Planar Arrays

Planar microarrays are highly miniaturized and parallelized solid-phase assay systems that use a large number of different capture molecules immobilized in physically addressable locations called microspots. These spots, which typically have diameters of less than 250 |im and are arrayed in rows and columns, are where the capture antibody for each assay is deposited. This deposition by physical touching with pins or spraying with piezoelectric tips is a technologically demanding step that was first pioneered in the gene expression industry for detection of nucleic acids by sequence-specific hybridization [4] . This approach has been used to generate antibody arrays consisting of several hundred capture antibodies by depositing them on nitrocellulose-coated microscope slides. Typically, these large arrays have then been probed either by using a direct labeling approach, where the mixture of antigens is fluores-cently labeled; or conversely, a cocktail of second antibodies labeled with a fluorescent tag have been used to complete the sandwich assays. In either case, quantitation was achieved by imaging the spots with a change-coupled device (CCD) camera. The two limiting features of this approach have been (1) the irreproducibility of the spotting approach, where each new array is considered a new lot of material from a quality control point of view; and (2) the high probability of antibody-antibody interactions when greater than 25 antigen-antibody reactions are performed in a shared physical space. The second is a limiting factor for all multiplexed immunoassays and has been considered in the three most popular platforms.

Project Management Made Easy

Project Management Made Easy

What you need to know about… Project Management Made Easy! Project management consists of more than just a large building project and can encompass small projects as well. No matter what the size of your project, you need to have some sort of project management. How you manage your project has everything to do with its outcome.

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