With this award, the Chemical Measurement and Imaging program of the Chemistry Division is funding Professor Lane Baker at Indiana University to develop chemical/biochemical sensors which consist of lipid bilayers and ion channels suspended at the tip of a glass capillary, called ion channel probes (or ICPs). The sensor will be combined with scanning ion conductance microscopy (SICM), a probe imaging platform, to enable spatial location of the sensor on the order of 50-100 nm. By incorporating ion channels with selective responses, sensors that respond to unique analytes will be developed. The positionable ICP will be tested on porous membranes and will enable measurement of small molecules and ions at subcellular scales and will enable new studies of cellular communication. As such, it is expected that the tools developed in this work that will have broad application in chemical biology. Students trained in this project will learn state-of-the-art fabrication, measurement and characterization protocols, providing them with high level technical skills for the current workforce upon their graduation. In addition, efforts will be made to improve chemistry faculty engagement in evidence-based teaching methods.
The proposed research will provide new routes to chemically selective imaging methods, even at single molecule levels, with scanning ion conductance microscopy. This overcomes a significant drawback of scanning ion conductance microscopy; namely, the lack of chemical information collected. The use of inherently selective and sensitive ion channels will impart chemical sensing abilities to scanning ion conductance microscopy. As described, ICP-SICM promises to increase the reliable operation, signal and time response of sniffer patches, which will, in turn, inform the biochemical process they are commonly used to study.
