Help Desk: http://www.ucl.ac.uk/ras/portico/helpdesk
- UCL School of Pharmacy
- Faculty of Life Sciences
Dr Williams received a MChem (Hons) degree from the University of Oxford in 2002. He remained in Oxford working with Prof Dermot O’Hare for a DPhil (PhD) in materials chemistry, which was completed in 2005. Gareth then spent three years working in science programme management for the UK government, before returning to Oxford to take up a post-doctoral position in 2009. In September 2010 he joined London Metropolitan University as a Senior Lecturer in Pharmaceutical Science, and in November 2012 was appointed to the UCL School of Pharmacy as a Lecturer in Pharmaceutics. Gareth is a regular reviewer for a number of journals including Ind. Eng. Chem. Res., J. Solid State Chem., J. Mater. Chem., Cryst. Growth Des., and J. Phys. Chem., and is the Younger Members’ representative for the Royal Society of Chemistry Chiltern and Middlesex Section Trust Committee.
Inorganic drug delivery systems
A wide range of solid-state materials exists in which there is vacant space: it is often possible to fill this with a 'guest' species. We are using this chemistry to develop advanced materials with biomedical applications, for instance in drug or DNA delivery. Work is focussed on layered double hydroxides (LDHs) and hydroxy double salts (HDSs). These materials have positively charged layers, with charge-balancing anions located in the interlayer space (e.g. the LDH [LiAl2(OH)6]Cl.H2O or the HDS [Zn5(OH)8](NO3)2.H2O). A wide range of bioactive molecules can form anions and be incorporated into the interlayer region through replacement of the initial interlayer anion: these nanocomposites can be used to store and deliver drugs at a sustained rate. Such formulations can obviate the need to take frequent doses of medicines (making a patient's life easier) and help maintain drug levels at safe yet efficacious levels in the body. We are also interested in HDSs and LDHs for the separation of isomers of pharmaceutical agents. Often, we find they take up one isomer with a very high degree of preference. This offers a cheap and facile route to the separation of isomeric forms of a drug, ensuring efficacy and ameliorating toxic effects.
Polymeric drug delivery systems
A second strand of work comprises the exploration of nanoscale fibres, consisting of a polymer filament with functional components (e.g. drug molecules) embedded, as pharmaceutics. Fibres can be easily synthesised by electrospinning, in which a solution containing a polymer and a functional component is sprayed from a syringe towards a target collector with a high voltage applied between the two. The resulting materials have significant potential in increasing the solubility of poorly water soluble drugs, and may be exploited to drive "bottom-up" self-assembly processes. We are investigating the use of these materials for sustained drug delivery and for the precise targeting of drug molecules.
Vaccination saves 3 million lives annually through the induction of protective immunity to infection. For safety reasons, modern vaccines tend to contain pathogen subunits to which adjuvants, such as aluminium oxy-hydroxide (AlOOH; alum), must be added to deliver immunity. Alum provokes strong antibody-mediated immunity against bacterial toxins, but cannot stimulate the cellular immune response required to eliminate virally infected cells or cancers. Working with collaborators in Oxford and Ghent we are developing alternative inorganic vaccine adjuvants to drive different and/or more powerful immune responses, and have recently patented significant developments in this area.
Working with Dr Simon Gaisford, efforts are currently underway to develop the technique of Rapid Heating X-ray Diffraction (RHXRD) at the Diamond Light Source. Using the new state-of-the-art facilities there and those developed by Prof Dermot O’Hare’s group in Oxford, we will record diffraction patterns while pharmaceutical materials are heated and cooled very rapidly (2000 °C / min). In combination with Dr Gaisford’s rapid heading differential scanning calorimetry work, these data will permit us to identify and characterize new polymorphs of pharmaceuticals, and to enhance understanding of the transitions between them.
I teach pharmaceutics aspects of a number of modules in the UCL MPharm course, and also the MSc courses offered by the UCL School of Pharmacy. I am also course director for the MSc in Drug Delivery.