Advanced Diagnostics using Phononics

Lead Research Organisation: University of Glasgow
Department Name: School of Engineering

Abstract

The research, which will be carried out in the School of Engineering at the University of Glasgow, will underpin a completely new paradigm in the handling of liquids. It involves the control of the mechanical interactions between fluids and microfabricated structures, with acoustic waves. Notwithstanding its potential impact on a wide range of areas (e.g. physics and chemistry), my focus in this Fellowship will be in enabling advanced diagnostics both in remote areas in developing countries and in the developed world, by integrating complex biological sample processing on low cost portable devices.

Acoustic waves carry a mechanical energy that has been successfully used to actuate a wide range of liquid functions. In particular, Surface Acoustic Waves (SAW) propagated on piezoelectric surfaces, using transducers commonly found in electronics, can refract in a liquid, leading to recirculation flows.

I have pioneered and enhanced a technique to control SAW and their interactions with the liquid and particles, enabling more complex manipulations. The new platform is based on micromanufactured, disposable phononic lattices, that scatter or reflect the acoustic waves in a frequency dependent manner. These structures shape the acoustic waves, in a manner analogous to that of holograms shaping light.

The structures rely on mechanical contrast when holograms are based on refractive index. Geometric aspects of the hologram's design provide colours of different frequencies; here, the phononic lattice geometry determines the frequency at which the sound is scattered. The different frequencies of ultrasound interact with different phononic structures to give different functions, providing a "tool-box" of different diagnostic processes (sample processing, cell separation, detection), which, when combined, form a fluidic circuit, a complete diagnostic assay.

Contrary to the established microfluidic systems used in point-of-care devices, which rely on flow through channels to carry out different functions at different positions within the channels, I will design, fabricate, characterise and use new phononic lattices to combine different functions in the frequency domain, on a stationary sample.

Others involved in the research include Professor Miles Padgett (School of Physics), Professor Andy Waters (Welcome Centre for Molecular Parasitology), Dr Andrew Winters (Consultant in Sexual Health & HIV Medicine and Joint Clinical Director at The Sandyford Clinic, NHS Greater Glasgow and Clyde) and Dr Mhairi Copland (Paul O'Gorman Leukaemia Research Centre and the Beatson Cancer Research.

My research will have three potential outcomes in diagnostics and sensing, namely the development of new Microsystems technologies for:

1. Drug resistant malaria diagnostics. I will develop phononic geometries to carry out a complete nucleic acid based test, including sample preparation, amplification, and detection in whole blood. These will be fabricated in low cost materials (e.g. glass, composites) and could transform malaria diagnostics in the Developing World.
2. Multiplexed detection of a panel of sexually transmitted diseases, working with the NHS. The ability to perform complex sample preparation has the potential to integrate multiplexed analysis in an expert system, where instead of a diagnostic test centered around a pathogen, the test has the capability to analyse a set of symptoms, a decisive shift in diagnostics.
3. Stratification of leukemia cells' aggressiveness. I will explore how the combination of the cells mechanical information probed using acoustics, and coupled with electrical information on cell membranes, could enable a multidimensional analysis of cells.

This research will have the potential to create devices to carry out diagnostics anywhere.

Planned Impact

The programme will create impact within society through improvements in diagnosis and treatment of disease, where this is presently constrained by difficulties associated with the complexity of automation of sample preparation (from blood, saliva or other biological fluids). This situation arises both in the Developed World (in primary care, point of care or in home diagnostics) or in the Developing World (in the field or in regions where infrastructure is limited). This impact will be realised in practice through the development of commercial devices and intellectual property, the delivery of which will have additional economic impacts.

Academics and commercial organizations will benefit in the short term. Academics involved in my immediate research environment will benefit from my improved understanding of this technology. These include a wide range of individuals, namely Professor Miles Padgett (School of Physics), Professor Andy Waters (Molecular Parasitology), Dr Andrew Winters (Consultant in Sexual Health & HIV Medicine and Dr Mhairi Copland (Leukaemia Research Centre and the Beatson Cancer Research). A broad range of other academics will also benefit including those involved in diagnostic instrumentation, microfluidics, microsystems, acoustics and sensors, as they will become aware of a new paradigm by which samples can be manipulated.

Commercial organisations, including diagnostic companies and microfluidic foundries will also benefit in the short term, as they discover how new tools can be used in a wide range of future applications, not only associated with diagnostics but also therapeutics and drug delivery. These will include UK based large diagnostic companies such as Alere or smaller SMEs, such as Mode Dx or Epigem. If we are able to spin-out this technology, other immediate beneficiaries will include those employed in the company.

