Digital PCR is a different approach to nucleic acid detection and quantification. It offers a different method for absolute quantification and rare allele detection relative to conventional real-time quantitative PCR. Digital PCR works by partitioning a sample into many individual real-time PCR reactions; some portion of these reactions contain the target molecule (positive) while others do not (negative). Following PCR analysis, the fraction of negative reactions is used to generate an absolute count of the number of target molecules in the sample, without reference to standards or endogenous controls.

Applications Advantages of Digital PCR
  • Rare allele detection
  • Absolute quantification of gene expression
  • Absolute quantification of viral load
  • Absolute quantification of nucleic acid standards
  • Absolute quantification of next-generation sequencing libraries
  • No need to rely on references or standards
  • Desired precision can be achieved by increasing the number of PCR replicates
  • Highly tolerant to inhibitors
  • Capable of analyzing complex mixtures
  • Provides a linear response to the number of copies present to to help enable analysis of small fold-change differences

The GRCF offers two different digital PCR platforms.  Neither platform is droplet based.  Both involve partitioning the sample into individual partitions, and can be used with a variety of assays, including Taqman and PrimeTime Assays.

Constellation dPCR system

This system injects the sample into a nanoplate, which has individually sealed partitions of fixed sized.  The nanoplates are formatted in a standard 96 well format, making them easily amenable to multi-channel pipetting and faster, familiar workflows.  Partitioning, cycling and reading of the samples all occur on the same instrument in a very streamlined manner.  Multiplexing of up to 5 assays in the same sample is possible, if all are within the digital range at the same dilution.

The nanoplates come in two different formats: 24 well, which has 36,000 partitions and 96 well, which has 8,000 partitions.  The 24 well plates are ideal for looking at rare events, the 96 well plates are great for precisely counting more frequent events.

Pricing*:

 Full platesPartial plate charge
24 well plates$11/well$11/well + $3/empty well
96 well plates$8.50/well$8.50/well + $1.50/empty well

*Please note that pricing is per well.  Samples run in duplicate or triplicate will be charged for each well used.

Other possible fees:

  • New assay condition testing: $75/condition
  • Serum sample preparation: $1/sample

QuantStudio 3D

LifeTechnologies QuantStudio 3D system.  This system spreads the sample onto chips, partitioning the sample into about 18,000 individual wells.  This system is best for very small projects that need a large number of partitions.

Pricing:

$26/chip**

**ThermoFisher recommends running 2 chips per sample.