TY - CHAP
T1 - Folding- and Dynamics-Based Electrochemical DNA Sensors
AU - Lai, Rebecca Y.
PY - 2017
Y1 - 2017
N2 - A number of electrochemical DNA sensors based on the target-induced change in the conformation and/or flexibility of surface-bound oligonucleotides have been developed in recent years. These sensors, which are often termed E-DNA sensors, are comprised of an oligonucleotide probe modified with a redox label (e.g., methylene blue) at one terminus and attached to a gold electrode via a thiol–gold bond at the other. Binding of the target to the DNA probe changes its structure and dynamics, which, in turn, influences the efficiency of electron transfer to the interrogating electrode. Since electrochemically active contaminants are less common, these sensors are resistant to false-positive signals arising from the nonspecific adsorption of contaminants and perform well even when employed directly in serum, whole blood, and other realistically complex sample matrices. Moreover, because all of the sensor components are chemisorbed to the electrode, the E-DNA sensors are essentially label-free and readily reusable. To date, these sensors have achieved state-of-the-art sensitivity, while offering the unprecedented selectivity, reusability, and the operational convenience of direct electrochemical detection. This chapter reviews the recent advances in the development of both “signal-off” and “signal-on” E-DNA sensors. Critical aspects that dictate the stability and performance of these sensors are also addressed so as to provide a realistic overview of this oligonucleotide detection platform.
AB - A number of electrochemical DNA sensors based on the target-induced change in the conformation and/or flexibility of surface-bound oligonucleotides have been developed in recent years. These sensors, which are often termed E-DNA sensors, are comprised of an oligonucleotide probe modified with a redox label (e.g., methylene blue) at one terminus and attached to a gold electrode via a thiol–gold bond at the other. Binding of the target to the DNA probe changes its structure and dynamics, which, in turn, influences the efficiency of electron transfer to the interrogating electrode. Since electrochemically active contaminants are less common, these sensors are resistant to false-positive signals arising from the nonspecific adsorption of contaminants and perform well even when employed directly in serum, whole blood, and other realistically complex sample matrices. Moreover, because all of the sensor components are chemisorbed to the electrode, the E-DNA sensors are essentially label-free and readily reusable. To date, these sensors have achieved state-of-the-art sensitivity, while offering the unprecedented selectivity, reusability, and the operational convenience of direct electrochemical detection. This chapter reviews the recent advances in the development of both “signal-off” and “signal-on” E-DNA sensors. Critical aspects that dictate the stability and performance of these sensors are also addressed so as to provide a realistic overview of this oligonucleotide detection platform.
KW - Alternating current voltammetry
KW - Blood serum
KW - Differential pulse voltammetry
KW - Electrochemical DNA sensors
KW - Methylene blue
KW - Nanoelectrode
KW - Screen-printed carbon electrode
KW - Self-assembled monolayer
KW - Sharpless “click” chemistry
KW - Single-base mismatch
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U2 - 10.1016/bs.mie.2017.02.001
DO - 10.1016/bs.mie.2017.02.001
M3 - Chapter
C2 - 28336065
AN - SCOPUS:85015643908
T3 - Methods in Enzymology
SP - 221
EP - 252
BT - Methods in Enzymology
PB - Academic Press Inc.
ER -