In the longer term, as the use of phononics becomes more widespread, the range of academic users will grow and undoubtedly the methods will find broader applications outside of the fields associated with biomedical technologies (including for example environmental science and chemical processing).

Similarly, in the longer term, companies involved in the development of new diagnostic tests in the Developed World will benefit from a new technology that enables low cost, high value molecular diagnostics in crude samples. Beneficiaries will also include charitable foundations (such as the WHO, FIND and The Bill & Melinda Gates Foundation), who deliver healthcare in the Developing World, and who all will be able to perform rapid diagnostics in the field.

The relevance of the work to the proposed beneficiaries in industry, the health services and the patients is significant. Whether in the Developed or the Developing World, the most obvious way in which the cycle of infection and transmission can be broken is through rapid diagnosis, and treatment at the point of care (when the patient is present). To illustrate this, it is relevant to consider sexually transmitted infections in urban environments in the Developed World. Current testing takes too long and the patient leaves the clinic before the diagnosis is made and treatment is administered. After leaving a clinic, only 4/10 patients return, despite the use of electronic messaging/texting. Similar situations arise in the Developing World, where the patient may travel for many hours for diagnosis and may not have the opportunity to return for treatment, before the cycle of infection continues. The benefits of a rapid technology, that is low cost and able to provide detailed information, at the point of care, is significant for healthcare workers, patients and populations as a whole. It is considered that rapid point of care molecular diagnostics will underpin any strategy for infectious disease elimination, whether this be in sub-Saharan Africa or Glasgow.

Publications

10 25 50
 
Description In this project we have utilised phononic structures based on numerical simulations for the low power fragmentation of DNA, with applications in the sequencing of infectious diseases. The power involved is less than 5 W (i.e. much less that that needed by a laptop) and the devices can be made using polymeric structures or micromaching silicon. These have been integrated with custom built electronic controllers to regulate sample heating.

The second strand to the ultrasonics worked looked at the mechanical and biomechanical properties of composite materials using the 2-D non-linear mixing of surface acoustic waves both through modelling and tested using a series of biological fluids and tissues.

As our understanding of how the phononic and acoustic structures we could make evolved, as a third strand to the acoustic work, we have developed a novel lens-free microscopy system that utilises acoustically actuated 'nanolenses' to enable the detection of objects on the scale of a few nanometres; this and similar work to detect the rheology of materials on the the ultra-low volume scale may have applications in the future for biological studies too.

This increase in our ability to control acoustic patterns at small length scales (in this case the microscale), led to the fourth aspect of the phononics effort, that of nebulisation of fluids to make well defined aerosols containing therapeutic drugs, being developed to the extent that we have been able to form a company, Nebuflow, which has received a number of innovation awards and is currently in the process of securing further funds to take this to the next stage of product development.

Finally, an additional theme of this work that we have been able to pursue has involved the development of diagnostic tests for diseases such as schistomiasis and malaria, with the LAMP and optical assays we have developed now being tested in the field, in Uganda and other LMIC countries.
Exploitation Route Work associated with the SAW nebulisation of liquids for drug delivery and fragmentation has been submitted for two patents. It is being considered for further funding by Vectura and a TSB project with a spin out SAWDx has been funded to explore using SAW techniques in next generation sequencing workflows. In addition, a second company, Nebulflow, has been founded to take forward the nebulisation aspects of this work.
Sectors Healthcare,Manufacturing, including Industrial Biotechology,Pharmaceuticals and Medical Biotechnology

 
Description Filed patents have formed the basis for the evolution of business plans associated with spin-out companies SAWDx and Nebulflow, and further collaborations with companies such as IPGroup, Vectura and others.
First Year Of Impact 2016
Sector Healthcare,Manufacturing, including Industrial Biotechology,Pharmaceuticals and Medical Biotechnology
Impact Types Economic

 
Description EPSRC GRCF
Amount £1,585,505 (GBP)
Funding ID EP/R01437X/1 
Organisation Engineering and Physical Sciences Research Council (EPSRC) 
Sector Public
Country United Kingdom
Start 02/2018 
End 01/2021
 
Description Innovate
Amount £1,000,000 (GBP)
Funding ID INNOVATE (81169-5100397) 
Organisation Innovate UK 
Sector Public
Country United Kingdom
Start 03/2017 
End 08/2018
 
Title Acoustic suppression of the coffee-ring effect. 
Description  
Type Of Material Database/Collection of data 
Year Produced 2015 
Provided To Others? Yes  
 
