Stat Fax 303 Plus, Руководство оператора

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Awareness Technology, Inc. Stat Fax 303 Plus Operator’s Manual Rev. J 19
The instrument will read every well at both selected wavelengths, reporting the difference of the
two (absorbance at primary wavelength minus absorbance at differential wavelength). Be sure to
select a differential wavelength at which your chromophore has little or no absorbance;
otherwise, sensitivity may be lost.
2.1.5 Selecting a Blank
If the instrument is not “blanked”, the readings are relative to air (no well or contents). The
difference between a water blank and an air blank is typically less than 0.020A when reading
bichromatically.
The Calibrator (Single Standard) Mode requires that a blank be used in the first well of the first
strip. The Uptake Mode operates with no blank. All of the other modes offer the option of a blank
in the first well or no blank at all.
The material of choice is a reagent blank that best defines the absorbance of “zero-
concentration”.
The absorbance which is printed for a blank well is the absorbance of the blank material relative
to air. This absorbance value is automatically subtracted from subsequent absorbances before
printing and calculating.
2.1.6 Selecting Duplicates
In most modes, you have the option of reading either one well or two consecutive wells of the
blank and calibrators. When duplicates are chosen, the mean absorbance reading is used as the
reference absorbance for the blank and calibrator.
You may also choose to read specimens singly or in duplicate. If duplicate samples are selected,
the mean absorbance reading will be used to calculate the result for the pair. The reported
results for each sample are based on a single concentration value.
To make selections, use the YES and NO keys to answer questions when they are displayed. If
you select YES to the prompt
“Duplicates Y/N” , the display will show the following prompts:
“Dup Blanks Y/N” , “Dup Calbrtr Y/N” , and “Dup Samples Y/N” . You may choose duplicates
in any combination. When you have made all the selections for duplicates, select YES when the
display shows
“Done Y/N” and your selections will be printed.
Duplicates must be pipetted into consecutive wells.
Controls are read in duplicate only if the samples are selected in duplicate. When using the
controls locator feature, only label one location of the control duplicate pair. (See section 2.1.9
for more information about the controls locator feature.)
When using multi-point modes, the absorbances of duplicates will be averaged to designate a
single point. For example, consider a 3-point linear regression for which the 3 calibrators are
read in duplicate. For calculating the standard curve, n=3, n6. If one well of a pair is deleted
during an editing cycle, then the other well will represent the mean point and n=3, n2 and n5.