Microbubble Enhanced Imaging and Therapeutic Delivery

Lead Research Organisation: University of Leeds
Department Name: Physics and Astronomy

Abstract

Microbubbles (MBs) are tiny bubbles of gas about 1/100th of a hair's breadth in diameter and surrounded by a thin elastic shell. When used with ultrasound (US) imaging they provide increased image contrast. Importantly, it is possible to attach molecules to the MB shell enabling them to bind specifically to target cells, for example in tumours. This allows direct imaging of cancers. Furthermore, it is also possible to attach drug payloads to these targeted MBs. These therapeutic MBs can then be targeted directly to the tumour and their drug payload released by bursting the MBs, using a specific US trigger, leading to localised release of drug. Many cancer drugs are highly toxic, which limits their use and can cause extreme side effects. Therapeutic MBs offer the potential for significantly reducing these side effects, whilst allowing for higher dose drug delivery to the tumour. Our focus for this application will be on Colorectal Cancer (CRC), the third most common cancer in the UK. Around 40,700 people were diagnosed with bowel cancer in 2010 in the UK with an estimated 1.24 million new cases diagnosed worldwide in 2008. It is anticipated that as our elderly population increases, CRC will increase in prevalence (www.nice.org.uk) raising important issues relating to treatment in elderly patients balanced with quality-of-life and health economics considerations. Our aim is to deliver cost-effective, less invasive treatments with fewer side effects and improved quality of life for patients.

Our Programme of research addresses several key challenges that need to be resolved to allow the clinical development of MBs as combined therapy and diagnostic agents. In our recent EPSRC Programme we succeeded in building an instrument for the manufacture of MBs (that have a targeting agent and conjugated drug payload). This enabled us to test their ability to target cancer cells and to effectively treat tumours in pre-clinical models. In order to progress our MBs to the point where they could be used for first-in-man trials we need to satisfy regulatory agencies that our MBs are safe, and have clear clinical benefit. We will also need to demonstrate that they are cost effective, if providers are eventually to take-up this treatment modality.

We have developed a two-pronged approach to developing microbubbles for drug based delivery:
1) Many drugs fail to reach clinical trials because, whilst they are potent as drugs, they are difficult to deliver into cells, or tissue because of poor solubility or becasue they are too toxic to use. For this we propose to develop a new integrated screening platform, that will use the combination of MB+ultrasound, for aiding the delivery of such drugs into cells (and tumour models). This will not only allow re-assessment of many existing drugs but will also speed up the screening of new drugs. Through partnership with the Medicines Discovery Catapult we will promote uptake of this technology with pharmaceutical companies and thereby reduce cost for the identification of new drug candidates.
2) We will develop our, patented, MB production instrument to the point where it could be manufactured by an external company for the first-in-human trials. As part of this we need to optimise how we make the MBs, modify how the drugs and targeting agents are linked to each other and address issues such as ease of use, sterility etc. We also need to show that we can eliminate tumours completely using our MB+US approach. By using materials that have been manufactured according to specific standards (GMP), that are suitable for clinical trials, and processes that are in accord with Good Laboratory Practice we will undertake the necessary in-vitro and in-vivo testing required for moving this "Investigational Medicinal Product" to Phase 1 (First in Human) Clinical trials.

Planned Impact

The research outlined here would have a number of short- and long-term beneficiaries. Most directly, and immediately, affected will be those engaged in translational research, especially that involving the training of new PDRAs and PhDs, within Leeds and relevant staff at the Medicines Discovery Catapult (MDC). For these it will serve to reinforce the benefits of following a multidisciplinary approach to targeting medical problems. This project will broaden the base of researchers engaged in therapeutic delivery through a combination of open internal meetings, such as the journal club, and a project seminar programme. All PDRA's engaged in the original project are applying for, or have received, personal fellowships and we are committed to their development as independent researchers.

Outside the University of Leeds there are other beneficiaries, both academic and industrial who will be "users" of the research outputs in the medium-term.
The MDC will lead the application and commercial development of the Integrated Screening Platform, through engagement with pharmaceutical companies to provide a rapid route for enhanced screening of difficult to deliver drugs. This could be of benefit to a broad range of researchers and companies engaged with drug delivery. MDC will also help with the identification of commercial partners for the (re-)design of the Leeds "Horizon" microfluidics platform for MB formulation - appropriate for clinical use. This platform will be of benefit to researchers engaged in targeted imaging and therapeutic delivery, who will have access to a simple low cost routes for on demand production of targeted, drug conjugated MBs.
Dissemination of our research outputs will be achieved through our annual symposium, through publication in high impact journals and via presentations at relevant international meetings and various networking events.

