Towards an effective and accessible chip supported biosensor based on modification of monolayer organisation and fluidity

Lead Research Organisation: University of Leeds
Department Name: Centre for Molecular Nanoscience

Abstract

The biological membrane is a highly organised structure. Many biologically active compounds interact with the biological membrane and modify its structure and organisation in a very selective manner. Phospholipids form the basic backbone structure of biological membranes. When phospholipid layers are adsorbed on a mercury drop electrode (HMDE) they form monolayers which have a very similar structure and properties to exactly half the phospholipid bilayer of a biological membrane. The reason for this is that the fluid phospholipid layer is directly compatible with the smooth liquid mercury surface. The great advantage of this system is that the structure of the adsorbed phospholipid layer can be very closely interrogated electrochemically since it is supported on a conducting surface. In this way interactions with biologically active compounds which modify the monolayer's structure can be sensed. The disadvantage is that Hg electrodes are fragile, toxic and have no applicability for field use in spite of the sensitivity of the system to biological membrane active species. Another disadvantage is that the Hg surface can only be imaged with extreme difficulty. This project takes the above proven sensing system and modifies it in the following way. A single and an array of platinum (Pt) microelectrode(s) are fabricated on a silicon wafer. On each microelectrode a minute amount of Hg is electrodeposited and on each Hg/Pt electrode a phospholipid monolayer is deposited. The stability of each phospholipid layer will be ensured through the edge effect of the electrode. We will use the silicon wafer array to carry out controlled phospholipid deposition experiments which are not possible on the HMDE. We shall also try out other methods of phospholipid deposition. The project will exploit the fact that the microelectrode array system with deposited phospholipid monolayers is accessible for imaging. AFM studies at Leeds have already been used to image temperature induced phase changes in mica supported phospholipid bilayers showing nucleation and growth processes. The AFM system is eminently suitable therefore to image the potential induced phase changes of the phospholipid monolayers on the individual chip based microelectrodes. It is important to do this because the occurrence of these phase transitions is very sensitive to the interaction of the phospholipid layer with biomembrane active species.In addition the mechanism of the phase changes which are fundamentally the same as those occurring in the electroporation of cells are of immense physical interest and a greater understanding of them can be gained through their imaging. We shall also attempt to image the interaction of the layer with membrane active peptides at different potential values. The AFM system will be developed to image the conformation and state of aggregation of adsorbed anti-microbial peptides on the monolayer in particular as a function of potential change. When biomembrane active compounds interact with phospholipid layers on Hg they alter the fluidity and organisation of the layers. This in turn affects the characteristics of the potential induced phase transitions. This can be very effectively monitored electrochemically by rapid cyclic voltammetry (RCV). Interferences to the analysis will be characterised. Pattern recognition techniques will be developed to characterise the electrochemical response to individual active compounds.The project will deliver a sensor on a silicon wafer which has the potential to detect low levels of biomembrane active organic compounds in natural waters and to assess the biomembrane activity of pharmaceutical compounds. The proven feasibility of cleaning the Hg/Pt electrode and renewing the sensing phospholipid layer will facilitate the incorporation of the device into a flow through system with a full automation and programmable operation.

Publications

10 25 50
 
Description 1. Developed a working sensor for screening water for dissolved toxic organic compounds and nanoparticles at technology readiness level (TRL) 4.
2. Formulated structure-activity relationships of both organic compounds and nanoparticle interaction with the membrane sensor element.
3. Imaged the phospholipid sensor element conformational changes within fluctuating electric field using atomic force microscopy and confocal microscopy.
4. Correlated the observed structural changes of lipid in electric field with mathematical simulations of the same and electrochemical measurements of capacitance.
Exploitation Route To commercialise sensor so that it is used in an industrial context. To develop screening sensor for toxins, nanoparticles and pharmaceuticals.
Sectors Environment,Healthcare,Pharmaceuticals and Medical Biotechnology

 
Description The findings from this grant have been used to bring a sensing system from a lab based tool to near-prototype ready to be applied both to toxicity sensing and measuring biomembrane activity of pharmaceuticals. The findings from the grant have interested many outside organisations and SMEs resulting in a number of collaborations and further successful funding.
First Year Of Impact 2012
Sector Environment,Healthcare
Impact Types Policy & public services

 
Description Horizon 2020
Amount € 6,400,000 (EUR)
Funding ID 685817 
Organisation European Commission 
Sector Public
Country European Union (EU)
Start 04/2016 
End 03/2019
 
