Dear Amro,
What you could try is this. Make a solution of 0.5 % (w/v) commassie
brilliant blue in 10% (v/v) ethanol in water. Pipet 1 ul of this into
your drop and close the cover slip. If the crystals are protein, they
should turn blue after some time (typically 30 mins). Salt crystals will
not turn blue as they are not stained by commassie.
You could also try using Hampton's Izit crystal dye for this, but the
problem I have faced with it is that the izit itself crystallizes (gives
lovely blue crystals) under certain buffer conditions.
cheers
Ganesh
Hallo my colleagues.
i hope every one doing ok . i did screening since two weeks . i
noticed today this crystals. i don`t know either it salt or protein
crystal . my protein has zero tryptophan so i could distinguish by UV
camera.
the condition was conditions:
0.1M SPG buffer pH 8 and 25%PEG 1500. in addition to Nickle chlorid 1mM.
best regards
Amr
