ANNALS OF MICROSCOPY Vol 3, March 2003 9 Surface properties and microporosity of polyhydroxybutyrate under scanning electron microscopy Azehar AL.Raouf*, Rani Samudin*, Razip Samian**, Karima Akool*, Nizam Abdulla* (*) Hospital University science Malaysia,School of Dental science, kubang kerian. bazehar@hotmail.com or azehar@kb.usm.my (**) University science Malaysia,Pinang,School of biology. ABSTRACT The objective of this study is designed to investigate the surface properties especially surface porosity of polyhydroxybutyrate (PHB) using scanning electron microscopy . PHB is thermoplastic polymer .The polymer is found in a variety of bacteria such as bacillus megaterium,bacillus cereus. PHB is located as granules in the cytoplasm of the bacterium. The PHB is a polyester which is used as implant material .PHB was produced locally by the biological plastic group in USM Penang and they supplied as the polyhydroxybutyrate (PHB) as granules. And Sterilization have been done by gamma radiation (25kg). SEM analysis were conduct ed at the Electron microscopy Unit using a Leica Cambridge S360at 10KV.PHB granules were sprinkled on the double-sided sticky tape attached on a SEM aluminium stub and sputtered with gold(10nm thickness) in a Polaron SC515 Coater, following which the samples were placed into the SEM specimen chamber for Viewing and recording.Scanning electron micrographs with different magnification of PHB surface revealed multiple pores with different sizes. Some pores reached to 20 μm in size and was found in the depth of the granules.The Results of this study showed that PHB has good surface porosity which is an important characteristic to the implant material to be a sa bone substitute. KEYWORDS: PHB, Scanning electron microscope, Pores INTRODUCTION PHB is a thermoplastic polyester with biodegradable and biocompatible properties, which has been extracted in large quantities from bacteria.PHB was first isolated from bacteria by 1926 by Lemogne subsequently, the polymer was found in a variety of bacteria such as bacillus megaterium, Rhodo spirillium rubrum and bacillus cereus, located as granules in the cytoplasm of the bacterium. If the bacteria are starved of an important nutrient for procreation,(sodium or phosphate), but have plentiful supply of carbon. Some worker found that PHB inclusions can accumulate to as much as 80% of the dry weight when bacterium is grown in media containing excess carbon.The most important features of PHB are the (up to 120°C resistance to high temperature. PHB polymer has high molecular weight,crystalline, brittle and not soluble in water. Important properties in this regard include porosity for cell in growth, pores are very important for the cells to enter and grow as well as capillary section of tissue fluid and blood. They also provide very large surface area for the invading cells or for interaction with cell. It has been suggested that PHB-based materials (copolymer and composites) could be suitable for medical applications. and this PHB polymer resorbablity obviates the need of a second surgical procedure for removal, which is actually the most important asset of the biodegradable implants. It has been used for the fabrication of temporary stents, bone plates, nails and screws. The present paper designed to study the surface properties of PHB under SEM. Back to Contents