A Highly Selective Electrochemical DNA-Based Sensor That Employs Steric Hindrance Effects to Detect Proteins Directly in Whole Blood.
Here we describe a highly selective DNA-based electrochemical sensor that utilizes steric hindrance effects to signal the presence of large macromolecules in a single-step procedure. We first show that a large macromolecule, such as a protein, when bound to a signaling DNA strand generates steric hindrance effects, which limits the ability of this DNA to hybridize to a surface-attached complementary strand. We demonstrate that the efficiency of hybridization of this signaling DNA is inversely correlated with the size of the molecule attached to it, following a semilogarithmic relationship. Using this steric hindrance hybridization assay in an electrochemical format (eSHHA), we demonstrate the multiplexed, quantitative, one-step detection of various macromolecules in the low nanomolar range, in <10 min directly in whole blood. We discuss the potential applications of this novel signaling mechanism in the field of point-of-care diagnostic sensors.
Laboratory of Biosensors & Nanomachines, Département de Chimie, Université de Montréal , Montréal, Québec H3T 1J4, Canada.
Sahar Sadat
SS
Mahshid
Laboratory of Biosensors & Nanomachines, Département de Chimie, Université de Montréal , Montréal, Québec H3T 1J4, Canada.
Sébastien
S
Camiré
Dipartimento di Scienze e Tecnologie Chimiche, University of Rome Tor Vergata , Rome 00133, Italy.
Francesco
F
Ricci
Laboratory of Biosensors & Nanomachines, Département de Chimie, Université de Montréal , Montréal, Québec H3T 1J4, Canada.
Alexis
A
Vallée-Bélisle
D001798:Blood Proteins / Q000032:analysis*; D004247:DNA / Q000737:chemistry*; D004563:Electrochemistry / Q000379:methods*
D001798:Blood Proteins; D004247:DNA