Method for label-free single-molecule DNA sequencing and device for implementing same

摘要

A method and a device for determining a nucleotide sequence are proposed. The method comprises immobilising looped fragments of a nucleic acid and a polymerase on a sensor surface and adding a mixture of unlabelled nucleotides onto the sensor surface. Moreover, in the mixture added, one nucleotide type is present at a much lower concentration compared to the other nucleotides. Time intervals between each of the charge separation events are determined and the mixture addition and the registration steps are repeated. Moreover, at each repetition, the nucleotide type present at a much lower concentration compared to the other nucleotides in the mixture added is changed. The nucleotide sequence of a nucleic acid molecule is determined by the analysis of the time intervals between each of the charge separation events registered, which result from the insertion, facilitated by the polymerase, of said unlabelled nucleotides into the growing nucleic acid chain. The device comprises a matrix having a plurality of sensor cells, and a digital-analog circuit, a microfluidic apparatus for feeding working solutions to the sensors, and data processing and display means.