In the longer term this research will lead to new, more effective modes of therapeutic delivery thereby allowing reduced systemic exposure to potent drugs and concomitantly reduced cost and hence will therefore be of interest to big pharma and charitable organisations engaged with improving the treatment of disease. At this early stage we have maintained our contact with a number of large charitable organisations and relevant pharmaceutical companies and will keep these companies informed of our progress during the project as well as welcoming them to our annual meetings.

The ultimate beneficiaries would be clinicians involved in the delivery of, and the general public as primary recipients of, the technology to be developed. These would benefit from improved efficacy of treatment with reduced side effects and overall improvement in the quality of life, and life expectancy. Finally, the reduced drug content and associated severity of side effects should lead to a reduction in the overall cost of treatment, and, thus could benefit taxpayers.

Publications

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McLaughlan JR (2017) Characterisation of Liposome-Loaded Microbubble Populations for Subharmonic Imaging. in Ultrasound in medicine & biology

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Bao P (2017) Controlling transmembrane protein concentration and orientation in supported lipid bilayers. in Chemical communications (Cambridge, England)

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Ye S (2018) Developing Hollow-Channel Gold Nanoflowers as Trimodal Intracellular Nanoprobes. in International journal of molecular sciences

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Ricketts K (2018) Recommendations for clinical translation of nanoparticle-enhanced radiotherapy. in The British journal of radiology

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Nie L (2018) Combining Acoustic Trapping With Plane Wave Imaging for Localized Microbubble Accumulation in Large Vessels. in IEEE transactions on ultrasonics, ferroelectrics, and frequency control

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Ye S (2019) Sub-Nanometer Thick Gold Nanosheets as Highly Efficient Catalysts. in Advanced science (Weinheim, Baden-Wurttemberg, Germany)

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Nie L (2019) High-Frame-Rate Contrast-Enhanced Echocardiography Using Diverging Waves: 2-D Motion Estimation and Compensation in IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control

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Ye S (2019) Developing gold nanotubes as photoacoustic contrast agents in Journal of Physics: Conference Series

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Batchelor DVB (2020) Nested Nanobubbles for Ultrasound-Triggered Drug Release. in ACS applied materials & interfaces

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Paterson DA (2020) Control of Director Fields in Phospholipid-Coated Liquid Crystal Droplets. in Langmuir : the ACS journal of surfaces and colloids

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Abou-Saleh RH (2020) Freeze-Dried Therapeutic Microbubbles: Stability and Gas Exchange. in ACS applied bio materials

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Roach L (2021) Evaluating Phospholipid-Functionalized Gold Nanorods for In Vivo Applications. in Small (Weinheim an der Bergstrasse, Germany)

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Abou-Saleh RH (2021) Horizon: Microfluidic platform for the production of therapeutic microbubbles and nanobubbles. in The Review of scientific instruments

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Roach L (2022) Controlling the Optical Properties of Gold Nanorods in One-Pot Syntheses. in The journal of physical chemistry. C, Nanomaterials and interfaces

 
Title Film / Animation 
Description Lay person description of how the micro bubble will be used to tackle cancer 
Type Of Art Artwork 
Year Produced 2018 
Impact still ongoing 
 
Description Key findings:
1) liposomes attached to microbubbles - and stay in vasculature longer than liposomes alone - this leads to higher dosages reaching tumour
2) microbubbles plus ultrasound led to synergistic / enhanced treatment of tumours compared to same dosages of the drug alone
3) 1) & 2) allowed improved treatment efficacy and dramatically reduced side effects of chemotherapy
4) our work with MDC allowed use to discern the biodistribution of the components of the bubbles and their cargo post treatment - to provide data necessary for clinical trials
4) we have developed microfulidic platforms for testing drug delivery to tumours on chip and reduce the use of animal models
Exploitation Route 1) now in position to go to clinical trial - but need to meet cGMP etc standards
2) application to other cancers
3) application to infection
Sectors Healthcare,Pharmaceuticals and Medical Biotechnology

