Fabrication of antibacterial nanopatterned coatings inspired by wings of insects

Bacterial fouling is a pervasive process responsible for catastrophic failure and fatal health issues in industrial and biomedical settings. To minimize the medical and environmental risks associated with biochemical treatments of bacterial fouling, this project investigates the potential of an alternative physical approach mimicking natural antibacterial materials. Seeking inspiration for antibacterial materials in natural species, insects stand out as impressive examples; supreme antifouling functionalities are often found in wings of flying species of insects. The surface of insect wings is decorated with biodegradable chemicals that manifest long lasting self-cleaning and antifouling effects. These desirable qualities are believed to arise from the intricate nanoscale self-assemblies of waxes on the epicuticular surface of the wings. Such materials can potentially resist deposition/adhesion of bacteria (antifouling) and/or cause death through mechanical interactions with the cells (bactericidal effect), however, the exact antibacterial mechanism of insect wings and its effectiveness under relevant dynamic conditions remain ambiguous. This multidisciplinary project aims to resolve the physico-chemical properties of naturally available functional nanomaterials to derive inspiration for the efficient design and scalable fabrication anti-biofouling coatings. In particular, morphological and chemical properties of different species dragonflies, damselflies and cicada will be examined. Additionally, their performance under the impact of isolated droplets and continuous flow of pure and contaminated fluids will be investigated experimentally. Following the characterisation of natural examples, the project will develop new fabrication methods to achieve engineered counterparts. To achieve a sustainable and scalable nanofabrication method, this project will use crystallisation as a tool to manufacture biomimetic nanopatterned surfaces using waxes that are directly extracted from natural antifouling materials. Findings of the project will not only enrich our limited understanding of such complex natural systems, but also advance the design and fabrication approaches for new generations of functional materials.

<p>Nature generously offers access to a rich collection of multi-functional micro- and nano- biomaterials that we have only began to observe, apprehend, and reproduce in the past decades. Among all, insect wings, decorated with intricate networks of nanoscale structures, are flawless models of superhydrophobic, low-friction and antifouling surfaces that could prove beneficial in a variety of engineering and biomedical applications. This is an interdisciplinary PhD project set at the interface of biology, fluid mechanics, nanomaterials and microbiology seeking correlations between nanoscale patterns on the wings of various species of insects and their antibacterial performance in the vicinity of contaminated fluid environments. The main aims of the research are to (1) explore functionality of natural model surfaces observed in insect wings and (2) investigate the effectiveness of fluid-based manufacturing techniques for biomimetic fabrication of their engineering counterparts.</p> <p>Experimental investigations in the first phase of the project will involve: surface nanostructure and wetting characterisation, and frictional and fouling analysis. Analysis of antifouling functionalities will investigate effectiveness of the surfaces exposed to flows of nano- and micro-scale colloidal solutions, such as natural/synthetic polymer and colloidal solutions, to mimic fouling process observed in industrial and biomedical applications. Second phase of the project will be focused on the development of a fluid-based fabrication technique, based on crystallisation. With the goal to develop a sustainable nano-fabrication approach, in terms of material and process, effectiveness of crystallisation in thin film solutions of natural waxes will be explored to achieve spontaneous formation of nanopatterned materials at low energy/material cost over large surface areas. A range of analytical techniques will be employed for characterisation of natural and biomimetic surfaces: cross-polarised and scanning electron microscopy, atomic force microscopy, surface profilometry and X-ray diffraction crystallography will be used to analyse surface nano-topographies and chemical structures. Static and dynamic contact angle measurements will provide wetting characterisation. Lubrication/flow friction analyses will be performed side-by-side antifouling investigations, using tribological and microfluidics experimental platforms. Findings of this interdisciplinary project will upgrade our understanding of natural functional surfaces and promote development of smart energy-efficient manufacturing techniques for healthcare and engineering applications.</p>

