Recent advances in synthetic biology open up new possibilities in healthcare, agriculture, chemicals, materials, energy, and bioremediation. With approximated 15bn molecular assays performed per year in biological laboratories, the automation of these procedures is a strong demand by laboratory scientists. Digital Biology is the computer aided programming of biological assays using digital microfluidic biochip (DMFB) devices based on electrowetting on dielectric technology. Digital Biology allows for wide scale automation of laboratory procedures in synthetic biology by improving efficiency between 1000 to 100000 fold compared to manual laboratory work, for the first time enabling wide scale rapid prototyping for the iterative creation of biological systems. We want to develop the Droplet Flux Technology for intricate control of droplets on DMFBs. Droplet Flux will be a combination of an online software suit for researchers to plan experiments, an open source operating system for DMFB devices and wetware kits to perform a wide range of standardized bioassays used in synthetic biology. Provided that yet open safety questions around synthetic biology are resolved, a portable device using Flux Technology could be constructed and its use extended for e.g. environmental monitoring in agriculture or point of care diagnostics for regular citizens.
6. 6
Biochips
Can run biochemical applications
In-vitro diagnostics
Drug discovery
Biotech
Ecology
Digital microfluidic biochip
7. 7
Motivation for biochips
*This slide was created by prof. K. Chakrabarty, Duke University. Used with permission.
Automation
Integration
Miniaturization
Automation
Integration
Miniaturization
Automation
Integration
Miniaturization
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What are biochips? Biochips are microfluidic platforms designed to run biochemical applications. Biochips use fluids (saliva, blood, urine) in very small amounts, at nanoscale level, to integrate on-chip all the necessary functions needed to perform a biochemical application.
The focus of my phd work is on a specific type of biochips: the digital microfluidic biochips. The application areas of biochips include: point-of-care testing, biotech, drug discovery, homeland security and many others.
We all have interacted before with the traditional laboratory, when our blood samples would have been taken in tubes, and, if you have the chance to walk in a clean room, you might have seen the more advanced robots used to run biochemical applications. Both of these methods work great.
However, using microfluidic platforms, and in our case biochips, has 3 main advantages: automation: as a consequence we reduce likelihood of error due to human interventation, integration – eliminating the need of additional components, and miniaturization which mean smaller volumes of fluids which results in lower cost (reagents are expensive and some rare sample can also be expensive) and faster completion time of the application (at smaller volumes, the fluidic operations execute faster).
In a DMB, the droplets are moved from an electrode to another by using the electrowetting-on-dielectric (EWOD) principle
[60]. I will explain the principle behind it by showing a transversal view of a biochip. We can see that a droplet is sandwiched between a top ground-electrode
and bottom control-electrodes. When voltage is applied at the side of the droplet, an imbalance is created in the interfacial forces between the electrode, droplet and the filler fluid. As a result,
the droplet moves towards the side where the voltage was applied. For example, in
Fig. 2.2, if the electrode on which the droplet is resting is turned off, and the
left electrode is activated by applying voltage, the droplet will move to the left.
