High-sensitivity glass slide for DNA microarray that can immobilise DNA fragments by means of covalent bond is named after highly successful orbiting telescope
Takara Bio in collaboration with US based Mirus has successfully developed the Takara-Hubble slide - a high-sensitivity glass slide for DNA microarray that can immobilise DNA fragments by means of covalent bond - and will commence sales in September this year.
DNA microarrays can effectively monitor a variety of changes in gene expression levels found within various types of cells.
For this reason, DNA microarrays are beginning to be used widely across a range of processes that deal with various biological materials, such as basic research to disease diagnosis.
In order to produce DNA microarrays that can give reproducible data, a substrate that can efficiently and securely immobilise DNA fragments is essential.
The surface of this Takara-Hubble slide possesses an active ester highly reactive to amino groups in three-dimensional manner.
The DNA fragment to which primary amino residue is chemically introduced, or amino-modified DNA, can be covalently immobilised on the substrate with a very high efficiency.
Furthermore, the efficiency of immobilisation of the amino-modified DNA is not influenced by its length, thereby enabling versatile immobilisation of DNA fragments from synthetic oligonucleotides to polynucleotides with several hundred bases.
In addition, the surface negative charge of the glass slide inhibits non-specific absorption of nucleic acids to the substrate, resulting in a drastic decrease of background signals.
These features of Takara-Hubble slide overcome some inconvenience of currently used electrostatic immobilization method: the efficiency of immobilisation varies depending on the size of DNA, and the random ionic interaction between the substrate and DNA raises the noise of signals and consequently reduces sensitivity to detect significant signals.
For example, when 80-base DNA fragments are immobilised on the Takara-Hubble slide, it obtains the signal intensity approximately 20 times higher than that of a conventional ion-binding method.
Even in comparison to competitors' covalent-binding glass slides, Takara-Hubble slide can obtain signal intensity 4-25 times stronger when 300-base DNA fragments are immobilised.
The famous Hubble Space Telescope can observe many phenomena such as stars and galaxies in the far reaches of space at a level of accuracy unrivalled against Earth-based telescopes because it is not affected by Earth's atmosphere.
All the same, the Takara Bio's high-sensitivity glass slide enables detection of very weak signals by the benefit of its low background.
This leads to the association with the Hubble Space Telescope, and hence the name. Takara Bio is manufacturing a wide variety of DNA fragments for DNA microarrays with the company's original method for isothermal DNA amplification (ICAN method).
The company's complementary DNA fragments of human genes are already on the market.
These fragments have the amino group attached, allowing researchers to spot them onto the Takara-Hubble slide without further modification, and easily produce a DNA microarray that has the desired targeted DNA fragments immobilised by covalent bond.
The company hopes to see sales of the Hubble slide exceed 50,000 slides per year (1,500 yen per slide) in three years.
