Spectroquant Pharo 300 - Page 238

114739
Cell Test
Measuring 0.010 – 2.000 mg/l NH
4
-N
range: 0.01 – 2.58 mg/l NH
4
0.010 – 2.000 mg/l NH
3
-N
0.01 – 2.43 mg/l NH
3
Expression of results also possible in mmol/l.
Ammonium
Pipette 5.0 ml of the
sample into a reaction
cell
close with the screw
cap,
and mix.
Add 1 dose of NH
4
-1K
using the blue dose-
metering cap, close the
cell with the screw cap.
Shake the cell vigorous-
ly to dissolve the solid
substance.
Reaction time:
15 minutes
Place the cell into the
cell compartment. Align
the mark on the cell with
that on the photometer.
Important:
Very high ammonium concentrations in the sample
produce turquoise-colored solutions (measurement solu-
tion should be yellow-g
reen to green) and false-low read-
ings are yielded. In such cases the sample must be di-
luted (plausibility check).
Check the pH of the
sample, specified range
:
pH 4 – 13.
If required, add dilute
sodium hydroxide
solution or sulfuric acid
drop by drop to adjust
the pH.
Release 06/2014 - Spectroquant
®
UV/VIS Spectrophotometer Pharo 300
Quality assurance:
To check the measurement system (test reagents, meas-
urement device, and handling) w
e recommended to use
Spectroquant
®
CombiCheck 50, Cat.No. 114695, or the
Standard solution for photometric applications, CRM,
Cat.No. 125022 and 125023.
Ready-for-use ammonium standard solution Certipur
®
,
Cat.No. 119812,
concentration 1000 mg/l NH
4
+
, can also
be used after diluting accordingly.
To check for sample-dependent effects the use of addition
solutions (e.g. in CombiCheck 50) is highly recommended.