Electrochemical Analysis of Ion Channels and Transporters in Pore-Suspending Membranes - Applications of Electrochemistry and Nanotechnology in Biology and Medicine - page 326

are, in general, more sensitive to permeabilising agents as they
lack remaining organic solvent (see Fig. 12 ). A similar influence
of solvent was observed for SSMs with adsorbed PM-fragments.
While the photocurrent signal obtained from SSMs prepared in the
presence of organic solvent was not influenced by CCCP up to a
concentration of 20 μM, the current signal gained from solvent-
free SSMs indicated that an electrically permeable layer is formed.
VI. CONCLUDING REMARKS
We have developed two different methods to prepare pore-
suspending membranes, which both exhibit a high long-term sta-
bility, while they are accessible from both aqueous sides. While
nano-BLMs allow for ion channel recordings on the single channel
level, pore-suspending membranes obtained from fusing unilamel-
lar vesicles on a functionalized porous alumina substrate enable us
to generate membranes with high protein content. However, these
membranes exhibit a considerably lower membrane resistance
compared to nano-BLMs. In summary, pore-suspending mem-
branes are available that might pave the way for chip-based tech-
nologies, giving access to functional assays for ion channels and
transporter proteins.
ACKNOWLEDGMENTS
We like to thank the DFG and BMBF for financial support. E.K.
Schmitt thanks the Fonds der Chemischen Industrie for a PhD fel-
lowship.
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