Nucleic acid electrochemical and electromechanical biosensors: a review of techniques and developments

Abstract

This review comprises the last decade’s development on experimental techniques for electrochemical and electromechanical sensing of nucleic acids, which originate from pathogenic bacteria, parasites, and viruses commonly found in food, water, and medical context. The electrochemical devices that are of primary interest are those that use voltammetry for detecting DNA and RNA-associated electrochemically active molecules at the working electrode. Attograms of nucleic acids have been reported to be detectable with electrochemical sensors in a batch-mode measurement arrangement. The mass-sensing electromechanical devices sense nucleic acids at the femtogram levels in a flow format without a molecular technique for amplifying target strand using polymerase chain reaction. Both underlying physics and methods of various studies are summarized, with discussion on limitations and potentials. We call attention to the need for sensors that not only detect but also confirm detection, as false negatives are not acceptable when one measures pathogenic species.

Keywords

• biosensor
• cantilever
• genosensor
• nucleic acid detection
• quartz crystal microbalance
• voltammetry