Description Knowledge exchange grant
Amount £20,000 (GBP)
Funding ID NE/L01274X/1 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Start 01/2014 
End 03/2014
 
Description Leverhulme Research Grant
Amount £300,000 (GBP)
Funding ID F/00/203/Y 
Organisation The Leverhulme Trust 
Sector Academic/University
Country United Kingdom
Start 11/2011 
End 02/2014
 
Description MoD CDE
Amount £40,000 (GBP)
Organisation Defence Science & Technology Laboratory (DSTL) 
Sector Public
Country United Kingdom
Start 12/2013 
End 05/2014
 
Description Technology Strategy Board
Amount £80,000 (GBP)
Funding ID TS/L007835/1 
Organisation Innovate UK 
Sector Public
Country United Kingdom
Start 06/2014 
End 01/2015
 
Description Towards successfully realising the impact of the chip-based phospholipid on mercury (Hg) device as a toxicity sensing system
Amount £96,173 (GBP)
Funding ID NE/M021378/1 
Organisation Natural Environment Research Council 
Sector Public
Country United Kingdom
Start 06/2015 
End 04/2016
 
Title Development of an an electrochemical screen for biomembrane active compounds and particles. 
Description The screening platform consists of a membrane sensor element on mercury (Hg) microelectrode. The electrode is fabricated on a silicon wafer where the Hg is tightly bound to platinum (Pt). Biomembrane active compounds/particles interact with the membrane sensor element modifying its organisation in a specific and selective way. The technology now has a full performance evaluation and rivals any existing techniques for assaying biomembrane activity. The technology is also micronised and ruggedised to operate in a high throughput configuration. 
Type Of Material Model of mechanisms or symptoms - in vitro 
Provided To Others? No  
Impact The most notable impact of this research has been the development of a collaboration with Unilever over the past year. The technology won Special Commendation by Lush Prize (2013) committee for services to the replacement of animals in testing. The research tool formed the heart and basis of the development of the EU funded HISENTS project. The research tool has formed the basis of the Option Agreement between Blueprint Product Design Ltd and University of Leeds and to the writing of three grant applications one of which to InnovateUK has been approved. 
 
Description ALcontrol Ltd 
Organisation ALcontrol Laboratories
Country United Kingdom 
Sector Private 
PI Contribution We have been working with Unilever on a NERC funded Innovation Grant. We have screened 20 compounds for Unilever and are assessing our technolgy in the context of Unilever's methods and in the toxicity sensing area in general.
Collaborator Contribution ALcontrol's contribution is mainly in the form of commenting on the final results.
Impact None as yet.
Start Year 2015
 
Description Analox Ltd 
Organisation Analox Sensor Technology
Country United Kingdom 
Sector Private 
PI Contribution We entered into a TSB funded opportunity with Analox Ltd, MicroLab Devices and PALL to develop a sensor for tricresyl phosphate in aircraft cabins. Our contribution was to develop the sensing technology.
Collaborator Contribution MicroLab Devices administered the programme and carried out some engineering work on the sensing technology.
Impact No concrete outcomes at present. Collaboration was multidisciplinary.
Start Year 2014
 
Description Blueprint Design Ltd (BPDES) 
Organisation BlueFrog Design
Country United Kingdom 
Sector Private 
PI Contribution We have had a series of meetings with the partner describing our research and applications. We took on the partner as the SME beneficiary to our EU H2020 funded HISENTS program. BPDES will lead the dissemination and exploitation work package. We have written three further grant applications with them: EU H2020 SMEinstrument application RAPPONSE submitted last January and two InnovateUK applications one of which has been approved for funding 58695 GBP coming to Leeds as subcontract.
Collaborator Contribution The partner has developed a market survey report for our technology. BPDES contributed to the writing of the three proposals above. BPDES have drawn up an Option Agreement for the IP at present owned by University of Leeds and signed by both partners.
Impact The collaboration is ongoing. Partner has joined EU HISENTS consortium where we are co-ordinators. This program began 1 April 2017. Blueprint and myself have applied for two Innovate_UK awards using the technology. One of these awards has been successful and we are awaiting formalisation. We have also applied for an H2020 SMEinstrument award. In the evaluation we passed all thresholds but did not achieve sufficient ranking to be awarded the grant. We have three more submissions this year to SMEinstrument call.
Start Year 2014
 
