Microarray detection

A similar type of biotin-dendritic multimer also was used to boost sensitivity in DNA microarray detection by 100-fold over that obtainable using traditional avidin-biotin reagent systems (Stears, 2000 Striebel et al., 2004). With this system, a polyvalent biotin dendrimer is able to bind many labeled avidin or streptavidin molecules, which may carry enzymes or fluorescent probes for assay detection. In addition, if the biotinylated dendrimer and the streptavidin detection agent is added at the same time, then at the site of a captured analyte, the biotin-dendrimer conjugates can form huge multi-dendrimer complexes wherein avidin or streptavidin detection reagents bridge between more than one dendrimer. Thus, the use of multivalent biotin-dendrimers can become universal enhancers of DNA hybridization assays or immunoassay procedures. 

MJ. Schermer, Confocal scanning microscopy in microarray detection, in DNA Microarrays A Practical Approach (M. Schena, ed.), p. 17, Oxford University Press (1999). 

Espina V, Woodhouse EC, Wulfkuhle J et al (2004) Protein microarray detection snategies focus on direct detection technologies. J Immimol Methods 290 121-133... 

Fig. 2. The principles of protein microarray detection strategies, (a) Label-based detection method, (b) label-free based detection methods.

From R. H. Liu, J. Yang, R. Lenigk, J. Bonanno, and R Grodzinskl, "Self-Contained, Fully Integrated Biochip tor Sample Preparation, Polymerase Chain Reaction Amplification, and DNA Microarray Detection." Anal. 

Liu, R. H., Yang, J., Lenigk, R., Bonanno, J., Grodzinski, P., Self-contained, hilly integrated biochip for sample preparation, polymerase chain reaction amplification, and DNA microarray detection, Anal. Chem. 2004, 76, 1824-1831. 

Fang SP, Lee HJ, Wark AW, Com RM (2006) Attomole microarray detection of MicroRNAs by nanoparticle-amplified SPR imaging measurements of surface polyadenylation reactions. J Am Chem Soc 128 14044-14046... 

Zhang X, Rogers M, et al. (2004b) High-throughput microarray detection of olfactory receptor gene expression in the mouse. Proc Natl Acad Sci USA 101(39) 14168-14173... 

Chandler DP, Brown J, CaU DR, Wunschel S, Grate JW, Holman DA, Olson L, Stottlemyre MS, Bruckner-Lea CJ (2001) Automated immunomagnetic separation and microarray detection of E. coli 0157 H7 from poultry carcass rinse. Int J Food Microbiol 70 143-154 Chapman PA, Siddons CA, Zadik PM, Jewes L (1991) An improved selective medium for the isolation of Escherichia coli 0157. J Med Microbiol 35 107-110 Chapman PA, Wright DJ, Siddons CA (1994) A comparison of immunomagnetic separation and direct culture for the isolation of verocytotoxin-producing Escherichia coli 0157 from bovine faeces. J Med Microbiol 40 424 27... 

TABLE 14.7 Fluorescent dyes used in microarray detection... 

Data obtained from microarray detection instruments are expressed in units of fluorescent counts with 16-bit values ranging from 1 to 65 536. It is conunon practice to convert or transform the raw counts into a logarithmic scale. Microarray data transformed into a log scale (0-. 8) exhibit a more uniform distribution than raw signal intensities (1-65536). 

Microarray detection methods In the early days of protein microarray analysis, mostly radioisotope-based labeling was applied, especially for phosphorylated proteins [99]. Later, stable isotope-coded amino acids (SILAC) proved useful in in vivo incorporation to cell cultures [100]. Both methods were very sensitive, requiring only minute sample amounts to reveal protein expression differences [101]. The use of an enhanced chemiluminescence (ECL) technique using X-ray film exposure or a phosphor imager instrument was. 

Roy, E., Stewart, G., Mounier, M., Malic, L., Peytavi, R., Clime, L., Madou, M., Bossinot, M., Bergeron, M.G., Veres, T., 2015. From cellular lysis to microarray detection, an integrated thermoplastic elastomer (TPE) point of care lab on a disc. Lab on a Chip 15 (2), 406—416. Safina, G., Ludwig, R., Gorton, L., 2010. A simple and sensitive method for lactose detection based on direct electron transfer between immobilised ceUobiose dehydrogenase and screen-printed carbon electrodes. Electrochimica Acta 55 (26), 7690-7695. 

V. Espina, E.C. Woodhouse, J. Wulfkuhle, H.D. Asmussen, E.F. Petricoin, L.A. Liotta, Protein microarray detection strategies focus on direct detection technologies. Journal of Immunological Methods 290 (2004) 121-133. 

Label-fi ee strategies provide an alternative route for circumventing the above-mentioned difficulties with respect to protein microarray detection. Currently, relatively few label-fi-ee detection methods such as mass spectrometry (MS) (2,3), surface plasmon resonance (SPR) (4) and atomic force microscopy (AFM) (5,6) are applicable to the microarray format. These label-free technologies require the use of sophisticated tools that are not available in all bioanalytical laboratories. 

---