LS AFM

Available with AFMWorkshop inverted microscope	Turnkey system with guaranteed results
Glass slides and petri dish sample holder	No additional sample holding options required for most applications
Includes liquid scanner	Readily scan samples in ambient air and liquids
Closed loop XY scanner	Zoom to feature with accurate positioning for F/D curves
LabVIEW software with USB communication	Readily adaptable to new operating systems
Probe exchange tool included	Reduce time for probe exchange (& use any manufacturer's probes)
Includes top view video microscope	Facilitates tip approach and laser alignment
Includes vibrating, non-vibrating, phase, LFM, and advanced F/D	Most common scanning modes included for life sciences applications
Pricing	From $58,945.00
Download:	LS AFM Product Datasheet PDF 3-D model of LS AFM Measuring and Understanding Force-Distance Curves

The LS AFM is used in biology applications in conjunction with an inverted optical microscope. Customers can buy the LS AFM in two variations:

LS AFM-A

For customers who already own an inverted optical microscope: In this configuration, AFMWorkshop fabricates a special plate that pairs the LS AFM with the customer's existing inverted optical microscope.

LS AFM-B

This configuration of the LS AFM includes a fully-featured inverted optical microscope.

Features of the LS AFM include:

• Dry and Liquid Z Scanner
• AFM Adapter Plate for Inverted Microscopes
• Linearized XY Scanner
• Advanced Force Distance Curves
• Glass Slide and Petri Dish Sample Holder
• Precision AFM Alignment System with Lock-Down
• Included Modes: Vibrating, Non-Vibrating, Phase and LFM
• Direct Drive Z Motor
• Compatible With Standard AFM probes
• Intuitive LabVIEW™ Software Interface
• High Resolution Zoom Video Camera
• High Resolution 24 Bit Scanning
• USB EBox Interface
• Available With AFMWorkshop's Inverted Optical Microscope (or Without)

The AFM Stage is secured on an adapter plate that is attached to the inverted optical microscope. There is an XY translation stage for moving the sample under the AFM Probe. Additionally there is an XY translation stage for moving the AFM over the inverted optical microscope axis.

Sample Stage for the LS AFM

Inverted Microscope (LS AFM-B Only)

The LS AFM may be purchased as an integrated AFM/Inverted Microscope. The Inverted Microscope includes all the options for Fluorescence, Phase Contrast, and standard Illumination imaging.

Included Items

• Lamp Chamber for Florescence Microscopy
• UV, V, B, G excitation Filters
• Stage with 2" X 3" microscope slide translator
• AFM Stage Adapter Plate(supplied by AFMWorkshop)
• Objectives
  • Infinity LWD plan achromatic objective 10x/0.25 WD9.67
  • Infinity LWD plan achromatic objective 20x/0.40 WD7.97,
  • Infinity LWD plan achromatic objective 40x/0.60 WD3.76
  • Infinity LWD plan phase contrast objective 20x/0.40 WD7.97
• Centering Telescope
• DIC Polarizer
• Lambda Plate
• Bulb Cover
• Phase Slide
• C- mount port
• Main Body

Not Shown

• Power supply for florescence lamp
• Power supply for illumination lamp
• Video Camera

Back and side view of the LS AFM stage without the AFM/ video microscope. The feet at the bottom may be removed if the stage is rigidly mounted to a surface.

Electronics in the LS AFM are constructed around industrystandard USB data acquisition electronics. The critical functions, such as XY scanning, are optimized with a 24-bit digital to analog converter. With the analog Z feedback loop, the highest fidelity scanning is possible. Vibrating mode scanning is possible with both phase and amplitude feedback using the high sensitivity phase detection electronics.

24 bit scan DAC

Scanning waveforms for generating precision motion in the X-Y axis with the piezo scanners are created with 24 bit DACS driven by a 32 bit micro controller. With 24 bit scanning, the highest resolution AFM images may be measured. Feedback control using the xy strain gauges assures accurate tracking of the probe over the surface.

Phase and Amplitude Detector Circuit

Phase and amplitude in the EBox are measured with highly stable phase and amplitude chips. The system can be configured to feed back on either phase or amplitude when scanning in vibrating mode.

Signal Accessible

At the rear of the EBox is a 50 pin ribbon cable that gives access to all of the primary electronic signals without having to open the EBox.

