John Hardy
Pro-Active Dendrimers for Active-Ingredient Formulation

Project Overview

Pure active ingredients are of limited use to an end user and they are usually combined with other components (appropriate solvents/surfactants) to make them applicable. As a result of this, there is great industrial and academic interest in the formulation of active ingredients such as drugs and agrochemicals. Poor formulation results in inefficient dosage, hence the need to use excessive quantities of active ingredient, which is expensive and potentially harmful to the environment. There are many examples in the literature of different formulation systems, such as: the covalent incorporation of actives into bio/synthetic polymers; or the non-covalent physical incorporation of actives in aerosols, emulsions, gels or micro/nano-particles (capsules / spheres) (1-2).

In my first year I have focused on the synthesis of a small library of novel dendritic branches that modify the formulation properties of model active ingredients. The dendritic branching interacts with active ingredients through non-covalent supramolecular interactions at the core of the dendritic branches.

The library is based upon biocompatible L-lysine dendrimers that have been extensively developed in our research group (3-5 ). The surface of the dendrimers has been modified in order to alter the formulation properties of the actives in a pro-active manner, based upon previous research in our group. The anion binding and self assembly properties of these dendrimers are under investigation.

During my PhD I set up an international collaboration at University of Illinois - Urbana-Champaign. This involved me working in America for about 6 weeks. I also attended the Supramolecular chemistry Conference in Notre Dame (Indiana) in 2004. During my PhD I also presented a poster at the International Dendrimer Symposium in Berlin, Germany, and attended the follow up meeting in Michigan, USA.

1. E.R. Kenawy, D.C. Sherrington; Eur. Polym. J.; 1992, 28 (8), 841-862
2. Controlled Release Technologies: Method, Theory and Application, Vol. II. Ed. F. Kydonieus, CRC Press, Boca Ranton, 1980
3. G.M. Dykes, D.K. Smith, G.J. Seeley, Angew. Chem. Int. Ed., 2002, 41, 3254-3257.
4. K.S. Partridge, D.K. Smith, G.M. Dykes, P.T. McGrail, Chem. Commun., 2001, 319-320.
5. G.M. Dykes, L.J. Brierley, D.K. Smith, P.T. McGrail, Chem. Eur. J., 2001, 7, 4730-4739.

Photo of Reetta, Andrew and John at a summer house in Finland 2003