Determination of NH3

[Arnoud van Vliet]

Dear Kresten,

> I am looking for a good and easy method for determining NH3. The
> sample is a pure protein (I am studying its deamidation), so
> sidereactions with other low molecular weight compounds will not be a
> problem. Would something like a OPA reaction and simple fluorescence
> measurements do?

Sigma sells (or used to sell) an ammonia detection kit (www.sigma.com).
Alternatively, look up the Berthelot reaction in chemistry books, or the
reaction described by Hamilton-Miller and Gargan (Invest. Urol. 16:327-328
(1979)). These are tests used for urease activity, which is measured by the
production of ammonia from urea.

Hope this helps
Arnoud