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P a g e
Step 1
Select the wavelength using the keypad numbers or
left and right arrows.
Press the down arrow.
Step 2
Enter the number of standard concentration points to
be used in the curve (1-9).
Press the down arrow.
Step 3
Units: The user can enter a text string up to 8
characters long. To access a list of pre-defined units
press the Options key
and then use the
left/right arrows (µg/ml, µg/µl, pmol/µl, mg/dl, mmol/l,
µmol/l, g/l, mg/l, µg/l, U/l, %, ppm, ppb, conc or
none). These units can also be edited once OK is
pressed.
This screen also allows the number of displayed
decimal points (DP) to be selected, from 0 to 2 Note
that the result will always be fixed to 5 significant
figures regardless of how many decimal points are
selected (so 98768.2 will display as 98768 even with
1 decimal point selected). Press OK
to store
the chosen parameters or Cancel
.
Press the down arrow key.
Step 4
Select the type of curve fit using the left and right
arrows. Options: straight line regression, a zero
regression (this forces the straight line through the
origin), interpolated or cubic spline.
Press the down arrow key.
Standard Curve
The construction of a multi-point calibration curve from standards of known concentration to quantify unknown samples is
a fundamental use of a spectrophotometer; this instrument has the advantage of being able to store this curve as a
method, using up to 9 standards.
To include a zero concentration standard, include this in the number of standards to be entered and enter 0.00 for
concentration; use a reagent blank when required to enter the zero standard.
The procedure is as follows:
