10-06-2017, 07:14 AM
The notion of a cheap and reliable computer chip look-alike that performs thousands of biological reactions is very attractive to drug developers. Because these chips automate highly repetitive laboratory tasks by replacing cumbersome equipment with miniaturized, microfluidic assay chemistries, they are able to provide ultra-sensitive detection methodologies at significantly lower costs per assay than traditional methods and in a significantly smaller amount of space.
At present, applications are primarily focused on the analysis of genetic material for defects or sequence variations. Corporate interest centers around the potential of biochips to be used either as point-of-care diagnostics or as high-throughput screening platforms for drug lead identification. The key challenge to making this industry as universally applicable as processor chips in the computer industry is the development of a standardized chip platform that can be used with a variety of "motherboard" systems to stimulate widespread application.
Historical perspective
It is important to realize that a biochip is not a single product, but rather a family of products that form a technology platform. Many developments over the past two decades have contributed to its evolution.
In a sense, the very concept of a biochip was made possible by the work of Fred Sanger and Walter Gilbert, who were awarded a Nobel Prize in 1980 for their pioneering DNA sequencing approach that is widely used today. DNA sequencing chemistry in combination with electric current, as well as micropore agarose gels, laid the foundation for considering miniaturizing molecular assays. Another Nobel-prize winning discovery, Kary Mullis's polymerase chain reaction (PCR), first described in 1983, continued down this road by allowing researchers to amplify minute amounts of DNA to quantities where it could be detected by standard laboratory methods. A further refinement was provided by Leroy Hood's 1986 method for fluorescence-based DNA sequencing, which facilitated the automation of reading DNA sequence.
Further developments, such as sequencing by hybridization, gene marker identification, and expressed sequence tags, provided the critical technological mass to prompt corporate efforts to develop miniaturized and automated versions of DNA sequencing and analysis to increase throughput and decrease costs. In the early and mid-1990s, companies such as Hyseq and Affymetrix were formed to develop DNA array technologies.
