Xylem YSI 2500, Руководство пользователя

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7-2
7.2.1 D-Glucose (Dextrose)
This is a direct reading of glucose in solution at the enzyme sensor. The enzyme glucose oxidase is immobilized in the
enzyme membrane.
G O
2 Glu Oxidase
H
2
O
2
+ D-Glucono-
δ
-Lactone
System Buffer YSI 2357
Calibrator Std YSI 2776
Linearity Std YSI 1531
Membrane YSI 2365
Membrane
Color
Dark red
Detection
Range
0.05–9.0 g/L
at 13, 15 & 25
µ
L
sample size
0.05–18.0 g/L
at 10
µ
L sample size
(1.80 g/L Cal Point)
0.05–25.0 g/L
at 10
µ
L sample size
(2.50g/L Cal Point)
Calibration
Point
1.80 g/L
2.50 g/L
Linearity Check
Point
9.0 g/L
Sample Size 25 µL
End Point 30 sec
Precision
(CV,n=10) 2% or 0.02 g/L,
whichever is greater
Linearity
±
2% or 0.02 g/L,
whichever is greater
(0.05 to Cal Point)
±
5%
(Above Cal Point to
Range Max)
Typical Working
Life
21 days
Note: See Appendix B – Concentration Unit
Conversion if concentration unit conversion
is required.
Special Considerations:
•
If sample dilution is required, use reagent water.
•
If a solution must be prepared from solid glucose, use
the following diluent and allow about 15 minutes
before measuring the sample. This is required for
glucose, which must equilibrate alpha and beta
anomers (mutarotational equilibrium). If your reading
is lower than expected, you may need to wait slightly
longer for equilibration.
Diluent: 40 g/L NaH
2
PO
4
10 g/L Na
2
HPO
4
Reagent water
Both heat and the presence of phosphate accelerate
mutarotational equilibration.
•
For applications requiring linearity performance to
25.0 g/L, YSI 2777 (25.0 g/L glucose, 2.50 g/L lactate)
may be used as a linearity standard provided the
calibrator is YSI 2776 (2.50 g/L glucose, 0.50 g/L
lactate) and the sample size is 10 µL.
•
For applications requiring linearity performance to
18.0 g/L, YSI 2748 (18.0 g/L glucose, 1.78 g/L lactate)
may be used as a linearity standard provided the
sample size is 10 µL.