Solid-supported membrane biosensors

A solid-supported membrane biosensor, consisting of a solid A as a support, a lipid bilayer B as a membrane with spacers C incorporated between A and B and a receptor D embedded in the lipid bilayer, where

• a) A on the surface facing D consists of a corrosion-resistant material which allows sensing of an electrical signal,
• b) the lower lipid monolayer of B consists to 1-40% of all lipid molecules of di-(C.sub.8 -C.sub.30 -acyl)-phosphatidyl compounds with a naturally occurring head group and to 60-99% of a di-(C.sub.8 -.sub.30 -acyl)-phosphatide which, however, carries the spacer C instead of the head group, and whose upper lipid monolayer consists to 100% of di-(C.sub.8 -C.sub.30 -acyl)-phosphatidyl compounds with a naturally occurring head group, all acyl groups of a layer essentially being of equal length, but the acyl groups of the lower lipid monolayer being of equal or different length to those of the upper lipid monolayer,
• c) C consists of 1 molecule of ethanolamine which forms an ester bond to the phosphate group of B, an oligopeptide in helical or pleated sheet structure formed from 4-20 C.sub.2 -C.sub.10 -.alpha.-amino acids and a reactive group which enters into a chemical or physicochemical bond with A, all C of the biosensor being identical, and
• d) D has no contact with A.