[ACA]

One of life's minor irritations is the weighing of small quantities of
statically charged substances (e.g. peptides).

The methods to circumvent this problem are:

1) Sometimes helps using a commercial laundry cloth (Bounce) to
wipe the outside of the receiving vessel, the glass balance doors, the
containing vessel and the balance knobs [1]

2) Use anti-static pistol Zerostat (ca. $70). You can find it in
Internet or in some shops dealing with Audio/TV. It is also available
from some chemical suppliers (e.g. Aldrich), but the price is slightly
higher. The unit operates on the piezoelectric effect to emit a stream
of charged ions which completely neutralizes all surface static over a
30-cm area. [2]

3) There are anti-static devices that contain radioactive strip, but
I have never heard a positive opinion (also it doesn't mean that they
don't work in some cases).

[1] Aldrichimica Acta (1981) Vol. 14, No. 2, p. 22

[2] Aldrichimica Acta (1981) Vol. 14, No. 4, p. 62

removal statical electricity charged crystals compound substances electrostatically charged

[mtburk]

The balance error and long equilibration times caused by static can be avoided entirely by weighing powders on a piece of Al-foil rather than weighing paper. It simply grounds the charge to the balance pan. Any conductive substance will do the same.
Be aware that some chemicals (strong alkali, Hg salts, etc) will react with Al, so use good judgement.

I find that this is far more effective than static guns, but doesn't help you get the staticy powder out of the bottle.

Radioactive strips work nicely in our glove box, the worst possible static environment in humidity terms. Just be aware that it is a relatively short half life isotope, and must be replaced from time to time.

[Guest]

Thanks a lot, it is a very useful note!

Do you have any experience:

1)How significant is a balance error caused by static?

2) Do you think grounding the charge to the balance pan can cause errors either? May be to ground it before weighing to something else? Or did you check that this does not make a difference?

Thanks in advance.