Smart Controlled Release of Small Molecules

There is a growing need to devise methods for stabilisation of active ingredients in liquid and control of their release to the right place at right time, covering a wide range of industrial applications, particularly in the area of small sized molecules. Examples include controlled release of perfumes from fabrics or cosmetic products, delivery of artificial diets to marine fish larvae, bacteriacides in food pipelines, insecticides on soft furnishings or foliage, dyes or inks, adhesives, and drugs in the body. The best way to achieve these objectives is using microcapsules. However, controlling the stability and release of the core chemicals have been proven to be not well understood. In particular, controlling leakage of small molecules is extremely challenging and has not been achieved so far, which has limited the impact and suitability of microcapsules for wide applications. It is proposed to prepare microcapsules having dual shells, which combines the concepts of triggered release (the outer shell may be broken by applied mechanical force) and sustained release (the inner shell with certain permeability). The aim of this project is to formulate and characterise novel double-shell microcapsules with desirable structure and mechanical properties in order to realise stabilisation and controlled delivery of active ingredients made of small molecules, via collaboration between chemical engineering (Professor Z Zhang's group) and chemistry (Professor J Preece and Professor B Vincent, Polymer and Colloid Group in the University Bristol), and between the academic groups and two international companies Appleton Paper Inc., USA, which has three manufacture sites in the UK as a manufacturer of industrial microcapsules and Procter and Gamble, UK (Professor D. York's Technology Breakthrough Group) as an end user of microcapsules.