Hybridization Analysis of Labeled RNA by Oligonucleotide Arrays

Miniaturization and high-throughput parallel analysis are new concepts entering modern molecular biology. An exciting example of such technology originally developed by physicists and applied to biology is the microchip. The semiconductor industry manufactures silica chips with increasing numbers of smaller and smaller features, which allows incredible numbers of operations within split seconds. The same principle of performing multiparallel operations on a miniaturized solid phase has led to the development of miniaturized arrays of several hundreds of thousands of DNA fragments on a small chip. Arraying of DNA or RNA samples onto nitrocellulose or nylon membranes is a very common analytical procedure in a molecular biology laboratory. DNA chips or microarrays are miniaturized versions of these classical filter-hybridization techniques. With great precision, thousands of DNA fragments or DNA oligonucleotides can be printed onto glass chips or microscope slides. In the case of oligonucleotides, they can also be synthesized directly on coated silica chips.