Vol 3 (1) 2011 - UBM :: Departamentul de Chimie-Biologie

Carpathian Journal of Food Science and Technology 2011, 3(1), 7- 11
comparatively small number independent
statistic observations (EA-4/02)
The compound uncertainty has
been calculated from the report between
the extended uncertainty U and the
covering factor which at a probable
coverage of 95% is in most of the cases 2
U
u cA
= (6)
k
and the relative uncertainty has been
obtained in the proportion between the
compound uncertainty
u
c
u
rA
= (7)
-
x
Table 2 presents the data of the
uncertainties of Type B for the
measurement instruments, in all the cases
the covering factor k is 2 for a covering
probability of 95%.
Size
Operation
Table 2. Uncertainty data of Type B
Instrument of
measuring
Extended
uncertainty
U
Compound
uncertainty
u cB
Relative
uncertainty
u rB
M measuring XT120A scale 0.2 mg 0.1 0.02
V1 Extraction
Measuring pipette
class AS - 10 ml
0.05 ml 0.025 0.0027
V2 Extract assay Micropipette 50 µl 0.1 0.05 0.001
V3
Dilution Micropipette 150
extract
µl
0.5 0.25 0.0003
V4
Assay for
analysis
Micropipette 50 µl 0.1 0.05 0.001
V5
Blanc Micropipette 100
preparation µl
0.5 0,.25 0.0025
V6
Adding
conjugate
Micropipette 25 µl 0.1 0.05 0.002
V7
Preparing
etalon
Micropipette 50 µl 0.1 0.05 0.001
V8
V9
A
Washing
Stopping the
reaction
Reading at
ELISA
apparatus
Micropipette 100
µl
Micropipette 100
µl
ELISA
SINNOWA
0.5 0.25 0.0025
0.5 0.25 0.0025
0.001 0.005 8.3x10 -7
u
2Br
=
11
∑
u
2
Bri
= uBrM
2
+ uBrV1
+ uBrV2
2
2
2
i= 1 uBrV8 + uBrV9 + uBrA =
2
2
0.0355
+ uBrV3
2
+ uBrV4
2
+ uBrV5
2
+ uBrV6
2
+ UBrV7
(8)
2
+
10