Precision Analog Feedback

Feedback from the light lever force sensor to the Z piezoceramic is made using a precision analog feedback circuit. The position of the probe may be fixed in the vertical direction with a sample-and-hold circuit.

Variable Gain High Voltage Piezo Drivers

An improved signal to noise ratio, as well as extremely small scan ranges are possible with the variable gain high voltage piezo drivers.

Software for acquiring images is designed with the industry standard LabVIEW™ programming visual interface instrument design environment. There are many standard functions, including setting scanning parameters, probe approach, frequency tuning, and displaying images in real time. LabVIEW™ facilitates rapid development for those users seeking to enhance the software with additional special features. LabVIEW also enables the LS AFM to be readily combined with any other instrument using LabVIEW.

Pre-Scan Tab

All of the functions required before making a scan are on the pre-scan tab. This includes selecting the scan mode, red dot alignment, frequency scan, and automatic tip approach.

Scanning Tab

Images are acquired using the scanning tab. Parameters selected on the scanning tab include the scan size, scan rate, GPID parameters, and the color scale used for displaying images. Included with the scanning tab is an image buffer capability that facilitates in-zooming and out-zooming.

Modes Tabs

Software control for optional modes such as MFM, EFM, and advanced F/D are found in the modes tabs. The example shown here is of the advanced F/D mode tab. This allows fine control of all the parameters controlling acquisition of force-distance curves, as well as acquisition of F-D curve maps. Mapping of curve sin this way allows the user to locate and visualize regions of the sample with varying properties, such as presence of specific molecules, or mechanical properties.

Image Analysis Software

Included with the LS AFM is the Gwyddion open source SPM image analysis software. This complete image analysis package has all the software functions necessary to process, analyze, and display SPM images.

• Visualization: false color representation with different types of mapping
• Shaded, logarithmic, gradient- and edge-detected, local contrast representation, and Canny lines
• OpenGL 3D data display: false color or material representation
• Easily editable color maps and OpenGL materials
• Basic operations: rotation, flipping, inversion, data arithmetic, crop, and resampling
• Leveling: plane leveling, profiles leveling, three-point leveling, facet leveling, polynomial background removal, leveling along user-defined lines
• Value reading, distance, and angle measurement
• Profiles: profile extraction, measuring distances in profile graph, and profile export
• Filtering: mean, median, conservative denoise, Kuwahara, minimum, maximum, and checker pattern removal
• General convolution filter with user-defined kernel
• Statistical functions: Ra, RMS, projected and surface area, inclination, histograms, 1D and 2D correlation functions, PSDF, 1D and 2D angular distributions, Minkowski functionals, and facet orientation analysis
• Statistical quantities calculated from area under arbitrary mask
• Row/column statistical quantities plots
• ISO roughness parameter evaluation
• Grains: threshold marking and un-marking, and watershed marking
• Grain statistics: overall and distributions of size, height, area, volume, boundary length, and bounding dimensions
• Integral transforms: 2D FFT, 2D continuous wavelet transform (CWT), 2D discrete wavelet transform (DWT), and wavelet anisotropy detection
• Fractal dimension analysis
• Data correction: spot remove, outlier marking, scar marking, and several line correction methods (median, modus)
• Removal of data under arbitrary mask using Laplace or fractal interpolation
• Automatic XY plane rotation correction
• Arbitrary polynomial deformation on XY plane
• 1D and 2D FFT filtering
• Fast scan axis drift correction
• Mask editing: adding, removing or intersecting with rectangles and ellipses, inversion, extraction, expansion, and shrinking
• Simple graph function fitting, critical dimension determination
• Force-distance curve fitting
• Axes scale calibration
• Merging and immersion of images
• Tip modeling, blind estimation, dilation and erosion

With the LS AFM incorporates a top view optical microscope that is useful viewing of opaque samples and aligning the laser in the light lever. The inverted optical microscope is useful for locating cells and biomaterials for scanning.

The LS AFM presents three views of e. coli, from video optical microscope, inverted optical microscope, and atomic force microscope

Inverted Light Microscope

The AFM rests on a custom design plate that facilitates direct viewing of the probe and sample with the inverted light microscope. With the inverted light microscope high resolution images of cells can be made, additional a high resolution video image of the probe at the end of cantilever can be visualized.

