about OTS-Probes

Quantdetect has prioritized the most frequently identified gene mutations in human cancer based on public databases, literature, and our own prior studies. The intention of this dPCR probe “library” is to simply monitor tumor burden (in the body) by dPCR, instead for serving as a drug companion diagnostic. For instance, TP53 mutations are the most frequently occurring mutations in human cancer, yet the occurrence of these mutations does not indicate a preference for any specific drug therapy. Therefore, TP53 mutations are suitable targets for ctDNA monitoring using good quality dPCR probes. However, to date, dPCR probes have not been available with sufficient quality and variation. Quantdetect has constructed a high-quality dPCR library that includes a number of target mutations for ctDNA monitoring, namely OTS-Probes. Quantdetect continues to expand the OTS-Probes library with additional target mutations.

Many of the OTS-Probes have completed validation for digital PCR using human-derived DNA. In addition, most of the OTS-Probes are designed for the identical digital PCR condition. These features of the OTS-Probes allow for you to run digital PCR without complicated PCR condition optimization, which is reflected in the name of the "Off-The-Shelf".

The “OTS-Probes” can be used for the following digital PCR systems:
BIO-Rad QX200 Droplet Digital PCR system
Thermo Fisher Scientific QuantStudio 3D Digital PCR system
Thermo Fisher Scientific QuantStudio Absolute Q Digital PCR system

Positive control DNA available upon request.

For Researchers

“OTS-Probes” for Research Use Only

  • *The content of the library is subject to change without notice.
  • *“OTS-Probes” is the product developed and manufactured by Quantdetect, Inc., based on the patented technology developed by Iwate Medical University Institute for Biomedical Sciences and transferred to Quantdetect Inc.

about OTS-Assay

The OTS-Assay of Quantdetect has 3 Assays, including scanning, selecting, and monitoring of mutations. Assays can be chosen on an individual or combination basis.


This Assay identifies gene mutations using a sequencing panel against DNA extracted from tissue or pre-treatment blood. Any gene sequencing panel is acceptable, though we do recommend the OTS-Scan system.


This Assay selects up to 4 mutations to be monitored using our QD algorithm based on the result of panel sequencing . Results from any gene sequencing panel are eligible for selecting appropriate mutations to be monitored.


This Assay monitors variant allele frequency (VAF) of a gene mutation in blood as ctDNA. With one of our OTS-Probes, dPCR quantifies the individual unique mutation that might represent less than 1% VAF over the course of cancer treatment. Generally, 1-2 mutations are sufficient to reflect clinical outcome.

Read in manga OTS-Assay

You can check the details of the research and
literature data on the Nishizuka Lab website.

You can check the details of the research and literature data on the Nishizuka Lab website.