Fluorescence-based technology

For reproducible expression analysis and protein quantification MS methods based on isotopic labeling are available. They were designed in conjunction with two or more dimensional chromatographic peptide separation coupled online to MS and require advanced bioinformatics input to analyze the complex data sets in a reasonable time frame. This is also true for the alternative fluorescence-based technology of differential gel electrophoresis (DIGE Fig. 10.6) with tailor-made software which allows statistical validation of multiple data sets. 

Studying the interaction forces between molecules and interfaces by means of atomic force microscopy and fluorescence-based technologies on the nanometer scale will provide valuable information on interfaces. Investigating surface functionalization processes with organic and biomolecular moieties, as well as self-assembly at surfaces, will enable insights into the basic properties of the interfaces. 

Product and services of interest include genomics, proteomics, custom research and services, and instruments, accessories, consumables and software. PerkinElmer proprietary technologies include time-resolved fluorescence which is employed in the sensitive Wallac DELFIA system and Wallac LANCE homogeneous assay system, and fluorescence polarization, [FP]2 , a robust fluorescence-based technique for receptor binding assays that is both fast and easy-to-use. 

As opposed to conventional analytical techniques, optical sensors and biosensors, particularly those employing absorption and fluorescence-based sensing materials potentially allow for measurement through transparent or semi-transparent materials in a non-destructive fashion4, 5> 9 10. Chemical sensor technology has developed rapidly over the past years and a number of systems for food applications have been introduced and evaluated with foods. 

Based apparently on the same principle as described above, suitable but rather expensive kits exploiting monovalent Fab fragments to block endogenous tissue immunoglobulins have also been developed commercially, such as Mouse-on-Mouse (M.O.M. ) Kits by Vector Laboratories (http //www.vectorlabs.com/). Three Vector M.O.M. kits are available. These kits use the same blocking technology and biotin-avidin detection format, but offer a choice of using either an enzyme-based or fluorescent-based visualization method. 

Z. Zhang, K. T. V. Grattan, A. W. Palmer, R. Summers, R. Summan and S. Hughes, Cr LiSAF fluorescence lifetime based fiber optic thermometer and its application in clinical rf heat treatment, in Advances in Fluorescence Sensing Technology (J. R. Lakowicz and R. B. Thompson, eds.), Proc. SPIE 1885, 300-305(1993). 

Considerable effort is being expended toward the development and understanding of fluorescence-based immunoassay technology. A number of factors can be suggested that tend to drive interest in the pursuit of specific immunoassay methods in general, including sensitivity, accuracy, precision, ease of manufacture, capability for a broad... 

Discontinuous approaches are used through necessity in radiometric assays (Oldham, 1993) and in liquid- and gas-chromatography-based protocols (Syed, 1993). Many commercially available kits designed to measure a particular enzyme activity combine absorbance and fluorescence platereader-based technologies with assay protocols that could be done continuously. However, since many users of these kits have little experience in enzymology, assay instructions usually outline a simplified procedure whereby a... 

Viability-based technologies Direct epifluorescent filter microscopy Membrane laser scanning Fluorescence cytometry Fluorescence flow cytometry... 

It is apparent that signal amplification provides increased sensitivity over direct labeling. This is especially true for fluorescent-based assays. One of the most sensitive signal detection technologies is the immunoRCA (Schweitzer et al., 2000). Rolling circle amplificahon (RCA) is combined with antibody detection. RCA involves the amplification of circularized oligonuceotide probes under isothermal conditions by DNA polymerase (Lizardi et al., 1998). With immunoRCA, the 5 primer is attached to the reporter antibody. Initiation of the amplification starts when circular DNA template binds to the attached primer. 

A number of different detection technologies have been established, including label-based and label-free detection systems (Fig. 2). Fluorescence-based methods are the most commonly... 

Fluorescent-based flux or membrane potential assays provide superior throughput compared to traditional electrophysiology-based screening technologies. For fluorescent-based membrane potential assays, however, the response to increasing channel activity can be non-linear due to the inherent non-linear relationship between channel activity and membrane potential (Fig. 4A). This prevents an accurate readout of efficacy and reduces the reso-... 

Turek-Etienne, T.C., Kober, T. P. et al. 2003. Development of a fluorescence polarization AKT serine threonine kinase assay using an immobilized metal ion affinity-based technology. Assay Drug Dev. Technol. 1, 545-553. 

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