US Patent 11618917 Methods for microbial DNA analysis

Provided herein are methods for isolating nucleic acids from intact cells in a sample of intact cells and cell free nucleic acids. The intact cells and cell free nucleic acids are captured and concentrated within the pores of a silicate matrix in a microporous silicate filter. Within the silicate matrix the cell free nucleic acids are degraded with a nuclease, the intact cells are lysed with the released DNA binding to the silicate, the nuclease treated cell free nucleic acids and contaminants from the lysed are washed from the silicate matrix and the DNA bound to the silicate is eluted therefrom to form an isolated DNA product.