Harnessing micro-scale transport processes to gain fundamental insights

Into biophysical processes and develop tools for next generation portable molecular diagnostics

Aashish Priye
Sandia National Lab

Fluid flow arising due to thermal gradients (thermal instability driven convective flows) is quite ubiquitous in nature (oceanic currents, cloud formation, etc.) but they can exhibit unique characteristics at the micro-scale, capable of greatly accelerating biomolecular transport and reactions.  For example, such flows are naturally established over a broad range of pore sizes embedded in deep-sea hydrothermal vents and function as highly efficient conveyors to continually shuttle molecular precursors from the bulk fluid to targeted locations on the solid boundaries. This process enables rapid chemical synthesis at bulk species concentrations several orders of magnitude lower than previously thought possible. Insights from this study have the potential to provide a breakthrough in our understanding of the fundamental biochemical processes underlying the formation of prebiotic molecules – a key unanswered question in the origin of life on earth. On the application side, these flow features can be harnessed to develop novel DNA analysis systems that don't rely on bulky and expensive thermocyclers. The lack of affordable, rapid, and easy to use diagnostic technologies is one of the most critical issues confronting global public health. To address this, I describe rapid and portable nucleic acid detection systems such as convective PCR (polymerase chain reaction), which offers an inherently simple design (similar in principle to a lava lamp) and enables PCR to be completed in 10-20 minutes. Electrical power requirements are dramatically reduced by harnessing natural convection to actuate the reaction. Instantaneous detection and analysis are enabled using an ordinary smartphone camera and dedicated app interface. By combining the benefits and speed of the convective PCR format with the versatility of a smartphone-based detection platform, it is possible to construct an extremely portable DNA analysis system for approximately $50. The ability to deliver performance comparable to or surpassing that of current-generation systems while simultaneously providing orders of magnitude reduction in cost has the potential to greatly expand the use of nucleic acid-based detection assays by moving them out of the laboratory and into settings where they are needed most.

Thursday, January 25, 2018
10:30am
1202 Patrick Taylor Hall