<p>Formal applications for research degree study should be made online through the&nbsp;<a href="https://www.leeds.ac.uk/research-applying/doc/applying-research-degrees">University&#39;s website</a>. Please state clearly in the Planned Course of Study section that you are applying for<em><strong> PHD Mechanical Engineering FT</strong></em> and in the research information section&nbsp;that the research degree you wish to be considered for is <em><strong>Fabrication of antibacterial nanopatterned coatings inspired by wings of insects</strong></em> as well as&nbsp;<a href="https://eps.leeds.ac.uk/mechanical-engineering/staff/8170/dr-sepideh-khodaparast">Dr Sepideh Khodaparast </a>as your proposed supervisor.&nbsp; Please state in the Finance section <em><strong>the funding source you are applying for, if you are self-funding your PhD study or if you are externally sponsored (please include the name of your sponsor).</strong></em></p> <p>If English is not your first language, you must provide evidence that you meet the University&#39;s minimum English language requirements (below).</p> <p><em>As an international research-intensive university, we welcome students from all walks of life and from across the world. We foster an inclusive environment where all can flourish and prosper, and we are proud of our strong commitment to student education. Across all Faculties we are dedicated to diversifying our community and we welcome the unique contributions that individuals can bring, and particularly encourage applications from, but not limited to Black, Asian, people who belong to a minority ethnic community, people who identify as LGBT+ and people with disabilities. Applicants will always be selected based on merit and ability.</em></p> <p class="MsoNoSpacing">Applications will be considered on an ongoing basis. &nbsp;Potential applicants are strongly encouraged to contact the supervisors for an informal discussion before making a formal application. &nbsp;We also advise that you apply at the earliest opportunity as the application and selection process may close early, should we receive a sufficient number of applications or that a suitable candidate is appointed.</p> <p>Please note that you must provide the following documents in support of your application by the closing date of 3 April 2024 for Leeds Opportunity Research Scholarship or&nbsp;8 April 2024 for Leeds Doctoral Scholarship:</p> <ul> <li>Full Transcripts of all degree study or if in final year of study, full transcripts to date</li> <li>Personal Statement outlining your interest in the project</li> <li>CV</li> </ul>

Applicants to research degree programmes should normally have at least a first class or an upper second class British Bachelors Honours degree (or equivalent) in an appropriate discipline. The criteria for entry for some research degrees may be higher, for example, several faculties, also require a Masters degree. Applicants are advised to check with the relevant School prior to making an application. Applicants who are uncertain about the requirements for a particular research degree are advised to contact the School or Graduate School prior to making an application.

The minimum English language entry requirement for research postgraduate research study is an IELTS of 6.0 overall with at least 5.5 in each component (reading, writing, listening and speaking) or equivalent. The test must be dated within two years of the start date of the course in order to be valid. Some schools and faculties have a higher requirement.

<p style="margin-bottom:12px"><strong>Self-Funded or externally sponsored students are welcome to apply.</strong></p> <p><strong>UK</strong>&nbsp;&ndash;&nbsp;The&nbsp;<a href="https://phd.leeds.ac.uk/funding/209-leeds-doctoral-scholarships-2022">Leeds Doctoral Scholarships</a> (<strong>please note that the closing date is 8 April 2024 at 17:00 UK Time</strong>) and <a href="https://phd.leeds.ac.uk/funding/234-leeds-opportunity-research-scholarship-2022">Leeds Opportunity Research Scholarship</a> (<strong>please note that the closing date is 3 April 2024 at 17:00 UK Time</strong>) are available to UK applicants (<strong>please note that the closing date is 8 April 2024 at 17:00 UK Time</strong>). <a href="https://phd.leeds.ac.uk/funding/60-alumni-bursary">Alumni Bursary</a> is available to graduates of the University of Leeds.</p> <p><strong>Non-UK</strong> &ndash;The&nbsp;<a href="https://phd.leeds.ac.uk/funding/48-china-scholarship-council-university-of-leeds-scholarships-2021">China Scholarship Council - University of Leeds Scholarship</a>&nbsp;is available to nationals of China (now closed for 2024/25 entry). The&nbsp;<a href="https://phd.leeds.ac.uk/funding/73-leeds-marshall-scholarship">Leeds Marshall Scholarship</a>&nbsp;is available to support US citizens. <a href="https://phd.leeds.ac.uk/funding/60-alumni-bursary">Alumni Bursary</a> is available to graduates of the University of Leeds.</p> <p><strong>Important:&nbsp;</strong> Any costs associated with your arrival at the University of Leeds to start your PhD including flights, immigration health surcharge/medical insurance and Visa costs are <em><strong>not</strong></em> covered under this studentship.</p> <p>Please refer to the <a href="https://www.ukcisa.org.uk/">UKCISA</a> website for information regarding Fee Status for Non-UK Nationals.</p>

<p>For further information about this project, please contact Dr Sepideh Khodaparast by email to&nbsp;<a href="mailto:S.Khodaparast@leeds.ac.uk">S.Khodaparast@leeds.ac.uk</a></p> <p>For further information about your application, please contact Doctoral College Admissions by email to&nbsp;<a href="mailto:phd@engineering.leeds.ac.uk">phd@engineering.leeds.ac.uk</a></p>