Biosensors proteins

The technique described in Section 11.5.2 above can be employed to create biological signaling units with protein biosensors [62, 63], changing shape upon binding of a ligand—for example, calcium or chloride [64]—and thereby changing relative conformation and FRET efficiency [65], Alternatively, synthetic dyes, which change decay profile in a predictable manner dependent on environment, can be employed. 

Maehashi, K., Katsura, T., Kerman, K., Takamura, Y., Matsumoto, K., and Tamiya, E. (2007) Label-free protein biosensor based on aptamer-modified carbon nanotube field-effect transitors. Anal. Chem. 79, 782-787. 

C.M. Li, W. Chen, and X. Yang, Impedance labelless detection-based polypyrrole protein biosensor. Front. Biosci. 10, 2518—2526 (2005). 

FRET-based protein biosensors have been developed using CPEs as the lightharvesting donors in conjugation of lock-key recognition. Streptavidin is a... 

Liss, M., Petersen, B., Wolf, H. and Prohaska, E. (2002) An aptamer-based quartz crystal protein biosensor, Anal. Chem. 74, 4488 1495. 

Barak, L.S. et al. 1997. A /3-arrestin/green fluorescent protein biosensor for detecting G protein-coupled receptor activation. J. Biol. Chem. 272, 27497-27500. 

Giuliano, K.A., and Taylor, D.L. 1998. Fluorescent-protein biosensors new tools for drug discovery. Trends Biotechnol. 16, 135-140. 

Pham E, Chiang J, Li I, Shum W, Truong K. A computational tool for designing FRET protein biosensors by rigid-body sampling of their conformational space. Structure 2007 15 515-523. 

Ottesen JJ, Huse M, Sekedat MD, Muir TW. Semisynthesis of phosphovariants of Smad2 reveals substrate preference of activated T-beta-RI kinase. Biochemistry 2004 43 5698-5706. Cotton GJ, Ayers B, Xu R, Muir TW. Insertion of a synthetic peptide into a recombinant protein framework a protein biosensor. J. Am. Chem. Soc. 1999 121 1100-1101. 

First binding-protein biosensor immobilized concanavalin A in a polyvinyl chloride membrane on a platinum wire electrode to measure yeast mannan [11]... 

Label-free protein biosensors witnessed great advance in recent years. An impedometric label-free detection was proposed to conduct immunoassay with high sensitivity and specificity [140]. Aptamers that were immobilized on solid substrates received appreciable attention because they have high permanent charge density, which is possibly exploited for label-free detection such electrochemical impedance spectroscopy (EIS) [141]. There are many cases of aptamers-based sensors, which are separately described in Sect. 4.4. 

Siwy et al. demonstrated the utility of a single conically shaped gold nanotube that was embedded in a mechanically and chemically robust polymeric membrane [142]. They reported biofunctionalized conical Au nanotubes, which are potentially useful for obtaining highly sensitive and selective protein biosensors. So et al. introduced a single walled carbon nanotube field effect transistor (SWNT-FET) combined with aptamers as an alternative to the corresponding antibody [143]. 

Figure 34 A protein biosensor based on the aptamer beacon strategy. Thrombin shifts the DNA s conformational equilibrium to G-quadruplex and produces an increase in fluorescence as the donor-quencher groups get farther apart, compared to the stem-loop structure (See ref 63).

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