Capacitive aptasensor based on interdigitated electrode for breast cancer detection in undiluted human serum

Author(s)

Arya, Sunil K. ^[1] ; Zhurauski, Pavel ^[1] ; Jolly, Pawan ^[1] ; Batistuti, Marina R. ^[2] ; Mulato, Marcelo ^[2] ; Estrela, Pedro ^[1]

Affiliation

^[1] Univ Bath, Dept Elect & Elect Engn, Bath BA2 7AY, Avon - England

^[2] Univ Sao Paulo, Dept Phys, BR-14040901 Ribeirao Preto, SP - Brazil

• Document type: Journal article
• Source: BIOSENSORS & BIOELECTRONICS; v. 102, p. 106-112, APR 15 2018.
• Web of Science Citations: 26

Abstract

We report the development of a simple and powerful capacitive aptasensor for the detection and estimation of human epidermal growth factor receptor 2 (HER2), a biomarker for breast cancer, in undiluted serum. The study involves the incorporation of interdigitated gold electrodes, which were used to prepare the electrochemical platform. A thiol terminated DNA aptamer with affinity for HER2 was used to prepare the bio-recognition layer via self-assembly on interdigitated gold surfaces. Non-specific binding was prevented by blocking free spaces on surface via starting block phosphate buffer saline-tween20 blocker. The sensor was characterized using cyclic voltammetry, electrochemical impedance spectroscopy (EIS), atomic force microscopy and contact angle studies. Non-Faradic EIS measurements were utilized to investigate the sensor performance via monitoring of the changes in capacitance. The aptasensor exhibited logarithmically detection of HER2 from 1 pM to 100 nM in both buffer and undiluted serum with limits of detection lower than 1 pM. The results pave the way to develop other aptamer-based biosensors for protein biomarkers detection in undiluted serum. (AU)

• FAPESP's process: 15/14403-5 - Detection of changes related to breast cancer using charge sensors or mass sensors coupled to DNA monolayers
• Grantee: Marina Ribeiro Batistuti Sawazaki
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate