Stimuli-responsive gel based microfluidic switch

Lead Research Organisation: Northumbria University
Department Name: Fac of Engineering and Environment

Abstract

Elastic instabilities such as buckling, wrinkling and creasing of surfaces, and snapping transitions have historically represented mechanical failure in thin films. However, this does not have to be the case and elastic instabilities, particularly on soft polymer surfaces, can provide reversible control, sensing or actuation in response to well-defined signals or changes in their environment. In previous work, I have shown that surface instabilities can be electrically triggered on a gel surface supported by specifically designed underlying electrodes. The demonstrated actuation required a low voltage of 2 - 4 V. (Adv Mater. Vol 25, 2013) and a rapid actuation was also obtained with response times less than 1 second. This project uses the above insights together with my established understanding and experience in surface instability (mechanics) and materials science to produce a robust electric voltage controlled switch to regulate the liquid flow in a micro-channel.

Practically, the project will focus on understanding a hydrogel based micro-system that will allow quantitative determination of the following: i) the conditions under which buckling occurs and how the onset of buckling depends on the materials properties of the soft surface, the environmental parameters (Ionic values, temperature, pH values) and the electrode geometries; ii) how the morphology of buckling relates to the materials properties of the soft surface, the initial swelling state prior to the actuation, and the electrode geometries; iii) how to trim the buckled shape of the gel layer to effectively control the fluid flow in a micro-environment. Using the understanding from these experiments, a responsive gel based switch will be developed to dynamically regulate the liquid flow in a micro-channel.

The work of this project is cross disciplinary and includes mechanics, materials science and micro-engineering. A range of materials innovations will be used from lithographically produced structural electrodes to gel chemistry. The passive valve technology with an 'on-demand' actuation described in this project is situated in a broad scientific context (chemistry, applied physics, chemical-physics, micro-engineering, chemical engineering, and electro-chemistry). The project will provide the understanding needed to allow future development of novel micro-fluidic devices with high integratibility and automation of liquid flow.

Planned Impact

1.Knowledge and Techniques
Using responsive materials-based passive valves to regulate fluid flow has the potential to bring a high degree of integration and automation to micro-fluidic device design, by reducing additional macroscopic moving parts and creating an easy-to-integrate platform with microelectrodes on a silicon substrate. The scientific and technical key to the proposed method is to electrically actuate an elastic buckling instability to translate in-plane strain energy into out-of-plane displacements/deformation of the gel. The project is based on an existing scientific phenomenon - surface instability, whose fundamental science has been understood during the last decade. New knowledge on the electro-actuation of surface buckling will lead to a better understanding of how to control surface instabilities, thus this approach will greatly accelerate translation to industrial products. From a wider technological perspective, the electro-buckling induced passive valve technique in this project can offer rapid switching to control flow in a micro-channel. It will provide a proof of concept for a high performance integrated microfluidic system as a key unit, in terms of the improved efficiency, low cost, and improved automation. Creating a method to integrate a passive valve by adopting electro-active materials is promising for controlling fluid flow within multifunctional chip devices, with potential development of the products in biology, tissue engineering, chemical engineering, etc.

2.Economic Impact (Direct and Indirect User Collaborations)
A key priority for the UK economy is the development of high-value and specialist manufacturing, underpinned by research which is often inherently multidisciplinary and disruptive. My industrial collaborator Reece Innovation, part of Reece Group Ltd (including Pearson Engineering, Responsive Engineering Group and Velocity UK Ltd), is focused on developing innovatively engineered products for new markets. The companies in the wider Reece Group have interests in subsea, oil and gas, and defence technologies, all of which have products related to the areas of materials science and micro-engineering in this project. Reece Innovation is based in Newcastle and develops long term engagements with Universities rather than single project collaborations. Our partners' global network of clients and suppliers will ensure the project has international reach and impact. Reece Innovation will bring industrial insight to the project and ensure benefits from any IPR can be quickly identified and exploited. They are also potential partners for future spin-off projects funded directly (under non-disclosure agreements), via Innovate UK/Technology Strategy Board (via KTPs or otherwise) or with other partners in, for example, EU Horizon 2020 projects. Where there are no concerns relating to IPR/NDAs, I will publicize and disseminate work via presentations at KTN events, publication of research, and presentation at national/international conferences.

3.People Pipeline and Public Engagement
The training of the postdoctoral researcher and a university funded PhD student with skills relevant to high value manufacturing will benefit both the individuals and UK industry. The experience gained will include (i) clean-room techniques, (ii) materials, (iii) measurement and instrumentation, (iv) microfluidics, (v) mechanics, and (vi) device design and fabrication. They will receive training in public understanding and engagement, and will be involved in exhibition and outreach work through Think Physics (https://www.northumbria.ac.uk/about-us/academic-departments/physics-and-electrical-engineering/thinkphysics/) from an early stage. This will benefit the individuals and also attract wider interest from the public by promoting the spirit of science and highlighting everyday impacts which arise from this research.

Publications

10 25 50
 
Description The significance of this new strategy to configure harmonic surface pattern is illustrated by its selection as a cover for Advanced Functional Materials. It won a Eureka and Discovery prize in EPSRC science photo competition 2016 (media presses in Guardian, NECONNECTED,THE GLOBAL AND MAIL) and a student presentation award (2017) and a student poster award (2018) at the Society of Chemical Industry-CSCST Conferences.

It also leads an innovative actuator design that undergoes stepwise shape changes to be used in micro-fluidics.
Exploitation Route New RGCI applications and INNOVATE UK bids,
Sectors Energy,Healthcare,Manufacturing, including Industrial Biotechology,Other

 
Description New knowledge on soft lithography and polymer based micro-channel techniques generated in EP/N007921 (TRL 1-3) has been transformed into a successful KTP grant with Palintest in Newcastle (KTP010913), to advance the research at higher TRLs (TRL 5-9), and to develop a micro water analyzer with an expected commercial profit of £48M p.a. from 2025. The work led to the award of a grant from Sanli Ltd to develop novel soft robotic technologies (£70k, 2019) and EPSRC UKFN short research visit grant to Manchester (2019) to collaboratively develop next generation wearable electronics.
Sector Chemicals,Electronics,Manufacturing, including Industrial Biotechology,Transport
Impact Types Societal,Economic

 
Description Innovate UK KNOWLEDGE TRANSFER PARTNERSHIP project
Amount £137,988 (GBP)
Funding ID KTP010913 
Organisation Innovate UK 
Sector Public
Country United Kingdom
Start 07/2018 
End 06/2020
 
Description Kan Tong Po International Fellowship 2019
Amount £2,970 (GBP)
Organisation The Royal Society 
Sector Charity/Non Profit
Country United Kingdom
Start 10/2019 
End 04/2020
 
Description The Royal Society Research grant
Amount £14,600 (GBP)
Funding ID Research Grant-RG150662 
Organisation The Royal Society 
Sector Charity/Non Profit
Country United Kingdom
Start 03/2016 
End 03/2017
 
Description Durham University 
Organisation Durham University
Country United Kingdom 
Sector Academic/University 
PI Contribution Delivery of EP/N007921/1 Stimuli-responsive gel based microfluidic switch
Collaborator Contribution Materials, Access to cleanroom facilities
Impact Early stages of project
Start Year 2015
 
Description Reece Innovation Ltd 
Organisation Reece Innovation Ltd
Country United Kingdom 
Sector Private 
PI Contribution Delivery of EP/N007921/1 Stimuli-responsive gel based microfluidic switch
Collaborator Contribution Materials, test cells and substrates R&D meetings and exploitation advice
Impact Early stages of project
Start Year 2015
 
Description 2016 Conference - British Council Researcher Links - Energy & Environment workshop 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact British Council Researcher Links - Energy & Environment workshop, Xi'an, China, July 2016
Year(s) Of Engagement Activity 2016
 
Description 2016 Conference - The 15th European Mechanics of Materials Conference (EMMC15) 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact The 15th European Mechanics of Materials Conference (EMMC15), Brussels, Belgium, September 2016.
Year(s) Of Engagement Activity 2016
URL http://sites.uclouvain.be/emmc15/
 
Description 2016 Conference - The international polymer network group conference (PNG2016), 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Other audiences
Results and Impact The international polymer network group conference (PNG2016), Stockholm, Sweden, Jun 2016. (TALK)
Year(s) Of Engagement Activity 2016
URL https://www.png2016.conf.kth.se
 
