Patent ID: 8277713

Claim:
A method for forming a membrane for use with an implantable electrochemical glucose sensor, the method comprising: forming a membrane configured to provide in vivo an interface between an implantable electrochemical glucose sensor and a biological fluid, wherein forming the membrane comprises forming a domain configured to substantially reduce a flux of potentially electrochemically interfering substances through the membrane and control diffusion of glucose and oxygen through the membrane, wherein forming a domain comprises: forming a sufficiently diluted solvent solution comprising a solvent and a polymer blend of a silicone-containing polyurethane polymer and a hydrophilic polymer, wherein the sufficiently diluted solvent solution comprises a ratio of polymer blend to solvent of about 1 to 10 wt. % polymer blend to about 90 to 99 wt. % solvent; and applying the solvent solution to a surface at a speed sufficient to substantially avoid film thickness inhomogeneities due to evaporation of the sufficiently diluted solvent solution.