Integrated Fluidic Circuits (IFCs) for Digital PCR

  • Ramesh RamakrishnanEmail author
  • Jian Qin
  • Robert C. Jones
  • L. Suzanne Weaver
Part of the Methods in Molecular Biology book series (MIMB, volume 949)


The Fluidigm Digital Array IFC is a nanofluidic biochip where digital PCR reactions can be performed with isolated individual DNA template molecules. This chip is part of a family of integrated fluidic circuits (IFC) and contains a network of fluid lines, NanoFlex™ valves and chambers. NanoFlex™ valves are made of an elastomeric material that deflects under pressure to create a tight seal and are used to regulate the flow of liquids in the IFC. Digital Arrays have enabled a different approach to digital PCR, by partitioning DNA molecules instead of diluting them. Single DNA molecules are randomly distributed into nanoliter volume reaction chambers and then PCR amplified in the presence of a fluorophore-containing probe. Positive fluorescent signal indicates the presence of a DNA molecule in a reaction chamber, while negative chambers are blank. IFC technology enables the delivery of very precise volumes of solutions in a simple, fast procedure, utilizing a minimum of sample and assay reagents. The development of the IFC technology and the Digital Array chip has revolutionized the field of biology, and has been utilized in gene copy number studies, absolute quantitation (molecule counting) of genomic DNA and cDNA, rare mutation detection, and digital haplotyping.

Key words

Integrated fluidic circuits Digital arrays Digital PCR 


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Copyright information

© Springer Science+Business Media,LLC 2013

Authors and Affiliations

  • Ramesh Ramakrishnan
    • 1
    Email author
  • Jian Qin
    • 1
  • Robert C. Jones
    • 1
  • L. Suzanne Weaver
    • 1
  1. 1.Fluidigm CorporationSouth San FranciscoUSA

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