Enzyme-electrode sensor with organosilane treated membrane

A sensor of the enzyme-electrode type, comprising:

• a sensor;
• and
• a membrane thereon which is permeable to liquids and solutes,
• wherein the membrane comprises a first layer of a polymeric material selected from the group comprising polymethyl methacrylate, polyurethane, cellulose acetate and other polymeric materials restricting the passage of electroactive interfering compounds,
• an enzyme-containing layer disposed on that side of the first layer which is remote from the sensor, and a second layer of polymeric material disposed on that side of the enzyme-containing layer which is remote from the first layer, said second layer being of a polymeric material selected from the group comprising polycarbonates and modified cellulose, said second layer of a type which has been treated by being exposed to contact with an organosilane having at least one halogen-containing group.

A method for determining an analyte in a specimen, said method including the steps of contacting said specimen with the outermost layer of a membrane of an enzyme-electrode type sensor, and measuring the response of said sensor to species that are formed from said analyte by said enzyme,

• wherein the improvement comprises said membrane that is permeable to liquids and solutes and which includes
• (i) a first layer of polymeric material forming that face of the membrane which is nearest said sensor;
• (ii) a layer containing said enzyme;
• and
• (iii) at least one second layer of polymeric material, at least one of said at least one second layers having been exposed to contact with a medium containing an organosilane, wherein at least one of said organosilane contacted layers lies between said enzyme-containing layer and said specimen.