3D-printed drug-eluting auxetic meshes for preventing biofilm formation and capsular contracture associated with breast implants

This is an exemplar PhD project co-supervised by Dr. Zafer Kazanci (School of Mechanical and Aerospace Engineering) and Prof. Karl Malcolm (School or Pharmacy). No funding has yet been secured for the project. We particularly welcome applications from students (including international students) who are willing and able to self-fund their PhD, UK/EU applicants for DfE studentship application, and Chinese applicants with a Masters degree for the China Scholarship Council (CSC)–QUB co-founded PhD studentship (to be launched in Jan/Feb 2024). 

Capsular contracture is a common complication associated with breast implants following reconstructive or aesthetic surgery in which a tight or constricting scar tissue capsule forms around the implant, often distorting the breast shape and resulting in chronic pain. Various surgical scaffold materials—including synthetic adsorbable polymeric meshes and biological meshes (also known as acellular dermal matrices)—are now routinely used in breast reconstruction/augmentation to help provide tissue support. While these meshes are not direct adaptions of the breast implants themselves, their placement around the implant is intended to increase biocompatibility, encourage rapid host revascularization and cell repopulation, and limit the extent of interactions between the silicone implant and the host tissues, thereby improving surgical outcomes. Use of non-biodegradavble polypropylene meshes impregnated with the antibiotics minocycline and rifampicin drastically reduced in vivo the appearance of grade III and IV capsular contracture, even when S epidermidis was inoculated next to the implants. Logan Ellis et al. [1] described the wrapping of silicone breast implants in drug-loaded polyurethane nets to provide sustained release of the glucocorticoid triamcinolone to prevent fibrosis. Thus, the incorporation of meshes and matrices around the breast implants is becoming an increasingly routine strategy to reduce the incidence of capsular contracture. 

Different approaches towards the development of more efficient materials have led to an interest in auxetic structures that exhibit a negative Poisson's ratio, meaning they expand in all directions when stretched and contract when compressed unlike other conventional materials. While auxetic structures have been studied and used in various applications, including engineering and biomedical fields, their application in breast implants is novel. 

The capacity of auxetics to form dome-like, synclastic surfaces when bent (characterized by a positive Gaussian curvature (K) at every point of the surface) shows that the use of auxetics as a breast implant has a great potential.  

The potential impact of using auxetic structures for breast implants could include: 

1. Improved Fit and Comfort: Auxetic materials may provide a better fit to the natural contours of the breast, adapting to movement and changes in body position. This could result in increased comfort for the wearer. 
2. Reduced Rupture Risk: Conventional breast implants are often filled with silicone gel or saline solution, which can rupture over time. Auxetic structures, being more adaptable and resilient, may reduce the risk of rupture or leakage. 
3. Natural-Looking Movement: Auxetic materials may mimic the natural movement of breast tissue more closely than traditional implants. This could result in a more natural appearance and feel. 
4. Customization and Personalization: Auxetic structures can be designed with specific mechanical properties, allowing for customization based on individual needs and preferences. This could lead to more personalized breast implants. 
5. Potential for Tissue Integration: Depending on the specific properties of the auxetic material, there might be a potential for better integration with surrounding tissues, reducing the risk of complications such as capsular contracture. 
6. Reduced Rippling: Auxetic structures may have the potential to reduce visible rippling or wrinkling of the implant, which is a common concern with traditional implants, especially in thin-skinned individuals. 

In this project, we will develop custom, 3D-printed, drug-eluting, auxetic, synthetic meshes from selected biodegradable (adsorbable) polymers, suitable for use as a breast implant mesh for reducing capsular contracture. 

We will consider UK/EU for DfE studentship, Chinese applicants with a Masters degree for the CSC (China Scholarship Council)-QUB co-funded studentship and worldwide applications for self-funded projects. 

Applicants should have a 1st or high 2.1 honours degree (or equivalent) in a relevant subject. Relevant subjects include Pharmacy, Pharmaceutical Sciences, Biochemistry, Biological/Biomedical Sciences, Chemistry, Engineering, Biomedical Engineering or a related discipline. Students who have a 2.2 honours degree and a Masters degree may also be considered, but the University reserves the right to shortlist for interview only those applicants who have demonstrated high academic attainment to date. 

Postgraduate Research applicants must have applied to Queen’s, via the Direct Applications Portal. 

https://dap.qub.ac.uk/portal/user/u_login.php  

Please note that applicants do not need to draft a detailed research proposal. Instead, applicants can simply copy and paste the summary descriptive text provided above. However, you may wish to elaborate further on the concept, particularly if you have other ideas around the general topic.  

As explained above, this project has not yet secured an external source of funding. Before making an application, students should therefore ensure they have identified a viable funding source to support their postgraduate studies. Self-funding international applicants are particularly encouraged to apply. 

Funded PhD studentships available in the School of Pharmacy, Queen's University Belfast 

http://www.qub.ac.uk/schools/SchoolofPharmacy/Research/PostgraduatePositions/  

Research at the School of Pharmacy, Queen's University Belfast 

http://www.qub.ac.uk/schools/SchoolofPharmacy/Research/ 

Dr. Zafer Kazanci’s research homepage 

https://pure.qub.ac.uk/en/persons/zafer-kazancı 

Prof. Karl Malcolm’s research homepage 

https://pure.qub.ac.uk/en/persons/karl-malcolm 

Dr. Peter Boyd’s research homepage 

https://pure.qub.ac.uk/en/persons/peter-boyd 

List of relevant publications (with links) 

[1] Biological and synthetic mesh use in breast reconstructive surgery: a literature review / https://doi.org/10.1186/s12957-016-0874-9 

[2] Evaluation of Antibiotic-Impregnated Mesh in Preventing the Recurrence of Capsular Contracture / https://doi.org/10.1093/asj/sjy171 

[3] Pharmacological Approaches for the Prevention of Breast Implant Capsular Contracture / https://doi.org/10.1016/j.jss.2022.06.073 

[4] Auxetic Structures for Tissue Engineering Scaffolds and Biomedical Devices / https://doi.org/10.3390/ma14226821