Title Assessment of Biocompatibility of 3D printed Photopolymers using Zebrafish Embryo Toxicity Assays 
Description  
Type Of Material Database/Collection of data 
Year Produced 2015 
Provided To Others? Yes  
 
Title Branched Hybridization Chain Reaction - using highly dimensional DNA nanostructures for multiplexed molecular diagnostics 
Description The dataset contains all the primary data used in the work presented in our publication, including pictures and quantified signals. 
Type Of Material Database/Collection of data 
Year Produced 2017 
Provided To Others? Yes  
 
Title Breaking the symmetry of momentum conservation using evanescent acoustic fields 
Description  
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes  
 
Title Capillary-based multiplexed isothermal nucleic acid-based test for sexually transmitted diseases in patients 
Description  
Type Of Material Database/Collection of data 
Year Produced 2016 
Provided To Others? Yes  
 
Title Confinement of Capillary Waves to control Aerosol Droplet Size and Dispersity 
Description In addition to the data available on this page, the video data stored in zip files: 400um.zip (2.3 GB), 800um.zip (3 GB) , 1500um.zip (5.2 GB) and sessile.zip (162 GB) are available by request as they are too big to download. 
Type Of Material Database/Collection of data 
Year Produced 2017 
Provided To Others? Yes  
 
Title Frequency dependence of microflows upon acoustic interactions with fluids 
Description This is the raw data for the results presented in the manuscript. It includes images, simulation models and csv files. 
Type Of Material Database/Collection of data 
Year Produced 2017 
Provided To Others? Yes  
 
Title Hyperelastic Tuning of One Dimensional Phononic Band-Gaps Using Directional Stress 
Description This is the raw data for the results presented in the manuscript. It includes m, fig and mat files (Matlab file format). 
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes  
 
Title Lipid topology and linear cationic antimicrobial peptides: a novel mechanistic model 
Description  
Type Of Material Database/Collection of data 
Year Produced 2017 
Provided To Others? Yes  
 
Title Multi-Reflection Polarimetry in Microfluidics 
Description The field of microfluidics promises new portable, low-cost sensing systems, as well as the capabilities to measure the physical or chemical properties of precious samples, for which only small volumes are available. However, when using microfluidic channels with millimeter to micron scale dimmensions, together with optical sensing methods, these configurations result in short path lengths over which the signal can be acquired. Whilst polarimetry would greatly benefit from using small volumes, providing important information on the structure of chiral biomarkers in life sciences, the small interrogation volumes associated with the use of minute samples decreases the numbers of molecules in the light path that cause an optical rotation, and so reduces the sensitivity of the technique. Here we show that when an optical beam, passing through a chiral sample, undergoes multiple reflections from suitably aligned and configured external micromirrors, the usual cancelling out of the optical rotation that occurs when the rotated polarized beam is passed back through a solution following reflection at a single mirror can be negated. This enables the chirality of molecular species present in a microfluidic sample to be measured with increased sensitivity. This approach was validated experimentally using solutions of D-(+)-glucose as a model system, by investigating the effect of multiple reflections of a linearly polarized He-Ne laser beam and a 403 nm diode laser beam across the microfluidic channel. It was found that there was a 30 fold enhancement in the limit of detection with as few as 11 reflections through the sample. 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? Yes  
 
Title Nonlinear wave interactions in hyperelastic medium 
Description Illustration of nonlinear wave interactions in PVC and nonlinear field development within interaction volume. 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? Yes  
 
Title Origami-based Multiplexed Infectious Disease Diagnostics from Whole Blood 
Description  
Type Of Material Database/Collection of data 
Year Produced 2016 
Provided To Others? Yes  
 
Title Rapid Veterinary Diagnosis of Bovine Reproductive Infectious Dis-eases from Semen using Paper-Origami DNA Microfluidics 
Description This is the raw data for the results presented in the manuscript. It includes images and .csv files. 
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes  
 
Title Ultrasonic waves in uniaxially stressed multilayered and 1-D phononic structures: guided and Floquet wave analysis 
Description  
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes  
 
Title Visualization of surface acoustic waves in thin liquid films 
Description  
Type Of Material Database/Collection of data 
Year Produced 2016 
Provided To Others? Yes  
 
Description University of St Andrews 
Organisation University of St Andrews
Department School of Physics and Astronomy
Country United Kingdom 
Sector Academic/University 
PI Contribution Definition of the problem to be solved, suggested approach and computational resources.
Collaborator Contribution Extended theory, created model and simulations
Impact one paper submitted, two in preparation.
Start Year 2016
 
Description Royal Society Summer Exhibition 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact Showcase for stimulated bone growth using acoustics
Year(s) Of Engagement Activity 2018