Power-free nucleic acid extraction device


HIV RNA has been successfully extracted from human blood using a portable device that does not need electrical power to work. The system, developed by researchers in the US, is another link in the chain to enable the accurate monitoring of Aids treatment in countries with limited resources.

The availability of antiretroviral therapy has expanded rapidly in recent years, but the ability to monitor the progress of treatment has not kept up with the pace. Although cheap, qualitative assays are available for the initial detection of HIV infection, quantitative viral load measurements are needed to check if treatment is working. Effective, inexpensive sample preparation that works at ambient temperature and without the need for cold storage is one of the current stumbling blocks in achieving this goal.  

Catherine Klapperich, who developed the device with colleagues at Boston University, Massachusetts, says ‘it allows task shifting of the nucleic acid extraction step to the site of the blood draw.' The system uses low pressure, mechanically driven, hybrid alcohol precipitation and solid phase extraction. RNA is captured in a detachable cartridge, which is then immediately ready for storage and transportation. The nucleic acids can then be stored and easily transferred at ambient temperature to the laboratory for testing, without the need for any further specialist equipment.

Samuel Sia, who develops devices to improve the health of people in developing countries, at Columbia University, New York, US, says ‘[this] first step is one of the most difficult, namely, extraction of the nucleic acids from a clinical specimen in a form that is appropriate for downstream amplification.’

‘An important next step will be to integrate this sample processing component with other modules in order to build a fully integrated test,’ adds Sia. Klapperich’s team has recently finished linking their device with a DNA amplification assay. Next they want to develop it to give a visible readout.

Jens Ducrée, a microfluidic platforms expert at Dublin City University, Ireland, says the work ‘may pave the road towards viral load monitoring at the point-of-care in poor health-infrastructure regions where Aids is epidemic.’


Related Content

GSK drug shines in HIV trial

11 July 2012 Business

news image

HIV–Aids drug candidate dolutegravir outperformed Atripla tablets in Phase III

60 years of innovation

24 February 2011 Feature

news image

To celebrate the international year of chemistry, James Mitchell Crow looks back at some of the discoveries and developments ...

Most Read

Quintuple bond activates small stable molecules

19 September 2014 Research

news image

Exotic complexes suggest route to synthetic feedstock

Computer simulations point to formamide as prebiotic intermediate in ‘Miller’ mixtures

16 September 2014 News and Analysis

news image

Electric field may have provided more than just energy for primordial chemistry

Most Commented

US genomics lead being lost to China

17 September 2014 News and Analysis

news image

NIH senior leaders are sounding the alarm bells, saying the US's pre-eminence in genomics research is under threat

The trouble with boycotts

29 August 2014 Critical Point

news image

Cutting academic ties with a censured state can do more harm than good, says Mark Peplow