 
Description The project team took part in NELSA - to aid commercialisation - this process didn't lead to an positive outcome. But a value proposition was been developed to guide on going work. During this, we established a collaboration with Lightox (a Durham based spin-out) and have also established collaborations in Warwick and Cambridge. These led to ~ 6 papers in good impact journals and have generated industrial interest in Renishaw, Cambridge display technologies. We have leveraged over £240,000 for PhD funding on microbubble projects + a further £50,000 project from MDC to support pancreatic organoid development. We raise a further £120,000 to support the development and explore other opportunities related to the project (eg different disease states, instrument design,...) We have leveraged independent funding for 4 PhD (at £80K per studentship). Peyman did a new investigator award taking forward the organoid on-chip work. Working with MDC, Evonik, and surgical colleagues to work up a clinical trial We have sold two microbubble fabrication platforms to Stanford Faculty of Medicine and Erasmus MC - both leading microbubble groups
First Year Of Impact 2020
Sector Education,Healthcare
Impact Types Cultural,Economic

 
Title Cells under stress: An inertial-shear microfluidic determination of cell behaviour - dataset 
Description The deformability of a cell is the direct result of a complex interplay between the different constituent elements at the subcellular level, coupling a wide range of mechanical responses at different length-scales. Changes to the structure of these components can also alter cell phenotype, thus the critical importance of cell mechano-response for diagnostic applications. The response to mechanical stress depends strongly on the forces experienced by the cell. Here we use cell deformability in both shear-dominant and inertia-dominant microfluidic flow regimes to probe different aspects of the cell structure. In the inertial regime we follow cellular response from (visco-)elastic through plastic deformation to cell structural failure and show a significant drop in cell viability for shear stresses above > 11.8 kN/m2. Comparatively, a shear-dominant regime requires lower applied stresses to achieve higher cell strains. From this regime, deformation traces as a function of time contain a rich source of information including; maximum strain, elastic modulus and cell relaxation times and thus provide a number of markers for distinguishing cell types and potentially disease progression. These results emphasise the benefit of multiple parameter determination for improving detection and will ultimately lead to improved accuracy for diagnosis. We present results for leukemia cells (HL60) as a model circulatory cell as well as for a colorectal cancer cell line SW480 derived from primary adenocarcinoma (Dukes stage B). SW480 were also treated with the actin disrupting drug Latrunculin A (LatA), to test the sensitivity of flow regimes to the cytoskeleton. We show that the shear regime is more sensitive to cytoskeletal changes, and that large strains in the inertial-regime cannot resolve changes to the actin cytoskeleton. 
Type Of Material Database/Collection of data 
Year Produced 2019 
Provided To Others? Yes  
 
Title Dataset associated with 'Biochemical fingerprint of colorectal cancer cell lines using label-free live single-cell Raman spectroscopy' 
Description Raw Raman spectra of the average of each single cell in different colorectal cencer cell lines, and preprocessed data used for multivariate analysis. 
Type Of Material Database/Collection of data 
Year Produced 2018 
Provided To Others? Yes  
 
Title Freeze-dried therapeutic microbubbles: stability and gas exchange 
Description Microbubbles (MBs) are widely used as contrast agents for ultrasound imaging and have been shown to enhance therapeutic delivery. However, they are only stable in solution for a few hours after production, which limits their potential application. Freeze-drying provides long term storage, ease of transport and consistency for therapeutic preparations thereby facilitating their use in clinical settings. The ability to freeze-dry therapeutic MBs is an important development in the translation of therapeutic MBs for clinical application. Here we show that it is possible to freeze-dry, and reconstitute, therapeutic MBs (thMBs) that consist of a lipid-coated microbubble with an attached liposomal payload. These thMBs have been produced using a microfluidic approach, with either calcein as a model drug or gemcitabine (gem) encapsulated inside the liposomes. The results show that freeze-dried powder of thMBs can be stored for at least 6 months, and upon reconstitution maintain their structure, composition and drug loading as well as their in vivo echogenicity and stability. We have also demonstrated that this approach offers the ability to exchange the gas core in the bubble to allow thMBs with different gases to be constructed. This approach is advantageous for the translation process of thMBs as it allows precise control of drug and MB concentration and ease of production at the point of care. 
Type Of Material Database/Collection of data 
Year Produced 2020 
Provided To Others? Yes  
URL http://archive.researchdata.leeds.ac.uk/800/
 
