Thanks Michel and James (again),

The two mentioned papers are indeed close to what I was looking for. I got
a mail from IBM Zurich mentioning that it is in the process of publishing
papers related to this. Nevertheless, the doubt is solved.

If you can, take a look at A. Majumdar's article published in Nature Biot.
2001 (Volume 19, September 2001, Page 856). On page 859, in Figure 5 it
shows the variation of enzyme concentration with surface stress.

Two questions:

1) In the past 4 years, has this figure been theoretically supported?
2) Is such a figure available for any other enzyme(s)?

Thanks,
SGarg

~*~

On Fri, 20 May 2005, Michel Godin wrote:

> Hello Sudhanshu,
>
> As James pointed out, Stoney's formula is generally used to convert a
> cantilever deflection to a measure of surface stress.  Although there are
> several enhancements to this formula, it is correct to first order.  John
> Sader published several papers on the topic with much more detail and
> validation through finite element analysis.  From an experimental point of
> view, one problem with these approaches is that the cantilever's Young's
> Modulus must be known in order to use Stoney's formula.  Young's modulus for
> single crystal silicon cantilevers should be well-known, but it can be more
> difficult in the case of commonly-used SiN levers or ones coated with metal
> films.  The following paper gets around this issue by allowing one to
> calculate surface stress from the cantilever's deflection and its
> experimentally determined spring constant.
> Appl. Phys. Lett. 79, 551 (2001)