Tightly Sealed 3D Lipid Structure Monolithically Generated on Transparent SU-8 Microwell Arrays for Biosensor Applications

Artificial lipid membranes are excellent candidates for a new biosensing platforms because their structures are similar to cell membranes and it is relatively easy to modify the composition of the membrane. The freestanding structure is preferable for this purpose since more manageable reconstitution of membrane protein. Therefore, most of the lipid membranes for biosensing are based on 2-dimensional structures that are fixed on a solid substrate (unlike floating liposomes) even though they have some disadvantages, such as low stability, small surface area, and potential retention of solvent in the membrane. In this paper, 3-dimensional freestanding lipid bilayer (3D FLB) arrays were fabricated uniformly on SU-8 microwells without any toxic solvent. The 3D FLBs have better stability and larger surface area due to their cell-like structure. In order to improve sealing characteristics of the 3D FLBs, the applied frequency of AC field was controlled during the electroformation. The 3D FLBs were observed thro...