A simple way would be to deposit enzyme solution on the surface of GCE and cover it by a membrane such as a dialysis membrane or cellulose acetate membrane. Alternatively you can make a membrane by casting it from a liquid i.e. a Nafion dispersed in a buffer solution or chitosan dissolved in diluted acetic acid. After the membrane is dried the enzyme should be trapped behind it without any leakage. We have a good experience especially with a chitosan membrane, which is highly biocompatible. I am sure you can find a lot of protocols based on deposition of chitosan membranes.
A simple way would be to deposit enzyme solution on the surface of GCE and cover it by a membrane such as a dialysis membrane or cellulose acetate membrane. Alternatively you can make a membrane by casting it from a liquid i.e. a Nafion dispersed in a buffer solution or chitosan dissolved in diluted acetic acid. After the membrane is dried the enzyme should be trapped behind it without any leakage. We have a good experience especially with a chitosan membrane, which is highly biocompatible. I am sure you can find a lot of protocols based on deposition of chitosan membranes.
I may suggest some method, which is covalent immobilization technique. prepare an manganese acid solution and soake your electrode into it. and wait for 2 hours and fullerene residues will be oxidized and COOH or OH groups will form(you can search it as glassycarbon activation). then you can do whatever you imagine to immobilize it, you can activate these groups by NHS/EDEC reactives or you can use a linker. I believe that this direct attachment of enzymes on electrode surface will become more beneficial.
I arrive a little late, but if you might have the possibility of fabricating electrospun membranes (which is really a simple set up) I suggest you using the method described in this paper "Nylon Nanofibrous Biosensors for Glucose Determination (Scampicchio et al., 2010)". I'm not really an expert, but I use this method with different enzymes on a daily basis and I find it really simple and effective. Regards
I guess there are umpteen ways to do it. But any pointers on why one is better than other or more importantly what are the factors that determine a "better" immobilizing method- cost, sensitivity, stability ? and i guess most important is repeatability :-)