A rapid and simple method for the purification of DNA and RNA from human serum and urine is described. The method uses guanidinium thiocyanate (GuSCN) and silica or diatom particles to lyse cells and bind nucleic acids. The purified nucleic acids are then recovered from the reaction vessel. The method is efficient, requiring less than one hour for purification from 12 different specimens and achieving high recovery rates (usually over 50%) for DNA and RNA. The method is suitable for clinical microbiology applications and allows for the purification of genomic DNA, plasmid DNA, and rRNA from cell-rich sources, such as pathogenic gram-negative bacteria. The method is simple, requires no specialized equipment, and is safe for personnel. The use of silica particles allows for the purification of microgram amounts of DNA and RNA, while diatoms are used for the purification of larger amounts from cell-rich sources. The method is effective for the detection of pathogens using nucleic acid probes and is suitable for use with sensitive techniques like PCR. The method has been tested with various nucleic acids, including DNA and RNA, and has shown high recovery rates and purity. The method is reliable, reproducible, and suitable for routine use in clinical settings.A rapid and simple method for the purification of DNA and RNA from human serum and urine is described. The method uses guanidinium thiocyanate (GuSCN) and silica or diatom particles to lyse cells and bind nucleic acids. The purified nucleic acids are then recovered from the reaction vessel. The method is efficient, requiring less than one hour for purification from 12 different specimens and achieving high recovery rates (usually over 50%) for DNA and RNA. The method is suitable for clinical microbiology applications and allows for the purification of genomic DNA, plasmid DNA, and rRNA from cell-rich sources, such as pathogenic gram-negative bacteria. The method is simple, requires no specialized equipment, and is safe for personnel. The use of silica particles allows for the purification of microgram amounts of DNA and RNA, while diatoms are used for the purification of larger amounts from cell-rich sources. The method is effective for the detection of pathogens using nucleic acid probes and is suitable for use with sensitive techniques like PCR. The method has been tested with various nucleic acids, including DNA and RNA, and has shown high recovery rates and purity. The method is reliable, reproducible, and suitable for routine use in clinical settings.