhanced by up to 1.2 times that of a conventional SPR chip. The GO-peptide-based chip (1mM) had a high affinity (K_A) of 6.37×10¹²M^-1, limit of detection of 0.065nM and ultra-high sensitivity of 16 times that of a conventional SPR chip. The sensitivity of the slope ratio of the low concentration hCG protein assay in linear regression analysis was GO-peptide (1mM): GO-peptide (0.1mM): conventional chip (8-mercaptooctanoic acid)-peptide (0.1mM)=8.6: 3.3: 1. In summary, the excellent binding affinity, low detection limit, high sensitivity, good stability and specificity suggest the potential of this GO-peptide-based SPR chip detection method in clinical application. The development of real-time whole blood analytic and diagnostic tools to detect abnormalities at an early stage of pregnancy is a promising technique for future clinical application.

Keywords: Graphene oxide (GO); Human chorionic gonadotropin (hCG); Peptide aptamer; Surface plasmon resonance (SPR).

MeSH terms

Biosensing Techniques / methods*
Chorionic Gonadotropin / isolation & purification*
Gold / chemistry
Graphite / chemistry
Humans
Kinetics
Limit of Detection
Peptides / chemistry*
Surface Plasmon Resonance

Substances

Chorionic Gonadotropin
Peptides
Gold
Graphite