Terahertz Lab-on-a-Chip for Bio-liquid Analysis

Lead Research Organisation: University of Birmingham
Department Name: Electronic, Electrical and Computer Eng


There is an increasing global demand for new technologies which deliver rapid and accurate medical diagnostics and lead to improved patient outcomes. The biological sensors field has grown dramatically to meet this demand, aided by significant improvements in microfluidics and microelectronics. This revolution in micro-technology has led to the realisation of biological sensors in the form of a lab-on-a-chip (LOC) that can perform one or more lab analyses of minute quantities of liquid samples on a single chip. This analysis can take many different forms such as chemical, acoustic, low-frequency electrical or optical.

The terahertz frequency range (100 GHz to 3 THz) is an emerging area for the electromagnetic analysis of biological systems. For biological liquids, it is capable of probing rotational and vibrational modes present in biomolecule-solvent systems and is also highly sensitive to biomolecular hydration, temperature, binding and conformational states. Despite these significant advantages for sensing, terahertz waves suffer from a relatively long wavelength which limits the smallest detectable object or liquid volume that can be sensed to a size comparable to a wavelength cubed. This size limit, called the diffraction limit, is significantly larger than many objects of interest such as a biological cell.

In this work, we propose to integrate multiple terahertz resonators with a microfluidic system to create a LOC capable of rapidly sensing free-flowing bio-liquids. The resonators are designed to concentrate the measuring electric field down to a volume comparable to a cell size, overcoming the diffraction limit, and permitting the electromagnetic analysis of picolitre quantities of biological liquids and individual cells. This LOC will function as a measurement platform for scientific studies of cells, extremely small quantities of various cell components (e.g. proteins, DNA and RNA) and other biomolecules of interest.

The research programme intends to push the current state-of-the-art in terahertz liquid sensing in terms of sensitivity (10x), minimum sample volume and low-cost fabrication to open up new sensing and diagnostic opportunities in point-of-care diagnosis and clinical applications. While primarily directed towards the analysis of bio-liquids, the lab-on-a-chip devices developed will also prove useful for the analysis of toxic and explosive liquids, as well as gas sensing.

Planned Impact

Society in its broadest sense will benefit from the new sensing technology developed in this research programme. The developed lab-on-a-chip devices have the potential to offer new or improved bio-medical diagnostics, including real-time point-of-care diagnostics. This will likely lead to improved patient outcomes and cost efficiencies with more targeted care.

The global biosensing industry is worth over £23 billion and is rapidly growing. The lab-on-a-chip technology has the potential to lead to economic benefit through the commercialisation of the technology. This would likely be through a start-up company created to exploit the technology or the licensing of the intellectual property to an existing company.

Immediate beneficiaries of the proposed research will be other researchers, both in industry and academia, who work in the fields of terahertz sensing and technology, biosensing and biomedical. The project will create new knowledge both in terms of the technology and the scientific information garnered from studying various cell lines and biomolecules. The creation of a database containing the measured dielectric properties of these biological samples will be of direct benefit to other researchers in the aforementioned fields.
Beyond the lifetime of this research programme, the lab-on-a-chip will serve as a measurement platform for future scientific gas and liquid studies, and with unprecedented sensitivity it will open up new avenues of research.

Finally, the PDRA and PhD researchers who will directly work on this research programme will acquire a unique set of skills for which there is an acute shortage both in the UK and internationally. The multidisciplinary nature and cutting edge technology means that they will be well equipped for their future careers in academia and industry.
Description The major achievements in the first year of the grant are as follows: (1) We characterised the dielectric properties of the cyclic olefin copolymer Topas from 72 GHz to 2.2 THz. This information will be published in the open literature and will be valuable for other other scientists and engineers working on systems and applications in the Terahertz and millimetre-wave bands who wish to make use of this material. (2) We demonstrated that the Topas material may be used for the realization of high quality factor and compact resonators (called photonic crystal resonators) thanks to its low dielectric loss properties. The realised device was at 100 GHz and fabricated using CNC machining.
Exploitation Route Knowledge of the dielectric properties of COC copolymers will open-up future applications and devices in the millimetre-wave and terahertz bands which require a low loss and inexpensive material. This is notable when compared to other semiconductor materials commonly employed e.g. high resistivity silicon. It may find use in components such as resonators, oscillators, waveguides and antennas. The demonstration of a high quality factor resonator will be useful for mm-wave and terahertz systems which require a low phase noise source e.g. communication and radar systems.
Sectors Aerospace, Defence and Marine,Digital/Communication/Information Technologies (including Software),Electronics,Manufacturing, including Industrial Biotechology

Title Research data supporting the publication "High-Q 100 GHz Photonic Crystal Resonator Fabricated from a Cyclic Olefin Copolymer" 
Type Of Material Database/Collection of data 
Year Produced 2022 
Provided To Others? Yes  
URL http://edata.bham.ac.uk/850/