School of Pharmacy and Biomedical Sciences
Biomaterials and Drug Delivery
The Biomaterials and Drug Delivery (BADD) research group produces cutting-edge fundamental science, which it then translates into industrially relevant products and processes.
The primary aim of the group is to investigate biomaterials for their potential use as drug carriers, bioadhesives, therapeutic (and diagnostic) agents, and surgical implants. The work on mucoadhesion has led to a number of industrially held patents and the non-stick biomaterials work has been publicised extensively by the national press on both sides of the Atlantic.
Our Current Research
Controlled and targeted drug delivery
- Design and development of specific retentive delivery systems aimed at mucosal surfaces (eye, mouth and gastrointestinal tract).
- Enhancement of percutaneous absorption by chemical modification of therapeutic agents; development of quantitative structure-permeability models and prodrug strategies for percutaneous absorption.
- Intracellular delivery and gene therapy - development of synthetic polymer-DNA conjugates that are designed to cross cellular barriers and respond to external stimuli enabling release of therapeutic genes into the nucleus.
- Low-surface-energy materials.
- Synthesis, surface characterisation and various applications of polymeric materials with ultra-low-surface-energy characteristics.
Bioadhesion and mucoadhesion
- Synthesis, characterisation and evaluation of bioadhesive materials for therapeutic use in the eye, mouth, stomach, colon, nose and vagina.
- Molecular imprinting.
- Synthesis of imprinted polymers and regioselective organic synthesis at imprinted polymer binding sites.
- Synthesis and characterisation of new polymerizable receptor molecules with potential applications as either binding agents or controlled release systems.
- Support matrices for in vitro toxicology.
- Novel therapeutic agents for targeting cancer tumours.
- Development of materials that inhibit bacterial binding to biological surfaces and biomaterials.
- Use of responsive ('smart') polymers displaying hydrophilic-hydrophobic transitions as a potential means of controlling cell adhesion.
- The use of contact angle goniometry, atomic force microscopy, X-ray photoelectron spectroscopy, infrared spectroscopy and other analytical techniques as means of quantifying surface heterogeneity in Biomedical Materials.
Long-term Molecular Dynamics Simulations of Bioactive Peptides
To elucidate the principles of bioactivity by means of ligand-receptor interactions, it is important to understand the dynamical nature of ligands and receptors even in the unbound state. As a contribution to this understanding, we are studying the molecular dynamics of small peptide-hormones (e.g. Oxytocin and Vasopressin) via Amber forcefield simulations with explicit water solvation, over timescales of several microseconds. The conformational space is analysed, inter alia, with DASH. Possible reaction paths and free energy barriers for conformation-interconversion are calculated using umbrella sampling. This project is carried out in cooperation with the Peptide Research Network of Excellence (PeReNE) as part of the INTERREG IV A France (Channel) England Programme.
The Clinical Pharmaceutics Group led by Dr Marisa van der Merwe, in collaboration with Dr Karen Ball, is investigating the chemical and physical compatibility of continuous intravenous drug infusion combinations used in paediatric intensive care. Existing data usually relate to no more than two drugs under specific conditions, and most data relate to physical compatibility only (precipitation or colour change) and more complex analyses using analytical techniques such as high performance liquid chromatography (HPLC-see image) are uncommon. The group uses HPLC to investigate the chemical and physical compatibility of more than two, and up to five, prescribed drugs that may be mixed if there is limited intravenous access. Research also investigates the optimum device for the nebulisation of IV drugs, including antibiotic, mucolytic and anti-inflammatory drugs, used in the treatment of cystic fibrosis lung disease. Different types of nebuliser produce different particle sizes and the ability of a nebuliser to deliver therapeutic concentrations in the lungs depends on the physical characteristics of the solution being nebulised. In collaboration with Professor Janis Shute, the group are investigating the mucolytic and anti-inflammatory effect of enoxaparin compared to unfractionated heparin, and the particle size and delivery of solutions nebulised from jet nebulisers and the new generation of vibrating mesh nebuliser.