Question
Asked 8 July 2015

How can I calculate the Young's modulus of a soft bio-sample via the single molecule force microscopy curves?

I have got the single molecule force microscopy curves of this bio-sample, but I do not know how to calculate the young's modulus from these curves. 
Can anyone be kindly to tell me how? Specific reference are welcome.
Best,

All Answers (3)

Sebastian Aguayo
Pontifical Catholic University of Chile
Hi,
Unless during experimentation you performed effective nanoindentation of your molecules, with a sufficient load to record some degree of deformation, you will not have that data available in your force curves as your data will mostly be the adhesion between the molecule and surface.
If you do obtain adequate indentation data in your curves, as the previous responder suggested, you should estimate YM by employing a specific model. Hertzian is usually employed, but I would suggest you look into the DMT model as it seems to be more appropriate for biological samples.
Good luck!
Zhichao Lou
Nanjing Forestry University
Thank you for all your reply.
I learnt a lot from what you are suggesting.
Best all.
Zhichao

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