Nucleic acid biosensors

J. Wang, Electrochemical nucleic acid biosensors. Anal. Chim. Acta 469, 63—71 (2002). 

Nucleic acid biosensors based on optical modes of detection represent another common approach for generating analytical signals based on nucleic acid hybridization. The methods discussed herein are based on methods that are suitable for the study of materials on surfaces. There are a number of different optical methods that have been described, with the most common being attenuated total reflectance (ATR), total internal reflection fluorescence (TIRF) and surface plasmon resonance (SPR) [15]. All of these methods work... 

Optical nucleic acid biosensors and microarrays based on fluorescence detection make use of fluorescent dyes to provide a measurable signal for target/probe hybridization. Ideally, fluorophores used for detecting nucleic acid hybridization should exhibit large molar absorptivity, resistance to pho-tobleaching, quantum yields that approach unity and the abibty to produce a resolvable signal at low concentrations both quickly and reproducibly [40]. 

Wang, J., 2002. Electrochemical nucleic acid biosensors. Anal. Chim. Acta, 469, pp. 63-71. Wang, J., Cai, X.H., Rivas, G., Shiraishi, H., Farias, P.A.M., and Dontha, N., 1996. DNA electrochemical biosensor for the detection of short DNA sequences related to the human immunodeficiency virus. Anal. Chem., 68, pp. 2629-2634. 

Analytical Applications of QCM-based Nucleic Acid Biosensors... 

Nucleic Acid-Based Biosensors. Nucleic acid biosensors have been created most commonly based upon detecting the extent of hybridization of an... 

Electrochemical Nucleic Acid Biosensors Based on Hybridization Detection for Clinical Analysis... 

Recently, some reports have indicated that electrochemical techniques in nucleic acid biosensors are well suited for measuring hybridization event [10]. 

Nucleic acid is a biosensor which integrates nucleic acid hybridization recognition with a signal transducer. Figure 13.1 is a schematic representation of a nucleic acid biosensor. 

Nucleic acid biosensors can be classified on the basis of their transduction technology. The transducer converts the nucleic acid hybridization recognition into a measurable anal3ttical signal [27-28]. Electrochemical, optical, piezoelectrical, acoustical, and mechanical transducers are among the many types found in DNA biosensors. 

Electrochemical nucleic acid biosensors are based on electrochemical transduction of the hybridization event and show great promise for detection of specific gene sequences related to inherited and infectious diseases. Electrochemical detection of specific DNA sequences has an advantage in reducing the size of the total detection system [36], The advantages of electrochemical nucleic acid biosensors include potential of miniaturization, short response time, ease of use, low cost, and compatibility with microfabrication techniques [37],... 

Early studies on electrochemical nucleic acid biosensors were based on electrochemical transduction of redox labels (indicators) that have significant different behaviors between dsDNA and ssDNA. These intercalator molecules have higher binding affinity to dsDNA than ssDNA. Mikkelsen and coworkers investigated this approach by using Co(phen) as a hybridization indicator. The intercalator molecule was accumulated at ss and dsDNA at covalently attached... 

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