A sol gel based needle type biosensor using 3-glycidoxypropyl dimethylethoxy silane, as silane agent was developed to improve the immobilisation efficiency of glucose oxidase (GOD). The glucose sensor was coated with 3C-copolymer as outmost layer to increase sensor's bioconipatibility. The biosensor's performance fabricated by this technique was compared with the conventional sensors which uses glntaraldehyde as the cross link agent for immobilisation of GOD. Reliable results were obtained from various characterisation tests, including sensor response to glucose, the sensitivity and stability tests. In the stability test, both types of the sensors were immersed in 20 mM glucose solution for more than 24 hours and the sol gel based sensor showed a better stability. This indicates that the sol gel immobilisation technique applied is able to retain ensyme for longer time of period compared to the conventional method. Furthermore, the studies revealed when the sensors were tested in a glucose solution containing 1 % bovine serum albumin in a long term stability test, the performance of the sol gel based sensor coated with 3C-copolymer was not affected considerably by protein adsorption, which is a vital character for an in vivo biosensor.
