title: Potentiometric-scanning ion conductance microscopy for measurement at tight junctions.
abstract: Scanning Ion Conductance Microscopy (SICM) has been developed originally for high-resolution imaging of topographic features. Recently, we have described a hybrid voltage scanning mode of SICM, termed Potentiometric-SICM (P-SICM) for recording transmembrane ionic conductance at specific nanostructures of synthetic and biological interfaces. With this technique, paracellular conductance through tight junctions - a subcellular structure that has been difficult to interrogate previously - has been realized. P-SICM utilizes a dual-barrel pipet to differentiate paracellular from transcellular transport processes with nanoscale spatial resolution. The unique combination of voltage scanning and topographic imaging enables P-SICM to capture paracellular conductance within a nominal radius of several hundred nanometers. This review summarizes recent advances in paracellular conductance recording with an emphasis on the P-SICM based approach, which is applied to detect claudin-2 mediated permeability changes at the tight junction.
authors.affiliation: Department of Chemistry; Indiana University; Bloomington, IN USA.
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.affiliation: Department of Chemistry; Indiana University; Bloomington, IN USA.
authors.forename: Chiao-Chen
authors.initials: CC
authors.lastname: Chen
authors.affiliation: Department of Chemistry; Indiana University; Bloomington, IN USA.
authors.forename: Anna E
authors.initials: AE
authors.lastname: Weber
authors.affiliation: Department of Chemistry; Indiana University; Bloomington, IN USA.
authors.forename: Lushan
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Chemistry; Indiana University; Bloomington, IN USA.
authors.forename: Lane A
authors.initials: LA
authors.lastname: Baker
authors.affiliation: Renal Division; Washington University Medical School; St. Louis, MO USA ; Center for Investigation of Membrane Excitability Diseases; Washington University Medical School; St. Louis, MO USA.
authors.forename: Jianghui
authors.initials: J
authors.lastname: Hou
keywords: SICM; claudin; epithelium; ion channel; patch clamp; tight junction