Novel and simple electrochemical biosensor monitoring attomolar levels of miRNA-155 in breast cancer

Abstract

This work, describes for the first time, a simple biosensing design to yield an ultrasensitive electrochemical biosensor for a cancer biomarker detection, miRNA-155, with linear response down to the attomolar range. MiRNA-155 was selected for being overexpressed in breast cancer. The biosensor was assembled in two stages: (1) the immobilization of the anti-miRNA-155 that was thiol modified on an Au-screen printed electrode (Au-SPE), followed by (2) blocking the areas of non-specific binding with mercaptosuccinic acid. Atomic force microscopy (AFM) and electrochemical techniques including cyclic voltammetry (CV), impedance spectroscopy (EIS) and square wave voltammetry (SWV) confirmed the surface modification of these devices and their ability to hybridize successfully and stably with miRNA-155. The final biosensor provided a sensitive detection of miRNA-155 from 10 aM to 1.0 nM with a low detection limit (LOD) of 5.7 aM in real human serum samples. Good results were obtained in terms of selectivity towards breast cancer antigen CA-15.3 and bovine serum albumin (BSA). Raw fluid extracts from cell-lines of melanoma did not affect the biosensor response (no significant change of the blank), while raw extracts from breast cancer yielded a positive signal against miRNA-155. This simple and sensitive strategy is a promising alternative for simultaneous quantitative analysis of multiple miRNA in physiological fluids for biomedical research and point-of-care (POC) diagnosis.

Why the Gold Standard Approach by Mammography Demands Extension by Multiomics? Application of Liquid Biopsy miRNA Profiles to Breast Cancer Disease Management

“…Thus, the international oncology community is in active pursuit of non-invasive methods for the diagnosis and monitoring of BC patients, which could be introduced in clinical practice. Nowadays efforts are focusing on monitoring specific bodily fluid biomarkers for early and minimally invasive detection [88]. The background for this is the natural behavior of the malign disease, leading to its spread.…”

Silver Chloride/Ferricyanide-Based Quasi-Reference Electrode for Potentiometric Sensing Applications

“…[Fe(CN) 6 ] 3-/4serves as a mediator system in assessing AOA/OA of solid-phase objects in contact hybrid potentiometric method (CHPM) [8][9][10][11]; • [Fe(CN) 6 ] 3-/4is used as a redox probe to study processes in cyclic voltammetry [12][13][14][15][16] and electrochemical impedance spectroscopy [15][16][17]; • [Fe(CN) 6 ] 3-/4is used in bio- [18,19], immuno- [20] and aptasensors [21].…”

Ultrasensitive optical biosensor for detection of miRNA-155 using positively charged Au nanoparticles

“…Ultrasound, on the other hand, is a non-invasive and safe method, but it cannot be replaced with mammography. Thus, it is thoughtful to develop a non-invasive, simple and low-risk method for screening or diagnosing breast cancer 4 . Among the various cancer biomarkers, microRNAs (miRs) have recently attracted researchers’ attention.…”