Ultra-sonic Cell Lysis

[933467u at app_science.rgu.ac.uk]

To anyone who can help me,

I'm trying to lyse cells (E.coli and S. aureus) using ultra-sonic sound 
at 30kHz, perhaps a little higher, as an alternative to "beading".  Does 
anyone out there have any experience of this sort of thing?  Can anyone 
tell me where I'm likely to find any literature about it?

Thanks for your time folks,  Alan Mercer.