Education: DNA replication using microscale natural convection

Abstract

There is a need for innovative educational experiences that unify and reinforce fundamental principles at the interface between the physical, chemical, and life sciences. These experiences empower and excite students by helping them recognize how interdisciplinary knowledge can be applied to develop new products and technologies that benefit society. Microfluidics offers an incredibly versatile tool to address this need. Here we describe our efforts to create innovative hands-on activities that introduce chemical engineering students to molecular biology by challenging them to harness microscale natural convection phenomena to perform DNA replication via the polymerase chain reaction (PCR). Experimentally, we have constructed convective PCR stations incorporating a simple design for loading and mounting cylindrical microfluidic reactors between independently controlled thermal plates. A portable motion analysis microscope enables flow patterns inside the convective reactors to be directly visualized using fluorescent bead tracers. We have also developed a hands-on computational fluid dynamics (CFD) exercise based on modeling microscale thermal convection to identify optimal geometries for DNA replication. A cognitive assessment reveals that these activities strongly impact student learning in a positive way.

Using design strategies from microfluidic device patents to support idea generation

“…While microfluidic designers may be familiar with some of the strategies shown from prior experiences, the collection of the strategies assisted in systematically expanding the possibility of concepts during idea generation. While opportunities to support microfluidics in classrooms have been proposed (Fintschenko 2011 ; Greener et al 2012 ; Priye et al 2012 ) and microfluidic microfabrication and testing methods to execute design concepts are available (Lee and Sundararajan 2010 ; Ferry et al 2011 ), limited guidance has been provided in the early stages of a microfluidic design process. Using the design strategies can help both novice and practitioners in ideation that can lead to more varied and innovative designs.…”

Topology optimisation for natural convection problems

“…It is quite difficult to find values for the critical Grashof numbers in the literature, especially for complex geometries. However, as qualitative guidance one can make use of the limits predicted for, for example, cylinders , infinite plates or shallow porous cavities .…”

Fractal aggregation kinetics contributions to thermal conductivity of nano-suspensions in unsteady thermal convection

“…It is unclear how the non-equilibrium aggregation alters the heat transfer properties of kinetic NS induced via shear flow or thermal convection often encountered in modern nanotechnology applications22. In modern technology, nano-suspensions used in most engineering applications should meet the various thermal convection requirements, for instance, the shear flow and heat transfer of nano-suspensions in biological tissue, DNA replication and amplification via natural convection processes etc 2324…”