The invention provides a process and kit for serial isolation of DNA and RNA from the same sample. First, a siliceous solid support with preferential affinity for DNA over RNA is used to capture DNA in a lysate of a sample. Next, a siliceous solid support with similar affinity for RNA and DNA is used to capture RNA from the same lysate. The respective solid supports are recovered independent of each other, washed, and their bound nucleotide species are eluted. The invention further provides DNA and RNA prepared using the process in a minimal number of steps employing a minimal number of reagents. As the invention yields DNA and RNA of high quality and is amenable to automation, the invention may be used widely in the healthcare and pharmaceutical industries.
