Fluorescent Polymerase Chain Reaction Nanokit for the Detection of DNA Sequence in Single Living Cells.

Here, a fluorescent polymerase chain reaction (PCR) nanokit is established to detect the specific DNA sequence in a single living cell. Different from well-developed protocols to load cell-permeable probes into single cell for recognition, the DNA sequence in a cellular nucleus is sorted into a nanopipette in our strategy. The target DNA sequence is reacted with the PCR kit components in the nanopipette to complete a PCR amplification reaction. SYBR Green prefilled in the nanopipette is intercalated into double-stranded DNA to induce fluorescence emission for real-time detection down to a single copy. An obvious increase in the fluorescence is observed that validates the detection of the target DNA sequence in single living cells. The established real-time fluorescent PCR nanokit could adapt the PCR kit for single cell analysis and thus offers an alternatively general and highly sensitive strategy for the detection of specific DNA sequences in single living cells.