YSI 2700 SELECT, User Manual

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4-12
This is a direct reading of galactose in solution at the enzyme sensor. The enzyme Galactose
oxidase is immobilized in the enzyme membrane.
Gal O
2 Gal Oxidase
H
2
O
2
+ Galactose Dialdehyde Derivative
System Buffer YSI 2705
Calibrator Std n/a *
Linearity Std n/a *
Black Probe YSI 2702 Galactose Oxidase Membrane
White Probe n/a **
Sample Size 25
µ
L
Cal Station Station #1 Cal Well
Black Probe Parameters
Chemistry
Galactose
Unit of Conc g/L
Cal value user's choice (recommend about 2 g/L)
End Point 30 sec
* YSI does not currently offer galactose standard solutions.
** If you have a dual channel unit, either Black or White, or both Black and White probes can
be configured for this chemistry.
Note: See Appendix A if concentration unit conversion is required.
Special Considerations:
» If sample dilution is required, use reagent water.
»
The sample should be lactose-free. Lactose and other galactosides such as raffinose
and stachyose are substrates for galactose oxidase. They may interfere by producing
artificially high galactose readings.
» The enzyme membrane integrity test involving the use of YSI 2363 Potassium
Ferrocyanide solution is not informative since, ferrocyanide exists in the 2705 system
buffer.