Technology Development
Micro-fluidics and lab-on-the-chip
These technologies are being developed in conjunction with a grant provided by ESI to the Mechatronics and Precision Control Systems Laboratory of the University of Toronto, Department of Mechanical and Industrial Engineering.)
- Micro-pump
Recent advancements in MEMS technology allow the fabrication of miniature fluidic systems suitable for applications such as drug delivery and biological analysis. In general the use of micro-pumps requires fine precision flow control. Flow rates of a few micro-liters per minute are required for drug delivery such as in insulin delivery for diabetics, where a daily injection of less than a milliliter is necessary to facilitate control of blood sugar levels. Furthermore, precise sample volumes, in the range of picoliters, are often required by miniaturized assay systems for analyzing DNA or biological samples. No micro-pumps are available to provide for these operational requirements. We aim at high accuracy micro-pumps with a flow rate on the order of 1µl/min. - Micro-arrayer
DNA microarraying technology is evolving as a powerful tool in biomedical and pharmaceutical exploration. It uses a glass slide or membrane onto which biological probes (DNA and protein) are spotted in an addressable two-dimensional array arrangement. It is used to monitor the expression of thousands of genes in a single experiment. Current methods of microarray fabrication use pin or jet spray type dispensers that are attached to high-precision robotic handling systems. Such systems require large sample volumes during preparation and spotting, require long processing time, and require high quality robotic systems. To reduce sample usage, decrease the cycle time and introduce portability we aim at a micro-fluidic lab-on-a-chip device for microarray experiments. - Spot assessment in micro-arrays
DNA microarray technology provides tools for checking the expression of tens of thousands of genes simultaneously. This technology is a multistep process requiring strict quality control at every stage to provide reliable analysis. We aim at non-invasive quality assessment of DNA spots on the microarray slides. The technique incorporates piezo-resistive sensing for detecting the presence and alignment of spots. The modular unit for spot assessment includes a membrane and four piezo-resistive elements, and it can detect the location and size of each spot on the microarray slide with sensitivity in the order of tens of picoliters and several microns. - Micro-mixer
Homogeneous mixing of two or more reagents is a requirement in numerous analytical applications specifically in the field of medicine, biology and chemistry. A micro-fluidic network consisting of mixers, valves, pumps, sensors and reservoirs would be able to perform various specialized laboratory analytical operations. This would ultimately lead to savings in costs and resources due to the lower analysis time and lower quantity of reagents required. We aim at rapid mixing and low consumption of reagents that are compatible with various chemical and medical applications, as well as reduction in cross contamination. - Micro Mass Spectrometer
We are aiming at implementation of Mass Spectrometry (MS) and Ion Mobility Spectrometry (IMS) on micro-scale devices; devices with structural components that are millimeter in size and functional components that are tens or hundreds of microns in size. These devices are significantly smaller and have lower operational requirements compared to traditional systems. The microscale mass spectrometer characterizes and identifies ions based on their mass-to-charge (m/z) ratio. The ion mobility spectrometer characterizes and identifies ions based on their mobility in an electric field at atmospheric pressure. Before analysis using MS or IMS, compounds of the sample of interest must be pre-processed, ionized and transferred from solution into the gas phase. This process is called electro-spray. A microscale, chip-based electro-spray emitter has been developed. - Synthesizer and ELISA
Continuous micro-fluidic devices have been used to emulate complex macro-scale fluidic operations (i.e. biological assays) while successfully decreasing their cycle times and reagent consumption. Unfortunately, these devices need powerful pumps to overcome the large pressure losses that occur in small channels, and the use of micro-valves to control flow makes them difficult to fabricate. More recently, discrete (binary) flow devices have been proposed that can manipulate individual droplets on a two dimensional plane. The scale of these devices offers the same advantages as continuous flow devices, but since the flow is not prescribed by the geometry, discrete flow devices are more flexible and easier to fabricate. These devices generate fluid motion by control of surface tension and do not require pumps. We aim to offer a platform for discrete flow micro-fluidics based on electro-wetting on dielectric (EWOD). The same approach is used to create Enzyme Linked Immunosorbent Assays (ELISA) protocols on microscale devices.