Sensing platforms

M. Zhang and W. Gorski, Electrochemical sensing platform based on the carbon nanotubes/redox medi-ators-biopolymer system. J. Am. Chem. Soc. 127, 2058-2059 (2005). 

A rather new approach for detecting metal ions with very high sensitivity and selectivity utilizes DNAzymes. DNAzymes are a special class of enzymes formed from DNA nucleotides. Compared to proteins and ribozymes, they are more stable, structurally simpler, and therefore cheaper. As DNAzymes often require metal ion cofactors, they are interesting sensing platforms for these metal ions [149]. 

Aslan K, Wu M, Lakowicz JR, Geddes CD (2007) Fluorescent core-shell Ag Si02 nanocomposites for metal-enhanced fluorescence and single nanoparticle sensing platforms. J Am Chem Soc 129 1524-1525... 

The second group consists of algorithms associated with the pesticide concentration quantification. In this case, the initial data is the processed sensor response for an unknown pesticide concentration and the parameters of the calibration curve (which is derived from preliminary experimental calibration measurements for a range of standard pesticide concentrations) or alternatively, a set of sensor responses obtained by addition of known amounts of pesticide to the analysed sample. This group of algorithms allows the automation of the pesticide quantification, thereby enabling the use of the instrumentation by unskilled personal. This removes the sensing platform from specialised laboratories to the realm of the end-users. 

The latter system has been called an IWAO and the results obtained have demonstrated its suitability to be employed as a sensing platform, which confers versatility, robustness and mass-production capabilities besides high sensitivity on conventional bulk optodes. For these reasons it is going to be described in more detail next. 

Several new approaches to designing semiconducting materials for enhanced chemical sensitivity have been reported very recently [4], In some cases, these materials are intended to enhance the capability of an existing technique. In other cases, the materials are the basis of an entirely new sensing platform. The materials are employed as the current-carrying media in transistors or resistors whose... 

Fig. 2 Schematics illustrating various TIRF-based sensing platforms, (a) The NRL Array Biosensor, modified from [28]. (b) The AWACSS platform, modified from [29]. (c) The Evanescent Resonator (ER) platform modified from [13]...

Moore P, Clayton J (2003) To affinity and beyond. Nature 426 725-731 Budach W, Abel AP, Bruno AP et al (1999) Planar waveguides as high performance sensing platforms for fluorescence-based multiplexed oligonucleotide hybridization assays. Anal Chem 71 3347-3355... 

K. Aslan, J. R. Lakowicz, H. Szmacinski, and C. D. Geddes. Metal-enhanced fluorescence solution-based sensing platform Journal of Fluorescence, 2004, 14, 677-679. 

Aslan, K., Malyn, S. N., Bector, G., and Geddes, C. D. (2007). Microwave-accelerated metal-enhanced fluorescence an ultra-fast and sensitive DNA sensing platform Analyst 132 1122-1129. 

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