MAE 156B: Winter 2014
Portable Thermal Cycler
The polymerase chain reaction (PCR) is essential in the field of molecular biology. Thermal cyclers are used to perform PCR by rapidly cycling the temperature of the DNA sample under study between a set high and low point. Currently, thermal cyclers are costly and large in size, and pose a problem for point-of-care diagnostics in limited resource settings. The goal of this project is to create a machine that is compact and cost effective. Achieving these goals requires careful detail into the design and the selection of parts.
Background
Duplication of DNA by the polymerase chain reaction (PCR) has become the cornerstone of molecular biology. The process of the reaction is shown in Figure 1. Thermal cycling devices capable of rapidly cycling temperatures are ubiquitous in biological research laboratories, but their cost and size remain prohibitive for applications such as point-of-care diagnostics in limited resource settings. One important example is measurement of HIV viral load in Africa.
Figure 1: Typical PCR Cycle
Objectives
-Design and construct a thermal cycler for use with small single samples in plastic microfluidic chips.
-The device should be small (no larger than a shoe box and preferably much smaller)
-Should include a temperature control system adequate for typical PCR reactions.
-If temperature control requires any custom software or firmware on an external device, this should also be included as part of the prototype.
-Results of computer simulations or experiments characterizing the temperature profile are also desirable but not required.
Design Solution
Figure 2: Design Overview of Device
Impact on Society
The need for DNA analysis has proven to be a necessity in settings that are far from ideal i.e., research laboratory settings. Currently, the methods of performing Polymerase Chain Reactions require thermal cyclers that are large and expensive. In rugged settings, the detection of infectious diseases through PCR has become a high concern; one important example is measurement of HIV viral load in Africa. Due to resource limitations, it is unlikely that a researcher would be able to attain a cost and size effective machine that can accurately perform these tasks.
By creating a portable thermal cycler that is durable, cost effective, and reduced in size, point-of-care diagnostics in limited resource settings would be much more viable. Creating a portable thermal cycler that can be used around the world without the concerns of cost or size would allow for researchers to commence with DNA sampling in the most rugged conditions. In the grand scheme of things, a cost effective portable thermal cycler could provide yet another step towards understanding and preventing infectious diseases.