Abstract
This thesis describes initially the development of novel MeV ion micro-beam techniques. It then discusses their application to the measurement of the diffusion of small molecules in polymeric and biological matrices which hitherto were not possible. The matrices studied were skin tissue, human hair, polymeric cable insulation and hydrophilic polymers. The important novel aspects of the techniques are: Use of 3He scanning ion microbeam. Use of dual uncollimated charged particle detectors to measure induced nuclear reaction products. Use of a very thin window detector capable of detecting X-rays from elements heavier than beryllium. Fast freezing of samples with liquid nitrogen to freeze diffusion profiles and eliminate sample deformation. Use of a liquid nitrogen cooled target stage to both retain water and effectively eliminate beam heating effects when exposing samples to vacuum and the ion microbeam respectively.