Inkjet Printing Based Droplet Generation for Integrated Online Digital Polymerase Chain Reaction

Anal Chem. 2018 Apr 17;90(8):5329-5334. doi: 10.1021/acs.analchem.8b00463. Epub 2018 Apr 3.

Abstract

We report on the development of a novel and flexible online digital polymerase chain reaction (dPCR) system. The system was composed of three parts: an inkjet for generating the droplets, a coiled fused-silica capillary for thermal cycling, and a laser-induced fluorescence detector (LIFD) for positive droplet counting. Upon inkjet printing, monodisperse droplets were continuously generated in the oil phase and then introduced into the capillary in the form of a stable dispersion. The droplets containing one or zero molecules of target DNA passed through the helical capillary that was attached to a cylindrical thermal cycler for PCR amplification, resulting in the generation of fluorescence for the DNA-positive droplet. After 36 PCR cycles, the fluorescence signal intensity was detected by laser-induced fluorescence located at the downstream of the capillary, followed by a positive/negative counting. The present system was successfully applied to the absolute quantification of the HPV sequence in Caski cells with dynamic ranges spanning 4 orders of magnitude.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cell Line, Tumor
  • DNA / analysis
  • DNA / genetics*
  • Fluorescence
  • Humans
  • Ink*
  • Papillomaviridae / genetics*
  • Particle Size
  • Polymerase Chain Reaction* / instrumentation
  • Printing*
  • Surface Properties

Substances

  • DNA