Urine-derived human genomic DNA (gDNA) has wide application in a variety of disciplines including
clinical medicine, sports, and forensic science. We describe a novel method for gDNA extraction from urine
samples using carboxylated magnetic nanoparticles (CMNPs) as solid-phase adsorbents. Sedimentation
associated with freezing of urine samples significantly reduces cell capture by CMNPs. However, the
addition of 10 mM EDTA and subsequent pH modification (pH 6.0–7.1) can re-dissolve urine sediments.
Purified gDNA ranged from around 0.1 kb to more than 23 kb. PCR using specific primers targeting K-ras,
GAPDH, CYP3A4 and GDF5 amplified 100% of varying sized gene fragments, verifying the high quality of the
isolated DNA. Successful PCR amplifications using DNA isolated from urine samples as small as 50 l were
demonstrated. Enrichment of urine cells and subsequent adsorption of DNA can be achieved with the
same CMNPs, greatly simplifying extraction procedures. The CMNP gDNA extraction technique proved
to be simple, rapid, sensitive and environmentally friendly, with application for routine laboratory use
and potentially within automated urine extraction platforms.