Microfluidic chip for stacking, separation and extraction of multiple DNA fragments

• A disposable integrated microfluidic device was developed for rapid sample stacking, separation and extraction of multiple DNA fragments from a relatively large amount of sample.
• Extraction of multiple DNA fragments including 200 bp, 500 bp and 1000 bp could be completed in less than 25 min with extraction efficiency of 50% and above.
• DNA fragments with specific size range were extracted from sheared genomic DNA using the developed chip with similar performance achieved to that using traditional method.

A disposable integrated microfluidic device was developed for rapid sample stacking, separation and extraction of multiple DNA fragments from a relatively large amount of sample. Isotachophoresis hyphenated gel electrophoresis (ITP-GE) was used to pre-concentrate and separate DNA fragments, followed by extraction of pure DNA fragments with electroelution on-chip. DNA fragments of 200 bp, 500 bp and 1 kbp were successfully separated and collected in the extraction chamber within 25 min. The extraction efficiency obtained from the chip was 49.9%, 52.1% and 53.7% for 200 bp, 500 bp and 1 kbp DNA fragments, respectively. The extracted DNA fragments exhibited compatibility with downstream enzymatic reactions, for example PCR. The chip was also used to extract DNA fragments with specific size range from sheared genomic DNA and demonstrated similar performance to that using traditional gel cutting method. The whole assay can finish in 32 min, 6 times faster than traditional method.