Ion Torrent Semiconductor Sequencing Technology

Ion Torrent is the latest generation sequencing technology. Its core technology is the use of semiconductor technology in chemical and digital information to establish a direct link. DNA chain is fixed In the semiconductor chip micro holes, and followed by the incorporation of ACGT. With the incorporation of each base, hydrogen ions are released, which can be detected at the bottom of each hole through the detection of H+. Compared with other sequencing technologies, this sequencing system is simpler, faster and more flexible.

Technical principle:

In the semiconductor chip micro hole, DNA polymerase lets single stranded DNA as template, according to the principle of base complementarity, and synthetise complementary DNA chain. When a base is stretched by a DNA chain, a proton is released, resulting in a local pH change.

The surface of each micro hole in the Ion Torrent semiconductor sequencing chip contains about 1 million DNA molecules. When sequencing, a continuous flow of nucleotides go through the chip micro pores. If the nucleotide is complementary to the DNA molecule in the specific pore, the nucleotide is synthesized into the DNA molecule, and the hydrogen ion is released, and also the PH of the pore solution is changed. After the ion sensor detects the change of PH, chemical information is changed to the digital electronic information. If the DNA chain contains two identical bases, the voltage signal is double. If the base does not match, then there is no hydrogen ion release, and there is no change in the voltage signal. This method belongs to the direct detection of DNA synthesis. Because of less CCD scanning, fluorescence excitation and other steps, the synthesis of the inserted base can be detected in a few seconds, which greatly shortens the running time.

There are Ion SphereTM particles in Micro pores. The particles contain the DNA template, which can release a proton combined with a nucleoside, and finally resulting in pH changes in the micro hole. Sensing layer detects the change of pH, and converts the chemical signal into digital signal.

Main application:

Small genome sequencing (e.g. de novo genome sequencing of microorganisms and viruses, mitochondrial DNA sequencing, etc.)

PCR sequencing (e.g. 16S metagenomics sequencing)

Targeted re sequencing

Genome / full exome validation

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