A brief summary of different applications of scanning ion conductance microscopy (SICM) in topography imaging, ion channel event recording, mechanical stimulation, simultaneous ion current and electrochemical current recording, localized delivery, single cell sampling and transport studies. Configurations of nanopiettes for different applications are illustrated below.
High Resolution Topography
- Live samples
- Non-contact and non-invasive
- In electrolyte solution
- Easy fabrication of nanopipette
Applications
- Live cell / delicate materials morphology characterization in solution
- Long-term observation of cell growth
References
- Hansma et al. 1989 Sicence, Gorelik et al. 2003 PNAS, Shevchunk et al. 2006 Angew. Chem., Novak et al. 2009 Nat. Methods
Smart Patch-Clamp
- Same probe for scan and patch clamp
- Positioning pipette with high spatial resolution
- Work on non-transparent samples
- Higher patch success rate
Applications
- Study ion channels on samples difficult in conventional patch clamp
- Study ion channels on small membrane features (~100 nm)
References
- Gu et al. 2002 FASEB J., Bhargava et al. 2013 Cir Res, Novak et al. 2013 Neuron
Mechanical Stimulation
- Positive pressure on pipette
- Non-contact, minimum or no damage
- Stimulation is limited in a very small region
Applications
- Mapping mechanical sensitivity of cells.
References
- Sanchez et al. 2008 Biophys. J., Rheinlaender et al. 2013 Soft Matter
Localized Delivery
- Delivery materials (e.g. fluorescent probes) to a single cell/small region
- Fast delivery with minimum damage (to cells)
Applications
- Localized staining to facilitate optical imaging
- Nanowriting with controlled deposition through pipette
References
- Bruckbauer et al. 2007 Biophys. J., Piper et al. 2008 J. Am. Chem. Soc., Babakinedjad et al. 2013Anal. Chem.
Localized Sampling
- Obtain material for further analysis from a single cell
- Minimum damage to the cell (determined by nanopipette size)
Applications
- Nanobiopsy
- Single cell analysis
References
- Actis et al., 2014 ACS Nano
SICM-Scanning Electrochemical Microscopy (SECM) with a Ring Electrode
- Multifunctional probe with coating of conductive material and insulation outer layer
- Robust feedback with SICM to control probe-sample distance
- Ring shape SECM electrode measure local electrochemical property
Applications
- Correlation of local topography and electrochemical property in both life and material science
References
- Comstock et al. 2010 Anal. Chem., Takahashi et al. 2010 J. Am. Chem. Soc., Thakar et al. 2013 Analyst
SICM-SECM with Double Barrel Probe
- Carbon deposited in one barrel of the nanopipette
- Easy fabrication compared to the ring electrode
Applications
- Correlation of local topography and electrochemical property in both life and material science
References
- Pollard et al. 2012 MRS Proceedings, O’Connell et al. 2014 Anal. Chem.
Scanning Electrochemical Cell Microscopy (SECCM)
- Scan in air
- Current through the meniscus at the end of the two barrels
Applications
- Electrochemical mapping of materials
- Create multidimensional nanostructures of conducting polymers on conducting substrate
References
- Ebejer et al. 2010 Anal. Chem.,Snowden et al. 2010 Anal. Chem.
Potentiometric-Scanning Ion Conductance Microscopy (P-SICM)
- Using a double barrel pipette, one measures current for SICM distance control
- Another barrel measures potential at the tip of the pipette
- Higher signal-to-noise ratio for potential measure
Applications
- Localized conductance measurement in synthetic porous membrane and cell monolayers (e.g. paracellular transport of tight junctions in epithelial cells)
References
- Chen et al. 2013 Anal. Chem., Zhou et al. 2014 Langmuir