Description 2016 Seminar - Department of CEAM at Newcastle University 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Local
Primary Audience Postgraduate students
Results and Impact Newcastle University, CEAM, Nov. 2016.
Year(s) Of Engagement Activity 2016
 
Description 2016 Seminar - Department of Chemistry at University of Hull 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach Regional
Primary Audience Postgraduate students
Results and Impact University of Hull, Chemistry, Nov.2016.
Year(s) Of Engagement Activity 2016
 
Description 2016 Seminar - Frontier Institute of Science and Technology at Xi'an Jiaotong University 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Xi'an Jiaotong University, Frontier Institute of Science and Technology, Jul 2016.
Year(s) Of Engagement Activity 2016
 
Description 2016 Seminar - School of Mechanical and Aerospace Engineering at Queen's University Belfast 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Queen's University Belfast, School of Mechanical and Aerospace Engineering, Apr 2016.
Year(s) Of Engagement Activity 2016
 
Description 2017 Conference - Materials chemistry 2017 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact A talk to report the findings in this project, Materials chemistry 2017, Liverpool, July 2017. (TALK)
Year(s) Of Engagement Activity 2017
 
Description 2017 Conference - The 24th Annual CSCST-SCI Conference Joint with UKFN SIG symposium 
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 Chair of The 24th Annual CSCST-SCI Conference Joint with UKFN SIG symposium (2017) in Northumbria. Newcastle, UK
Year(s) Of Engagement Activity 2017
 
Description 2017 Seminar - Department of Physics at Nottingham Trent University 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Postgraduate students
Results and Impact Nottingham Trent University, Department of Physics, Janu. 2017.
Year(s) Of Engagement Activity 2017
 
Description 2017 Seminar - Haerbin institute of technology 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact A talk to report the progress in Haerbin institute of technology, Centre for Composite Materials and Structures, Aug 2017. This visit leads to the bid on Newton Advanced Fellowships 2018 Round 1 - NAF\R1\180004
Year(s) Of Engagement Activity 2017
 
Description 2017 Seminar - Shanghai Jiaotong University, 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact a talk in Shanghai Jiaotong University, School of Mechanical & Aerospace Engineering, Apr. 2017.
Year(s) Of Engagement Activity 2017
 
Description 2017 Seminar - University of Edinburgh 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Schools
Results and Impact University of Edinburgh, School of Engineering, Apr. 2017
Year(s) Of Engagement Activity 2017
 
Description 2017 Seminar - Xi'an Jiaotong University 
Form Of Engagement Activity A formal working group, expert panel or dialogue
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact A talk to report the progress in Xi'an Jiaotong University, Frontier Institute of Science and Technology, Aug 2017.This visit lead to the joint application on Researcher Links Workshop Grant: 2017-RLWK9-10834, and International Exchanges Cost share (China) Application- IEC\NSFC\170073
Year(s) Of Engagement Activity 2017
 
Description 2017 Workshop- British Council Researcher Links workshop in Nanjing, China 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Professional Practitioners
Results and Impact A talk for British Council Researcher Links workshop, Nanjing University, China, Sept. 2017. (TALK)
Year(s) Of Engagement Activity 2017
 
Description 2017 conference - MRS Fall Meeting in Boston, US 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Schools
Results and Impact A talk in MRS Fall Meeting 2017, Boston, US, DEC 2017. (Poster)
Year(s) Of Engagement Activity 2017
 
Description IEEE International Flexible Electronics Technology Conference, Ottawa, Canada, Aug. 2018. 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Study participants or study members
Results and Impact Active researchers and students are attended, we are awarded Outstanding paper award for IEEE International Flexible Electronics Technology Conference
Year(s) Of Engagement Activity 2018
 
Description The Silk Road International Symposium for Distinguished Young Scholars, Xi'an, China, Apr. 2018. 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Postgraduate students
Results and Impact Please see the report in https://mp.weixin.qq.com/s/Ck1gCTsx89oPPq5Y0Y55yA
Year(s) Of Engagement Activity 2018
URL https://mp.weixin.qq.com/s/Ck1gCTsx89oPPq5Y0Y55yA
 
Description the 25th annual conference for The Chinese Society of Chemical Science and Technology in Manchester 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach International
Primary Audience Study participants or study members
Results and Impact 3rd presentation award and poster award in the 25th annual conference for The Chinese Society of Chemical Science and Technology
Year(s) Of Engagement Activity 2018