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!

Thank you for all your reply.

I learnt a lot from what you are suggesting.

Best all.

Zhichao