3D printing of drug delivery implants

Additive manufacturing (AM) encompasses a wide range of processes that create structures through deposition or binding of materials in successive layers to produce a 3D object. Our research group are experts in conventional thermoplastic processing, and particularly injection molding to produce drug delivery devices. We are uniquely placed in our use of Arburg Plastic Freeforming (APF), a thermoplastic, high pressure, droplet deposition printer. It is similar technology to an injection molding machine and works with pelletised granulate material giving us the capability to work with very flexible or highly brittle polymers. Properties including geometry, density and surface area of devices can be manipulated in ways that would be impossible using conventional thermoplastic processing techniques.

Polycaprolactone (PCL) scaffolds have suitable mechanical and bioresorbable characteristics for long-term bone implantation. Various 3D porous PCL scaffolds containing the bone-repairing biomaterial hydroxyapatite (HA) have shown promise to treat challenging orthopedic injuries such as critical-sized defects and non-union fractures. The presence of HA enhances cell adhesion, proliferation and osteogenic differentiation and recent studies have incorporated other elements or modified the HA to further potentiate the effects.

This project aims to incorporate HA or related actives into dual density PCL scaffolds by additive manufacture (AM) using Arburg® Plastic Freeforming (APF). As part of this study, 3D scanning techniques will also be utilised to understand the feasibility of producing repair scaffolds that can be tailored to individual patient’s injuries.

The project will provide extensive training and skills development for the student in the following topics:

· Thermoplastic compounding, additive manufacturing Bone repair technology

· 3D scanning and Computer Aided Design

· Preparation and characterisation of active-eluting scaffolds

· HA quantification using suitable analytical methods

· In vitro release testing

· Use of thermal analysis methods

· Rheological and mechanical testing methods

· Planning and organising skills: designing and planning of experiments

· Numeracy and statistical skills

There is considerable clinical interest in developing next generation, bone repair implants. As part of this project, the successful student will acquire unique insights to help progress this new technology.

Home applicants must meet the following academic criteria:

1st or 2.1 honours degree in a relevant subject. Relevant subjects include Pharmacy, Pharmaceutical Sciences, Biochemistry, Biological/Biomedical Sciences, Chemistry, Engineering, or a closely related discipline.

International applicants must meet the following academic criteria:

IELTS (or equivalent) of 7.0, a 2.1 honours degree (or equivalent) and a master’s degree in a relevant subject.

Applicants should apply through the University's Direct Application Portal: https://dap.qub.ac.uk/portal/user/u_login.php