Microscope: Scanning Probe - AFM, Bioscope

Contact-mode AFM image of hematite pyramids grown under acidic dissolution conditions on the (001) surface of natural hematite

EMSL's Digital Instruments BioScope™ Atomic Force Microscope (AFM) combines optical and AFM techniques used to examine heterophase processes on mineral surfaces and to image biological systems, such as bacterial colonies, on minerals and other substrates.

The BioScope AFM allows samples to be examined in fluids or air with little or no sample preparation. Its optics provide an effective magnification range of 25 to 10,000,000 times and can be used simultaneously with bright-field, fluorescence, and confocal techniques. The microscope supports all major AFM-imaging techniques and modes, including contact and intermittent contact (TappingMode™) atomic force, lateral force, force modulation, phase, lift, etc. The system's NanoScope IV controller enables high-speed data capture of high-pixel-density images (up to 4096 data points per scan line) that makes possible characterization of surface interactions at timescales previously inaccessible to the scanning probe microscope. The controller enables simultaneous acquisition through up to four independent data acquisition channels. A full range of data acquisition and analysis algorithms is included in the upgraded control software.

The entire microscope is housed in an acoustic isolation box mounted on an air table. Additionally, an in-house designed glove box chamber allows for sample preparation and AFM work to be performed under atmospheric control. Various electrical and fluid feed-throughs are ported on the glove box, and motorized programmable microliter pumps are available to provide batch or mixed-flow, low noise, and simultaneous push-and-pull fluid flow circuit. In addition, EMSL researchers designed an environmental chamber and fluid cell specifically for use with this instrument. The overhead scanner and optical scope design makes sample accessibility, alignment, and manipulation in fluid convenient and quick.

All Related Publications Related Publications

1. Bioreduction of hematite nanoparticles by the dissimilatory iron reducing bacterium Shewanella oneidensis MR-1.
2. Long-Range Electron Transfer Across Cytochrome-Hematite (a-Fe2O3) Interfaces.
3. Antibody recognition force microscopy shows that outer membrane cytochromes OmcA and MtrC are expressed on the exterior surface of Shewanella oneidensis MR-1.
4. Origin of two time-scale regimes in potentiometric titration of metal oxides. A replica kinetic Monte Carlo study.
5. Role of Directed van der Waals Bonded Interactions in the Determination of the Structures of Molecular Arsenate Solids.