Human HumaStar 600, User Manual

Page: 87 / 132

defInItIon of metHodS
83
If no correction is applied, formula becomes
M = (A
2
- A
1
) - B.
where B is the measurement of the reagent blank if required, otherwise set to 0.
The reagent blank determination is analogous to sample reaction.
If extra precision is required, readings are computed as the average of the first
and extra precision readings as
M = ((A
2
+ Ae
2
) / 2 - (A
1
+ Ae
1
) / 2) - B.
Limitations
Reagent times for R2/R3 shall be greater than 0.
Extra precision
Other absorbance readings (Ae
1
and Ae
2
) may be taken immediately after each
reading.
6.1.2 FIXED POINT
Readings
The first and second absorbance readings (A
1
and A
2
) are taken at specified times
(NT1 and NT2) after last reagent addition. Real reading times in seconds since
last reagent addition are observed (RT
1
and RT
2
).
Measurement
The measurement is calculated as
M = ((A
2
- A
1
) · (NT
2
- NT
1
) / (RT
2
- RT
1
)) - B.
where B is the measurement of the reagent blank if required, otherwise set to 0.
The reagent blank determination is analogous to sample reaction.
If extra precision is required, absorbance readings are interpolated from Ae
i
at
RTe
i
and A
i
at RT
i
as
AI
i
= Ae
i
+ (A
i
- Ae
i
) / (RT
i
- RTe
i
) · (NT
i
- RTe
i
)
and measurement is calculated as
M = (AI
2
- AI
1
) - B.
Extra precision
Absorbance readings (Ae
1
and Ae
2
) are taken 6 seconds before NT
1
and NT
2
. Real
reading times since last reagent addition are observed (RTe
1
and RTe
2
).