The success of implantable device technologies, such as artiﬁcial joint, vascular graft, cardiopacemaker, cardiovascular, drug delivery system, and biosensor,
had improved the patients’ life quality. However, with the advances of these technologies, the view of biocompatibility had extended from the “the host tolerates the device” to “the device tolerates the host and vice versa”.1,2 For example, a subcutaneous glucose sensor comprises of immobilized enzymes, electrodes and a semi-permeable membrane. The semi-permeable membrane acts as a protecting layer that keeps the enzyme and electrodes from the attack of the immune system and it allows glucose from interstitial space to diffuse through. In order to be successful, the semi-permeable membrane must not induce pathogenic reactions to the host. On the other hand, the glucose permeability of the membrane must be maintained at all times. Hence, the problem of biofouling needs to be reduced as much as possible.