I just had a quick question about culture substrates.
My supervisor wants quantitative confirmation that my cells are doing better on poly-L or collagen than gelatine before he coughs up $284 for pure type I rat tail collagen (from Sigma) as he does not have the funds. I wanted to know whether or not that was possible? By that I mean, I'm not sure whether that sort of data would be quantitative (e.g. cell density) or qualitative (cell adherence) because NSC34s will happily proliferate whether or not they are properly adhered to the surface (they are a reasonably aggressive proliferating cell line).
Please let me know what you think. Is it more of a qualitative or quantitative measure?
And which substrate would be best? Gelatin (which I've heard dissolves in modern day media over a period of 1 week) or collagen (at 0.01%) or poly-L (at 0.01%)?
Don't know that particular cell line, but you should clarify what he means by "doing better". As you say, adherence does not seem to influence proliferation, so measuring proliferation would be a quantitative measurement but not what you need. So try to ask yourself what actually made you think they might be better off with collagen/poly-lysine in the first place ? Which parameter were you thinking about ?
A possible quantitative measurement would be a viability assay - are the cells more viable if on collagen / poly-lysine ?