Professor of Advanced Drug Delivery, University College Dublin
The Use of Nanoparticles with Excipients to Enable Oral Peptide Delivery: Tales from the EU FP7 TRANS-INT Consortium
TRANS-INT (2012-2017) was a consortium of 19 groups across the EU with the goal of advancing knowledge around how nanoparticles entrapped with peptides can negotiate the intestinal barrier. The work from this group regarding several nanoparticle prototypes using insulin as a model is starting to be published and, in addition, we were a reference centre for rat jejunal loop instillation studies to examine delivery of most consortium prototypes. One prototype was a silica-based nanoparticles: a reproducible synthesis of a lyophilised product was established with extensive physicochemical characterisation by up to ten techniques. It released insulin in simulated small intestinal- but not gastric fluid. It delivered insulin in the rat model, but the key was that co-entrapped excipients behaved as permeation enhancers for released peptide. The nanoparticle benefit was to protect insulin and to release it at the epithelium in high concentration along with excipients. We confirmed this model with a second prototype, a polyelectrolyte complex of chitosan, hyaluronic acid and insulin. This nanocomplex only delivered insulin across rat jejunal loops when the enhancer, sucrose laurate, was included. These and most other prototypes in the consortium (constructed without active targeting with surface ligands) typically remained in the GI tract associated with mucus or with the epithelium, as determined by fluorescence imaging.
David Brayden is Full Professor of Advanced Drug Delivery at the UCD School of Veterinary Medicine and a Principal Investigator at the Conway Institute at UCD. He is also Adjunct Professor at NUI Galway. Following a Ph.D. in Pharmacology at the University of Cambridge, UK, and a post-doctoral research fellowship at Stanford University, he set up Elan Corporation's pharmacology laboratory in Dublin in 1991. At Elan, he became a senior scientist. In 2001, he joined UCD as lecturer in veterinary pharmacology and was promoted to Full Professor in 2014. Professor Brayden is a co- lead PI on an SFI Strategic Research Centre (CURAM)) that was awarded 30 million euro by SFI in 2014 and was the Deputy Coordinator of an FP7 grant on oral nanomedicines (2012-2017)). His research team was awarded the Best Research Paper Prize of the Journal of Veterinary Pharmacology and Therapeutics (2005). At UCD, he was Chairman of the Animal Research Ethics Committee (2005-2007) and serves on the main UCD Research Ethics Committee as well as on the President's Research Strategy Board. On the teaching side, he coordinates undergraduate modules on Biological Fluids and Drug Development and contributes to modules on Cell Communication and to Thematic 4th Level programmes on drug delivery and also leads Drug Discovery and Development modules for Pharmacology students. He works as an independent consultant for drug delivery companies.