The NucleoSpin DNA Clean-up XS kit for the concentration and purification of genomic DNA extracts: An alternative to microdialysis filtration

Traditionally, DNA extracts from biological evidence items have been concentrated and rinsed using microdialysis filtration units, including the Centricon^® and Microcon^® centrifugal filter devices. As an alternative to microdialysis filtration, we present an optimized method for using NucleoSpin^® XS silica columns to concentrate and clean-up aqueous extracts from the organic extraction of DNA from biological samples. The method can be used with standard organic extraction and dithiothreitol (DTT)-based differential extraction methods with no modifications to these methods prior to the concentration and clean-up step. Extracts from laboratory-prepared bloodstains, saliva and semen stains have been successfully amplified with both qPCR and STR assays. Finally, the total time to process a set of samples with the NucleoSpin^® XS column is approximately 30 min vs. approximately 1.5 h with the Centricon^® YM-100 filter device.