Forums
Bruker Media
Community Media
Bruker AFM Probes
SPM Digest
Application Notes
NanoTheater
Website
中文
Brochures & Datasheets
Publications
Probes Catalog
Events
Manuals & Documentation
Presentations
Guide to AFM Modes
News
Journal Club
Webinars & Video
Nanovations
Other
1.Do we need to ensure the number of peaks in ETD to be just 1 when estimating tip radius from this height? Actually, I found the tip radius estimated in the absolute method far below the nom value (at least 5 times smaller), after inputting the average deformation into the Height 1 from Apex field.
2. By the way, I've tried both the image roughness value and bearing depth value as the average deformation, but neither of them gave a good result.
Did anyone have similar problems?
Hi, Fenny,
You can send me your files and screen shot of your settings so that I can advise, you should have my email :)
For average deformation, just a rough estimation will work, you can just use section analysis to get an idea of mean deformation. For bearing depth analysis, you need to set bearing area to be 50% under area percent (beside input) to see average (median actually). Roughness should give you overall mean or mean of specified area. Let me know if you have further questions.
LA
After check your file, I found you have two issues with your problem. firstly, the image of RS looks very bad, since your tips have been used to do QNM on cells, I guess it pretty likely has been contaminated and you can't rely on such result for an accurate calibration. Secondly, you can't use this 'absolute method' to calibrate a soft probe for cell modulus measurement, you can't get same deformation on such hard calibration sample as on your cells. So you have to rely on 'relative method' to estimate your tip radius at same order of indentation depth. The soft material recommended for kPa level calibration is Agarose gel, for its preparation and characterization you can refer to this paper 'Probing mechanical properties of living cells by atomic force microscopy with blunted pyramidal cantilever tips' PHYSICAL REVIEW E 72, 021914 2005.