Investigation of Bifurcation Effect on Various Microfluidic Designs for Blood Separation.

In this project, a microfluidic device for blood separation will be designed and tested in order to separate plasma from whole blood for diagnostic purposes. The design will be based on previously implemented designs that will be further discussed in the next sections. When designing microfluidic devices, it is essential to consider the different physical phenomena that arise from switching from the macro scale to the micro scale. Parameters such as the Reynolds number and the forces affecting the fluid must be studied in order to produce a suitable and effective design. Finite element methods have been implemented prior to the production of the microfluidic devices. Various geometries/designs have been tested using Fluent ANSYS software. Later on, the successful design was fabricated using micromachining on an acrylic substrate and was tested using simulated blood through of a syringe pump.

Sensitivity Enhancement of Point-of-Care for Cardiac Markers Detection using Micro-Impedimetric Immunosensor Arrays.

This paper describes the development and characterisation of a novel, electrical impedance spectroscopy-based (EIS) immunosensor array for point-of-care applications. EIS is a highly sensitive, label-free, real time technique suitable for single use, point-of-care cardiac marker detection devices. However, the underlying source of the observed change in EIS immunoassay response has not been well characterised or understood. A full understanding of the relationship between target binding and impedance response would significantly advance biosensor design and most probably increase detection limit sensitivity. The development of micro-/nano- structured electrodes for multi-frequency EIS procedure propose substantial benefits over classical macro-structured systems.Countless manipulations of electrode features and inter-electrode spacing will enhance the electrode surface area, increase the charge-transfer resistance and reduce the double-layer capacitance. These in turn give rise to improved signal-to-noise ratios, therefore affording greater sensitivity, lower detection limits and faster detection times.The sensor sensitivity range was within that required for human myoglobin determination, following acute myocardial infarction (heart attack). Real-time MyAb-MyAg interaction monitoring, permitted the determination of the binding events in less than one minute.

Detection of Human Chorionic Gonadotropin (hCG) Hormone using Digital Lateral Flow Immunoassay.

The main goal of this work was to establish a hybrid device incorporating an electrochemical-based transducer on a conventional lateral flow assay strip in order to perform an on-chip fast testing method for the detection of various bio-analyses. In this context, the expected development of the digital lateral-flow immunoassay to be considered a reliable low-cost instrument improves the future of the very simple and flexible approach oflateral-flow assays. It is anticipated to achieve a digital quantitative lateral-flow immunoassay by exploring the electrochemical transducers alongwith recognition elements for digitization of commercially available rapid tests. As a preliminary step, the described technique will be validated using two standard electrochemical measurements (amperometric and impedimetric) across two electrodes fixed onto the surface of LFA strip. The LFA strips were prepared at the factory for pregnancy tests and modified by adding two parallel copper electrodes at the lab. These strips were proven by in-vitro experiments to be reusable lasting for 20-30 multiple days. Further on, the detection of hCG Ab-Ag interaction using these strips was performed. Two different types of measurements, namely amperometric and impedimetric, were used which yielded similar results to those reported in literature with screen-printed micro-electrodes. In addition, different concentrations of NaCl and hCG Ag solution were investigated. However, the expected linear concentration response was obtained. A promising proof-of-concept have been achieved through this study. Further studies are needed to complete the development of fully printed disposable electrochemical devices that are able to either display a digital result directly or transmit data to a mobile phone using RFID/NFC.

A Brain Machine Interface for command based control of a wheelchair using conditioning of oscillatory brain activity.

In this research a new method of wheelchair control using a Brain Computer Interface (BCI) is proposed, in an attempt to bridge the gap between in-lab and real life applications, we believe it would provide a high level control over the BCI instead of the normal low level commands. It is anticipated to emphasis on mu rhythm to provide the control signals. The wheelchair is equipped with a mapping system, which scans the area and provides a map containing information about the user's current location and next possible destinations, then provides an optimized list of possible trajectories to reach the destination. The paradigm allows users to control the interface using motor imagery and issue commands to switch between possible trajectories and then confirm the choice. Commands trigger the motion of the wheelchair to the intended destination using a user selected path with speed up to 0.5 m/s. The interface also allows the user to interact with different robots through a common robotic system. Evaluation results indicate that this paradigm is indeed usable and could lead to promising outcomes.