Top View optical microscope

Included with the LS AFM is a top view optical microscope with a 7:1 mechanical zoom tube, and a co-axial illumination source. The top view microscope is essential when using the LS AFM for imaging non-transparent samples.

The LS AFM utilizes a unique probe holder/exchange mechanism. Probes are held in place with a spring device that mates with a probe exchange tool. This combination makes changing probes fast and easy on the LS AFM.

The LS AFM is designed for the most widely used types of measurements made with an AFM, including measuring F/D curves and imaging cells in a dry and liquid environment.

Measuring Stiffness of Biomaterials

Monitoring the deflection of a cantilever as it is pushed against a sample results in a force/distance curve. From the force distance curve many parameters may be measured, such as stiffness of the sample and probe-sample adhesion.

In biological samples, the most common application is measurement of intermolecular forces. For example, this could be used to measure the interaction force between an antigen and an antibody directly. Cell-cell adhesion forces and cellular stiffness can also be measured.

The above screen shot demonstrates Advanced Force Distance Curve software measuring an AFM image.

1. Force-Distance data display region
2. Slider indicates the extension of the Z piezoelectric ceramic
3. Control parameter selection options
4. AFM Image for selecting locations for force-distance measurements

The Force/Distance Curve Measurement Software Interface includes all the features required for making advanced measurements. F/D curves may be made on single or multiple points of a sample surface. Control parameters include extend/contract rate, turn around trigger, and number of measurements per selected region.

Imaging Cells

Images of cells are readily scanned in both a liquid and dry environment with the LS AFM. The inverted optical microscope facilitates direct placement of the probe on an area of interest for scanning. Additionally the inverted microscope can be operated in epifluorescence mode.

Imaging cells in combination with an inverted optical microscope

The inverted optical microscope facilitates direct placement of the probe on an area of interest for scanning. Additionally the inverted microscope can be operated in epiflourescence mode.

Neutrophil A Cells

Inverted optical microscope image of neutrophil A cells. The dotted outline is the area scanned with the AFM.

Light Shaded AFM image of the cells visualized in the optical microscope image.

Caco-2 Cells

Inverted optical microscope image of Caco-2 cells in the LS AFM.

Clearly visible is the AFM cantilever on the right side of the image. A box identifies the area for AFM scanning.

3-D color scale image of the Caco-2 cell.

The scan range is 48 µm x 48 µm.

CACO-2 cell structure in the presence of low concentration of quantum dots.

Left: Epifluorescence, showing brightfield (red), DAPI (blue), 2.2nm quantum dot PL emission at 560nm (green).

Right: Topographic AFM image of the indicated area.

Modes included with the LS AFM:

Z Scanner for Liquid Imaging

Dunk-n-Scan cell for liquid imaging of samples

Optional LS AFM Modes:

The following modes may be purchase as options with the LS-AFM.

Conductive AFM (C-AFM)

Magnetic Force Microscopy (MFM)

Lithography

Scanning Thermal Microscopy (SThM)

Scanning Tunneling Microscope (STM)

Electric Force Microscopy (EFM)

XY Sample stage

The optional base with XY translator gives added flexibility to the LS AFM. By removing the inverted light microscope, noise floors as low as 100 picometers are achievable. The XY translator range is 12 X 12 mm with a resolution of 1 micron. At the top of the XY translator are magnets for holding standard AFM sample disks.

Vibration Solution

LS AFM Liquid Cell/Heater

The LS Heat option is a combination open liquid cell and heater that is compatible with the LS AFM. In operation, the liquid cell replaces the glass slide holder in the LS AFM.

Scanning Kelvin Probe Microscopy (SKPM)

SKPM measures the potential difference between a conductive probe and a conductive sample.

Modes

The following modes are available for the LS AFM:

Conductive AFM (C-AFM)

Magnetic Force Microscopy (MFM)

Lithography

Scanning Thermal Microscopy (SThM)

Scanning Tunneling Microscope (STM)

Electric Force Microscopy (EFM)

* Z Noise performance depends greatly on the environment in which the LS AFM operates. Best Z noise performance is obtained in a vibration-free environment. Contact AFMWorkshop for more information on our vibration isolation equipment and recommendations.

*Z Noise on the inverted microscope is <1nm.

**Every effort is made to present accurate specifications within this document. However, due to circumstances beyond the control of AFMWorkshop, specifications are subject to change without notice.