An investigation into the metal binding behaviour of silk using radiotracer probes

INTRODUCTION This study examined the binding behaviour of selected metal ions by degummed silk fibres and fine silk powders. The presence of metal ions is known to influence the formation of fibre structure during natural spinning of protein solution into fibres by silkworms and spiders[1,2] Therefore, understanding how metal ions interact with silk can ultimately provide important insight into ways of engineering ultra high strength spider like fibres from recombinant silk like proteins. The reversible and selective metal ion binding properties of silk has shown potential for application in areas such as recovery and or recycling of precious metal ions from environmental and industrial effluents[3]. Such binding behaviour is also expected to have use in the biomedical field in areas such as drug delivery and skin grafting where use of silk has been extensively studied in recent years[4].