Title High-throughput Microfluidics for Evaluating Microbubble Enhanced Delivery of Cancer Therapeutics in Spheroid Cultures - Dataset 
Description This collection of datasets provides the data used to create the graphs throughout the associated manuscript. Data for spheroid trapping efficiency (fig 1b), fluid flow rates (fig 2c) and spheroid viabilities and diameters (figs 3b, 4c, 5b and 6c) have all been provided. 
Type Of Material Database/Collection of data 
Year Produced 2020 
Provided To Others? Yes  
URL http://archive.researchdata.leeds.ac.uk/692/
 
Title Modeling the Mechanical Stiffness of Pancreatic Ductal Adenocarcinoma: dataset 
Description The dataset are of raw images and collated data. The raw images are of bright field images and confocal images of the PDAC spheroid cultures with and without TGF-ß supplement.The collated data are of the size of the cultures, the oscillatory shear rheology data of the mechanical stiffness assessment of the cultures, and results of efficacy of gemicitabine on the mechanically stiff PDAC cultures. 
Type Of Material Database/Collection of data 
Year Produced 2022 
Provided To Others? Yes  
URL https://archive.researchdata.leeds.ac.uk/944/
 
Description Facebook Interview 
Form Of Engagement Activity A broadcast e.g. TV/radio/film/podcast (other than news/press)
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact · Our Facebook promotion reached 195,949 people, with a total of 207,498 impressions and 16,300 "results" - which is people engaging with the post in some way (click throughs, likes, shares, video views etc)

· Over 10,000 views of the Facebook live interview with Steve and Sally, and many great comments saying people will donate. The video reached over 36,000 people
Year(s) Of Engagement Activity 2018
 
Description High velocity fluidics for the production of nanobubbles for medical applications 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Talk at the Leeds organised Microbubble Symposium, talk included work done on the microfluidics that underpins the microbubble generation at Leeds
Year(s) Of Engagement Activity 2015
 
Description Invited Seminar Sheffield University 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Postgraduate students
Results and Impact Dr Peyman gave an invited seminar talk at the School of Physics, Sheffield University
Year(s) Of Engagement Activity 2018
 
Description Invited Seminar talk - Heriot-Watt University, Edinburgh 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Dr Peyman was invited to give a talk on her research at Leeds at Heriot-Watt University in which she included work on therapeutic microbubbles
Year(s) Of Engagement Activity 2018
 
Description Invited Talk - BMUS (British Medical Ultrasound Society) Meeting, York Dec 2016 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Invited talk at BMUS meeting - collaboration with Edinburgh University - through Thunddar Network
Year(s) Of Engagement Activity 2016
 
Description Invited Talk - Vienna 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Invited talk to drug delivery focussed group meeting - AIST Vienna (October 2016)
Year(s) Of Engagement Activity 2016
 
Description Invited Talk International Conference (SPIE Photonics West, San Francisco, USA) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact Invited talk on my independent research at Leeds from the conference chairs in the area of microfluidics for biomedical applications. I spoke about my organ-on-chip research to an audience of approximately 50 international academics and postgraduate students. The talk was followed by a discussion and questions on the research. From giving the talk I have made new contacts at Stanford University and UC Irvine, USA.
Year(s) Of Engagement Activity 2020
 
Description Invited talk: Microfluidic production of micro- and nano- bubbles for medical applications. Microfluidics focus group, Diamond Light Source, Oxford. 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact Invited talk to the microfluidics focus group at Diamond Light Source that prompted discussions on the integration of beams with microfluidics.
Year(s) Of Engagement Activity 2017
 
Description Microbubbles Workshop - Medicine, Not Just About Medics, December 2019 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact 90 students engaged with workshop as part of annual widening participation event, feedback: "the Microbubbles session was without doubt the big hit of the event - it scored really well with students and teachers alike and they enjoyed how fun, engaging and eye opening it was for some too! Comments from students also suggest that the day as a whole was very eye-opening for them, learned more about the breadth of subjects in the area and also found the day very engaging. Following the event a few more students indicated that they definitely now wanted to come to university."
Year(s) Of Engagement Activity 2019,2020
URL https://www.stem.leeds.ac.uk/events/mnjam-2/
 
