Hi,
I'll soon be doing a click chemistry reaction which calls for 10% of the reaction solution to be a 1M Tris buffer of pH 8.5.
Assuming that I want 200ml of the buffer and use solid Tris with 1M HCl I would prepare in the following way:
(See my calculation below)
So I come up with:
24.23g Tris
68ml 1.0M HCl
BTV 200ml with H2O
Then titrate to pH 8.5.
Questions:
1) Can I autoclave the buffer?
2) I really only need about 250ul of this Tris buffer per experiment run. Can I store the rest for future use and is room temp ok? or -4C, -20C, -80C?
Calculations:
200ml of 1M Tris @ pH 8.5. & 1M HCl stock
200ml(1/103ml)(121.14g/mol) = 24.23g Tris
pH=pKa + log([A]/[HA])
[A]/[HA] = 10ph-pKa = 108.5-8.21 = 100.26 = 1.95
[HA] = 1/2.95
[H+] = (1/2.95)(1M) = 0.34M
C1V1=C2V2
V1(HCl) = C2V2/C1 = (0.34M)(200ml)/(1.0M) = 68ml 1.0M HCl
So I come up with:
24.23g Tris
68ml 1.0M HCl
BTV 200ml with H2O
Then titrate to pH 8.5.
