IDS IDS-iSYS, Руководство пользователя

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1-5- Operating principles
Depending on the type of analysis, the uses the following measurement principles:
•
Luminescence measurements carried out in the luminometer.
•
Absorbancy measurements carried out continuously by the spectrophotometer.
Depending on the type of the assay, Immunoassays using the chemiluminescence method are measured by
the luminometer and by the spectrophotometer for enzymatic detection assays.
BIochemistry assays are measured by the spectrophometer.
1-5-1- Luminescence measurements
By-products of luminescent acridinium esters are used as detection markers (DMAE - dimethylethanolamine).
The acridinium esters emit light after reacting with hydrogen peroxide and an alkaline solution. IDS-iSYS
Trigger A contains hydrogen peroxide in a dilute acid medium, and IDS-iSYS Trigger B contains a solution of
dilute sodium hydroxide. The analyser automatically injects trigger solutions A and B into the reaction cuvette,
which results in the oxidation of the ester into an excited form. The return to a stable state is accompanied by
the emission of light which is measured and is expressed in relative light units (RLU) by the luminometer
integrated in the analyser.
1-5-2- Absorbancy measurements
Photometric measurements are carried out in the reaction cuvette (maximum interval between two consecutive
measurements is 25 seconds).
These measurements are carried out at the wavelength specific to the analysis, defined in the parameters.
In monochromatic light and at constant temperature, the relationship between absorbancy (or optical density -
OD) and the concentration of the analyte is provided by the BEER-LAMBERT law:
OD = ε l C with OD = Log
I 0
I
Where:
•
I
0
Light flow at cuvette entrance.
•
I Light flow at cuvette exit.
•
ε Molar extinction coe ffi cient of the analyte (in L.mol -1 .cm -1 ).
•
l Optical pathway (cm).
•
C Concentration of analyte (Mol.L -1 ).
Absorbancies are measured with an optical pathway of 0.8 cm and corrected for an optical pathway of 1 cm.
Operating principle
1-5- Operating principles
IDS-iSYS User Manual - Revision M1
Operating principle 1-5
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Software version V 14