Description Microbubbles Workshop - Physics Summer School, July 2019 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Schools
Results and Impact Engaged with 30 pupils using Microbubbles outreach workshop as part of widening participation Physics Summer School
Year(s) Of Engagement Activity 2019
 
Description Microfluidic production of micro- and nano- bubbles for medical applications 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Policymakers/politicians
Results and Impact A RSC organised workshop on ultra-fine bubbles. Current standards policy makers were present and the workshop also included debates on the current science of nanobubbles.
Year(s) Of Engagement Activity 2016
 
Description Microfluidics - a versatile platform for bubble generation and functionalisation 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Professional Practitioners
Results and Impact Invited talk at Izon research symposium 2014 in which I spoke about the work on microbubbles for drug delivery, in particular how they are generated in microfludics.
Year(s) Of Engagement Activity 2014
 
Description Microfluidics: A versatile tool for biomedical research 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Invited talk to the 30th Micromechanics and Microdevices European workshop, Oxford University. I gave a talk on the use of microfluidics for a wide range of biomedical applications that I have performed in my research.
Year(s) Of Engagement Activity 2019
 
Description Out reach event at microTAS Dublin 2017 
Form Of Engagement Activity Participation in an activity, workshop or similar
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact MicroTAS is the premier International conference for microfluidics - as part of the week-long conference it organises an outreach event to engage those outside the academic community. The 2017 meeting was held in Dublin and the Leeds microbubble team organised the outreach event.
Year(s) Of Engagement Activity 2017
URL http://www.microtas2016.org/program/outreach/
 
Description Physics Taster session talk 2018 
Form Of Engagement Activity Participation in an open day or visit at my research institution
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact Dr Peyman gave a talk on bubbles for fighting cancer as part of a physics taster day for school students currently choosing University places.
Year(s) Of Engagement Activity 2018
 
Description Pint of Science public talk: Bottoms up to Bubbles: The little big bangs destroying cancer 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact Dr Peyman was asked to give a talk on the bubble research as part of the nationwide Pint of Science series of talks
Year(s) Of Engagement Activity 2018
 
Description Public talk - Science on the microscale: bubble bombs for fighting cancer 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact Dr Peyman was invited to give a talk to the Huddersfield Women's Institute on the bubble research at Leeds
Year(s) Of Engagement Activity 2016
 
Description Public talk - Therapeutic Microbubbles 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact Dr Peyman was invited to give a talk as part of a an afternoon tea raising money for Yorkshire Cancer Research.
Year(s) Of Engagement Activity 2017
 
Description Regional Newspaper ( 
Form Of Engagement Activity A press release, press conference or response to a media enquiry/interview
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Public/other audiences
Results and Impact Two articles in the Yorkshire Evening Post. The first article included full front page cover plus inside article. The second was a small cover/ inside article
Year(s) Of Engagement Activity 2017,2018
 
Description Science on the microscale: bubble bombs for fighting cancer' 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Schools
Results and Impact Dr Peyman to give a talk at girls school in Manchester on Science on the microscale: bubble bombs for fighting cancer'
Year(s) Of Engagement Activity 2016
 
Description Seminar Exeter 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Professional Practitioners
Results and Impact Seminar - Health Sciences
Year(s) Of Engagement Activity 2016
 
Description Seminar York 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Professional Practitioners
Results and Impact Seminar Biological Physics Meeting for Healthcare
Year(s) Of Engagement Activity 2016
 
Description Targeted distribution to over 100,000 alumni 
Form Of Engagement Activity A magazine, newsletter or online publication
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact The work was publicised in emails to over 100,000 alumni. The "Open Rate" for these was an impressive 17%, with 300 alumni also clicking through from there to the Spotlight feature.
Year(s) Of Engagement Activity 2018
 
Description U3A Grantham 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Public/other audiences
Results and Impact U3A talk and discussion - Grantham March 2016
Year(s) Of Engagement Activity 2016
 
Description Youtube video 
Form Of Engagement Activity Engagement focused website, blog or social media channel
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Media (as a channel to the public)
Results and Impact YouTube videos - two different versions of an interview with Steve Evans, and one animation which was put together - have so far achieved 960 views in total. What's more impressive is that the average watch time for these shows that most people are staying with them, rather than clicking away. The Animation is 48 seconds long and the average view is 37 seconds; the Steve Evans interview is 2.13 long and the average view is 1:30.
Year(s) Of Engagement Activity 2018