Biochip

Bodovitz S, Joos T, Bachmann J. Protein biochips the calm before the storm. Drug Discovery Today 2005 10 283-7, 2005. 

Wright, G. L., Cazares, L. H., Leung, S.-M., Nasim, S., Adam, B.-L., Yip, T.-T., Schellhammer, P. F., Gong, L., and Vlahou, A. (2000). ProteinChip surface enhanced laser desorption/ionization (SELDI) mass spectrometry a novel protein biochip technology for detection of prostate cancer biomarkers in complex protein mixtures. Prostate Cancer and Prostatic Diseases 2, 264-276. 

Emili AQ et al. Large-scale functional analysis using peptide or protein arrays. Nature Biotechnol 2000 18 393-397. Fung ET et al. Protein biochips for differential profiling. Curr Opin Biotechnol 2001 12 65-69. 

The chemiluminescence and electrochemiluminescence of luminol have been also exploited for the development of enzyme, DNA and immuno-biochips. Different approaches were studied in our laboratory, in which... 

Based on IgG-bearing beads, a chemiluminescent immuno-biochip has been also realized for the model detection of human IgG. Biotin-labeled antihuman IgG were used in a competitive assay, in conjunction with peroxidase labelled streptavidin59. In that case, the planar glassy carbon electrode served only as a support for the sensing layer since the light signal came from the biocatalytic activity of horseradish peroxidase. Free antigen could then be detected with a detection limit of 25 pg (108 molecules) and up to 15 ng. 

In a similar way, the use of oligonucleotide-immobilized beads enabled the realization of DNA sensitive biochips that could be used to detect biotin labelled sequence as 5.108 molecules59. 

Poly(dimethylsiloxane) (PDMS) as an immobilization matrix has been successfully used to design multi-purpose biochips i.e., for either nucleic... 

This new material was used to design biochips based on the electrochemiluminescence reaction of luminol in the presence of enzymatically... 

Multi-parameter enzyme-based biochips could also be obtained by locally adsorbing, at the PDMS-graphite surface, several oxidase enzymes. 

Figure 11. Electrochemiluminescent PDMS-graphite biochip formats (a) nucleic acid-based biochip (b) immunochip (competitive immunoassay).

The current trends toward miniaturization and the need of massively parallel measurements led to the development of biochips. In this area, biocatalyzed and electrogenerated chemiluminescence reactions appear attractive and represent an alternative to fluorescence detection which is still widespread used despite the numerous problems of quantitative measurements and interference fluorescence emission. 

Composite sensing layers, consisting of bioactive molecule-charged beads entrapped in a polymeric structure, have been successfully used to realize multi-purpose biochips for DNA, proteins or enzymes. For all these different biochips, the chemiluminescence and electro-chemiluminescence measurements required only a CCD camera and neither light sources nor optical filters are needed. 

Marquette C.A., Blum L.J., Self-containing reactant Biochips for the electrochemiluminescent determination of glucose, lactate and choline, Sens. Actuators B 2003 90 112-117. 

Optical read out will compete with micro electrode arrays. New developments in array detectors will open new perspectives. Direct optical detection techniques will add new possibilities to bioanalytical applications in addition to fluorescence measurements presently preferred in biochips read out. 

Vo-Dinh T., Cuthun B., Biosensors and biochips advances in biological and medical diagnostics, Fresenius./. Anal. Chem. 2000 366 540-551. 

Vo-Dinh T., Development of a DNA biochip Principle and apphcations, Sensor Actuat B-Chem. 1998 51 52-59. 

Vo-Dinh T., Alarie J.P., Isola N., Landis D., Wintenberg A.L., Ericson M.N., DNA biochip using a pliototransistor integrated circuit, Anal. Chem. 1998 71 358-363. 

Moreno-Bondi M.C., Alarie J.P., Vo-Dinh T., Multianalyte analyses system using an antibody-based biochip, Anal. Bioanal. Chem. 2003 375 120-124. 

Stratis-Cullum D.N., Griffin G.D., Mobley J., Vass A.A., Vo-Dinh T., A miniature biochip system for detection of aerosolized Bacillus globigii spores, Anal. Chem. 2003 75 275-280. 

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