Preparation of Calcoflour stock solution
Ø Weigh 35 mg of Calcoflour White (C40H44N12O10S2 – = Fluorescence Brightener 28, Sigma F3543) into a 15 ml tube.
Ø Add 7 mL of distilled water and a 2-3 drops of 10N NaOH (to increase pH to 10-11). Calcofluor does not dissolve well in neutral solutions.
Ø Dissolve the calcoflour
Ø Adjust the volume to 10 mL by adding distilled water.
Ø Store this solution in a lightproof tube (preferably covered with Al-foil) at -20°C.
Ø This is a 100X solution.
P.S. For staining, one should dilute it to 1X in Tris/HCl buffer solution (0.1 M and pH 9.0). 10% glycerol and phenylene diamine as anti-fade can be added. Live cells or formaldehyde fixed cells can be stainined. Stain for 15 minutes, followed by one wash in H2O or PBS.