YSI 2900 - 8.2.6 L-Glutamine

107
8.2.6 L-Glutamine
This is a direct reading of glutamine in solution at the enzyme sensor. Two enzymes are co-immobilized in the YSI
Glutamine Membrane: Glutaminase and Glutamate Oxidase. Through this chain of reactions the amount of hydrogen
peroxide liberated is directly proportional to the amount of glutamine.
L-Glutamine
Glutaminase
L-Glutamate + NH
3
L-Glutamate + O
2 Glut Oxidase
H
2
O
2
+ α-Ketoglutarate + NH
3
System Buffer
YSI 2357
Calibrator Std
YSI 2736
Linearity Std
YSI 2737
Membrane
YSI 2735
Membrane
Color
Magenta
Detection
Range
30–1169 mg/L
Calibration
Point
731 mg/L
Linearity Check
Point
1169 mg/L
Sample Size
20 µL
End Point
30 sec
Precision
(CV,n=5)
4% or 15 mg/L,
whichever is
greater
Linearity
±4%
(30 to Cal Point)
±5%
(Cal Point to Range
Max)
Typical Working
Life
5 days
Note: See Appendix B – Concentration
Unit Conversion if concentration unit
conversion is required.
Special Considerations:
• If sample dilution is required, use reagent water.
• The sample must be glutamate-free, or at least contain
levels low enough not to interfere with the glutamine
reading. Since the glutamine membrane contains
glutamate oxidase, glutamate will produce a probe
signal. See 8.2.18 Simultaneous L-Glutamate and L-
Glutamine to measure glutamate and glutamine
simultaneously.
• Specs shown are for simultaneous measurement of
glutamine and glutamate.