vitelline removal

[CLANCY David]

Hi all,
	I'm having fearful trouble removing the vitelline membrane from 
D. serrata (melanogaster group) embryos. Simulans is fine. I'm shaking in 
a 50/50 soln of n-heptane and 80% ethanol. If I use 100% methanol it 
makes no difference. I get very few falling out of the organic layer.
Any suggestions?

thanks

David Clancy
genetics
la Trobe Uni.
Melbourne, Australia