NanoPhotometer
®
P-Class
User Manual
Version 2.1
Page 48 / 70
5.5
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:
Parameter Screen
Parameter Screen
Step 1
Press 3 to select
Functions.
Step 2
Press 5 to select
Standard Curve
Step 3
Select the
Wavelength
using the keypad numbers or left
and right arrows.
Step 4
Enter the number of
Standard
concentration points to be
used in the curve (1-9).
Step 5
Units:
The user can enter a text string up to 8 characters
long. To access a list of pre-defined units press the
Menu/Options
key and then use the left/right arrows
(µg/ml, µg/µl, pmol/µl, mg/ml, 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
.
Step 6
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.
Step 7
Select the
Calibration
mode: either
Standards
(measure
prepared standards) or
Manual
(keypad data entry) or
New
S
tandards
(previous values are blanked, new
standard can be measured).
Step 8
(if standards selected) Select the number of standards to
be measured and averaged at each standard
concentration point. Can be Off (1), 2 or 3.
Step 9
Press
Next
to enter the Standards screen OR Press
Cancel
to cancel selections and return to the
Functions
folder.