Description Formation of HISENTS EU consortium 
Organisation Blueprint Design Company
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation Catalan Institute of Nanoscience and Nanotechnology
Country Spain 
Sector Academic/University 
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation Fraunhofer Society
Department The Fraunhofer Institute for Biomedical Engineering (IBMT)
Country Germany 
Sector Private 
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation Norwegian Institute for Air Research
Country Norway 
Sector Charity/Non Profit 
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation Saarland University
Country Germany 
Sector Academic/University 
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation Slovak University of Technology in Bratislava
Country Slovakia 
Sector Academic/University 
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation Tel Aviv University
Country Israel 
Sector Academic/University 
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation University College Cork
Department Tyndall National Institute
Country Ireland 
Sector Academic/University 
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation University Hospital Bratislava
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formation of HISENTS EU consortium 
Organisation Vienna University of Technology
Country Austria 
Sector Academic/University 
PI Contribution I contacted ten partners in 2015 and together we put together a grant application to H2020 which was successful. The grant programme began April 2016.
Collaborator Contribution Each partner contributed to the application in the form of describing the work that they would do in the proposed project. At present each partner is contributing to the work of the project.
Impact The outputs from this HISENTS project in the form of deliverables and mid-term report have now been provisionally accepted by the EU commission
Start Year 2015
 
Description Formed a consortium with two SMEs and one large company 
Organisation Analox Sensor Technology
Country United Kingdom 
Sector Private 
PI Contribution Prepared an application for the TSB on a direct development of the sensor to screen aircraft cabin air for toxic molecules. Stage 2 of the application to be submitted next week (10/04/2013). On second submission this grant application was successful (December 2014).
Collaborator Contribution Our technology forms the heart of the collaboration. MicroLab Devices are developing a microfluidic system to interface with our technology. Analox are developing the hybrid system to function in the field; ie within aircraft cabins. PALL are acting as end-user by selling the system to aircraft companies.
Impact Only outcome so far is winning a TSB award. The collaboration is multidisciplinary. Leeds are electrochemists. MicroLab devices are microfluidic engineers. Analox package up analytical /sensing technology and PALL manufacture filters and associated items to be used in aircraft.
Start Year 2013
 
Description Formed a consortium with two SMEs and one large company 
Organisation MicroLab devices Ltd
Country United Kingdom 
Sector Private 
PI Contribution Prepared an application for the TSB on a direct development of the sensor to screen aircraft cabin air for toxic molecules. Stage 2 of the application to be submitted next week (10/04/2013). On second submission this grant application was successful (December 2014).
Collaborator Contribution Our technology forms the heart of the collaboration. MicroLab Devices are developing a microfluidic system to interface with our technology. Analox are developing the hybrid system to function in the field; ie within aircraft cabins. PALL are acting as end-user by selling the system to aircraft companies.
Impact Only outcome so far is winning a TSB award. The collaboration is multidisciplinary. Leeds are electrochemists. MicroLab devices are microfluidic engineers. Analox package up analytical /sensing technology and PALL manufacture filters and associated items to be used in aircraft.
Start Year 2013
 
Description Formed a consortium with two SMEs and one large company 
Organisation PALL Europe
Country United Kingdom 
Sector Private 
PI Contribution Prepared an application for the TSB on a direct development of the sensor to screen aircraft cabin air for toxic molecules. Stage 2 of the application to be submitted next week (10/04/2013). On second submission this grant application was successful (December 2014).
Collaborator Contribution Our technology forms the heart of the collaboration. MicroLab Devices are developing a microfluidic system to interface with our technology. Analox are developing the hybrid system to function in the field; ie within aircraft cabins. PALL are acting as end-user by selling the system to aircraft companies.
Impact Only outcome so far is winning a TSB award. The collaboration is multidisciplinary. Leeds are electrochemists. MicroLab devices are microfluidic engineers. Analox package up analytical /sensing technology and PALL manufacture filters and associated items to be used in aircraft.
Start Year 2013
 
Description MicroLab Devices Ltd 
Organisation MicroLab devices Ltd
Country United Kingdom 
Sector Private 
PI Contribution MicroLab Devices, Analox Ltd and PALL joined with Leeds on a TSB programme to develop a sensor to determine tricresyl phosphate in aircraft cabin air. Leeds carried out the bulk of the work developing the sensing technology.
Collaborator Contribution MicroLab Devices administered the programme. MicroLab Devices made some contribution to the engineering systems of the sensing platform.
Impact None as yet.
Start Year 2014
 
Description PALL 
Organisation PALL Europe
Country United Kingdom 
Sector Private 
PI Contribution Leeds, Analox Ltd, MicroLab Devices carried out TSB funded research into a sensor technology to determine tricresyl phosphate in aircraft cabin air. Leeds carried out most of work developing sensor technology.
Collaborator Contribution MicroLab Devices administered the programme and carried out a small amount of engineering work. PALL did some market research on the need for the sensor technology.
Impact None as yet.
Start Year 2014
 
Description Platform Kinetics Ltd 
Organisation Platform Kinetics
Country United Kingdom 
Sector Private 
PI Contribution We applied jointly with Platform Kinetics Ltd (PKL) for an MoD Dstl grant and were successful. This project involved the development of a screener for antibiotic-target binding using membrane electrochemical methods. The idea was also to embed this screener within a microfluidic system.
Collaborator Contribution PKL developed a microfluidic system and automatic interrogation techniques to interface withe electrochemical screen.
Impact The main output of this collaboration is that proof of concept results have shown that the electrochemical screen for broad-based antibiotic binding with targets is entirely feasible. This has led to a collaboration with the funders the Dstl on an application for funding for a PhD studentship. Disciplines involved are: electrochemistry, microfluidics, synthetic organic chemistry and bacteriology.
Start Year 2013
 
Description Unilever 
Organisation Unilever
Department Unilever Research and Development
Country United Kingdom 
Sector Private 
PI Contribution We have been developing a liaison with Unilever over a year. We shall now screen some compounds for Unilever as a cross validation exercise for our technology. This will consolidate our collaboration. We have now been successful and obtained an Innovation grant from NERC started last June to work with Unilever, SEAC assessing how our technology compared with Unilever's in-house procedures.
Collaborator Contribution Unilever have supplied us with twenty calibration compounds. We have had regular communication with Unilever since June last year comparing our data sets. Unilever has given us sight of numerous data sets using different toxicity sensing technologies.
Impact Collaboration is multidisciplinary and joint paper is in preparation
Start Year 2014
 
Title BIOSENSOR 
Description The discovery relates to the deposition of thin mercury films on to fabricated platinum microelectrodes and the deposition of phospholipid monolayers on the mercury .and their use as toxicity sensors. 
IP Reference WO2009016366 
Protection Patent granted
Year Protection Granted 2016
Licensed No
Impact An Option Agreement relating to the transfer of the IP to a SME was drawn up in 2016 leading to the future licensing of the IP to the SME subject to them raising sufficient finance.
 
Title Biosensor 
Description This patent describes a high throughput on line screener for biomembrane activity of organic compounds. 
IP Reference WO2009016366 
Protection Patent application published
Year Protection Granted 2007
Licensed Yes
Impact The IP was licensed to Modern WaterPLC in 2010. The license was revoked in 2012. The main impact of this patent is the forming of successful on-going collaboration with Unilever and also the continuing collaborations with MicroLab Devices Ltd, Analox Ltd and PALL (Europe). The patent technology formed the basis of a recent successful Horizon 2020 bid with 10 other partners due to start April 1 this year.
 
Title Experimental platform for screening pharmaceuticals and toxins for toxicity 
Description Innovation is an electrochemical technology of sensor element on chip-based electrode in flow system which can screen toxins and pharmaceuticals for toxicity. Technology is high throughput and on-line. A NERC Innovation Grant funded this work which finished in April 2016 and was carried out in collaboration with Unilever, SEAC. This platform led to the idea of a mulitmodule platform for screening nanomaterials, toxins and pharmaceuticals for toxicity and formed the basis of a Horizon 2020 application which was successful and began April 2016. 
Type Diagnostic Tool - Non-Imaging
Current Stage Of Development Refinement. Non-clinical
Year Development Stage Completed 2014
Development Status Actively seeking support
Impact No medical impacts realised yet. 
 
Description Public lectures 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? No
Geographic Reach National
Primary Audience Industry/Business
Results and Impact I give yearly lectures at Imperial College about the development of my technology. This stimulates students who wish to innovate themselves. I give talks at national KT meetings on the history of my technology and engaging with the industrial sector.
Year(s) Of Engagement Activity 2013,2014,2015,2016,2017
 
Description Regular talks to public on impact of science on society and impact of society on scientific work 
Form Of Engagement Activity A talk or presentation
Part Of Official Scheme? Yes
Geographic Reach International
Primary Audience Public/other audiences
Results and Impact The talks have stimulated debate and discussion and instigated invitations to give further talks.

The talks gave rise to me developing novel university courses and to be invited to other universities to give talks on this subject ie scientific impact
Year(s) Of Engagement Activity 2009,2010,2011,2012,2013