Ion Torrent platform is recognized as the world’s first PostLight sequencing technology. Instead of using light as an intermediary, Ion Torrent technology creates a new semiconductor chip—with high-density of micro-machined wells to perform biochemical process in a massively parallel way. Each well holds a different DNA template. Beneath the wells is an ion-sensitive layer and a proprietary Ion sensor at the bottom. While a nucleotide is incorporated into the DNA strand, a hydrogen ion will be released. The charge from that ion will change the pH of the solution, which can be detected by the ion sensor and then directly translates chemical signals into digital format.

Compared with other NGS platforms based on optical detection, the Ion Torrent technology creates a direct connection between chemical and digital worlds, enabling fast, simple, flexible, inexpensive and accurate sequencing. This will be undoubtedly the best choice of small and medium-sized projects. BGI currently has dozens of Ion PGM Systems and Ion Proton Systems.

     

                        Figure 1 Sequencing Principle                                    Figure 2 Ion Torrent Platforms

Specifications

 

Ion Torrent PGM

Ion Torrent Proton

Chip Type

PGM 314

PGM 316

PGM 318

Proton I

Proton II
(~July-2013)

# of sensors

1.3M

6.3M

11M

165M

660M

Total output

10-40Mb

100-400Mb

~1Gb

~10Gb

~100Gb

Run time

1-2 hrs

1-2 hrs

1-2 hrs

2.5 hrs

2.5 hrs

Read length

up to 400bp

~200bp

up to 400bp

~200bp

~200bp

Total reads

up to 0.6M

up to 3M

up to 6M

60-80M

240-330M

Table 1. Specifications of Ion Torrent Platform

Technique Features

1. Simple: Simple sequencing chemistry based on semi-conductor technology, without optical detection. Low sample requirement.

2. Fast: Sequencing within 2-3 hours, rapid turnaround time (~2 days) from sample to DNA sequences.

3. Flexible: Flexible scaled chips on PGM and Proton systems for different throughput needs.

4. High Accuracy: 99.97%.

Workflow

Figure 3. Ion Torrent Sequencing Workflow


Applications

1. Small genome sequencing (eg: Microbial de-novo & resequencing; Mitochondrial sequencing)

2. Amplicon sequencing (eg: 16S meta genome sequencing)

3. Targeted resequencing

4. Transcriptome and whole exon sequencing (Ion Proton)

Figure 4. Application fields of Ion PGM & Proton Sequencer