DNA-based sensors

Liu CW, Huang CC, Chang HT et al (2009) Highly selective DNA-based sensor for lead(II) and mercury(II) ions. Anal Chem 81 2383-2387... 

DNA base sensors for detection of biological agents have the advantages of high sensitivity, selectivity, ability to operate in turbid media, and to be amenable to miniaturization (Shah and Wilkins 2003). The biological agents include bacteria, viruses, and toxins that may be aerosoled deliberately in air, food, or water to spread terrorism and cause disease or death to humans, animals, or plants. 

The DNA-based sensors should have a rapid response time and should be quantitative, sensitive, suitable for automation, cost effective, disposable and solve analytical problems in a wide range of industrial contexts in order to be commercially viable. The developments attained so far by different transducing systems are going to be reviewed. 

Application areas for DNA biosensors include the detection of chemically induced DNA damage by toxic compounds and the detection of pathogenic microorganisms through the hybridization of species-specific DNA sequences. However, this section will only concentrate on the development of DNA-based sensors for toxic compound detection as microorganism detection is not covered in this chapter. 

The electrochemical single or double stranded DNA sensors are usually proposed as screening devices for monitoring samples that may contain toxic compounds but not endorsed as toxicity tests. If the samples are positive then better care should be taken to handle and analyze these samples using other toxicity tests. DNA-based sensors have seen great expansion in their use as tools for detecting toxic compounds,... 

TSM sensors can also be used as DNA-based sensors. Okahata et al. [17] studied the use of... 

Figure 19 Schematic presentation of poly(thiophene)-/DNA-based sensors.

TSM sensors can also be used as DNA-based sensors. Okahata et al. [28] studied the use of oscillatory driven 9 or 27 MHz quartz to quantify DNA-DNA and DNA-protein interactions. They used quartz with one side specifically coated and the other side rubber cased, which was dipped into a stirred and thermostated solution of the target. Binding amounts were evaluated quantitatively as mass per unit area. Effects of probe immobilization tech-... 

Vanickova, M. Labuda, J. Buckova, M. Surugiu, L Mecklenburg, M. Danielsson, B. Investigation of catechin and acridine derivatives using voltammetric and fluorimetric DNA-based sensors. Collect. Czech. Chem. Commun. 2000, 65,1055-1066. 

Y. Han, A. Offenhauser, and S. Ingebrandt, Detection of DNA hybridisation by a field-effect based sensor with covalently attached catcher molecules. Surf. Interface Anal. 38, 176-181 (2006). 

The advantageous properties of PNA-based biosensors represent an appealing alternative to DNA and aptamer based sensors under some circumstances. They offer advantages of increased sensitivity, selectivity, and stability, therefore they present valuable alternative to DNA/aptamer based sensors but have problems associated with solubility and synthetic procedure. 

Recently, an impressive number of inventive designs of DNA-based electrochemical sensing are emerging. These types of sensors combine nucleic acid layers with electrochemical transducers to produce a biosensor and promise to provide a simple, accurate and inexpensive platform for patient diagnosis. 

Wilson, J. N., and Kool, E. T. (2006). Fluorescent DNA base replacements reporters and sensors for biological systems. Org. Biomol. Chem. 4, 4265-4274. 

Fig. 3 Electrochemical aptamer-based sensor of redox-tagged DNA against specific targets, (a) When the aptamer comes in contact with a small molecule, in this case cocaine, it folds, and the redox tag is brought closer to the electrode, increasing the current, (b) When the aptamer comes in contact with thrombin, the tag moves away from the surface, decreasing the electrochemical signal. Reproduced from [85] with permission. Copyright Langmuir, 2007...

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