tissue culture!

[lindsey.podd]

All 

I am trying my damdest to get sterile mature explants of Nepenthes alata, 
but the material is being killed by the sterilant, while the contaminants 
are still alive and well, any ideas?  I've tried mercuric chloride, sodium 
hypochlorite (3.5%), hydrogen peroxide, benlate and other dydtemic 
fungicides..

Any help would be appriciated.

Lindsey Podd
Department of Botany,
Pietermaritzburg campus,
University of natal
South Africa