Digital PCR (dPCR) provides precise and absolute quantification of nucleic acids without a standard curve and without dependence on amplification efficiency.
Digital PCR is ultrasensitive; therefore, appropriate for testing allelic variants and targets of low abundance that are below the sensitivity limit of QPCR. It is also very precise, and is a better tool than QPCR when precise determination of the ratio of several nucleic acid sequences is required.
By employing multiple wells per sample, millions of droplets can be analyzed. Samples are partitioned into ‘droplets’ then large quantities (~20,000 of these partitioned droplets are analyzed using microfluidics technology to provide incomparable precision). Only the positive fraction of the sample is detected; therefore, dPCR can detect mutant alleles in circulating tumor DNA, events as few as 0.01% of cells such as L1 insertions, low-level pathogens, and relative expression in single cells.