LaMotte SMART Spectro Spectrophotometer - Manual (Page 13)

SMART Spectro Operator’s Manual 2.11 13
Below is a list of suggested wavelength ranges for the color of the reacted
samples. Use these as a starting point.
Sample Color Wavelength Range
Yellow 350-450
Yellow-Orange 450-490
Orange 490-510
Pink 510-570
Red 570-600
Green and Blue 600-750
 CALIBRATION CURVES
The SMART Spectro contains precalibrated tests for the LaMotte reagent
systems. The fi rst step in using a non-LaMotte reagent system with the SMART
Spectro is to create a calibration curve for the reagent system. To create a
calibration curve, prepare standard solutions of the test factor and use the
reagent system to test the standard solutions with the SMART Spectro.
Plot the results (in ABS or %Transmittance) versus concentration to create
a calibration curve. The calibration curve may then be used to identify the
concentration of an unknown sample by testing the unknown, reading
Absorbance or %T, and fi nding the corresponding concentration from the curve.
The linear range of the reagent system can be determined and this information
can be used to input a User Test into the SMART Spectro (see EDIT USER
TESTS, page 35).
PROCEDURE
1. Prepare 5 or 6 standard solutions of the factor being tested. The
concentration of these standards should be evenly distributed throughout the
range of the reagent system, and should include a 0 ppm standard (distilled
water). For instance, the solutions could measure 0, 10%, 30%, 50%, 70%,
and 90% of the system’s maximum range.
2. Turn on the SMART Spectro. Select the appropriate %T/ABS wavelength from
the %T/ABS mode. Be sure to select the appropriate wavelength for the color
produced by the reagent system.
3. Use the unreacted 0 ppm standard to standardize the spectrophotometer by
using it to scan blank.
4. Following the individual reagent system instructions, react each standard
solution including 0 ppm. Record the reading and the standard solution
concentration on a chart. Readings can be recorded as percent
transmittance (%T) or absorbance (A).