Cholinesterase Gen.2

Catalog Number: 04498577190

SYSTEM INFORMATION

For cobas c 311/501 analyzers:

CHE2: ACN 510

For cobas c 502 analyzer:

CHE2: ACN 8510

INTENDED USE

In vitro test for the quantitative determination of cholinesterase in human serum and plasma on Roche/Hitachi cobas c systems.

STORAGE AND STABILITY

CHE2
Shelf life at 2-8 °C: See expiration date on cobas c pack label.
On-board in use and refrigerated on the analyzer: 4 weeks
Diluent NaCl 9 %
Shelf life at 2-8 °C: See expiration date on cobas c pack label.
On-board in use and refrigerated on the analyzer: 12 weeks

APPLICATION FOR SERUM AND PLASMA

cobas c 311 test definition
Assay type Rate A
Reaction time / Assay points 10 / 29-40
Wavelength (sub/main) 700/415 nm
Reaction direction Decrease
Units U/L (µkat/L, kU/L)
Reagent pipetting Diluent (H2O)
R1 120 µL
R3 24 µL
Sample volumes Sample Sample dilution
Sample Diluent (NaCl)
Normal 2 µL
Decreased 10 µL 15 µL 135 µL
Increased 2 µL

cobas c 501 test definition
Assay type Rate A
Reaction time / Assay points 10 / 44-54
Wavelength (sub/main) 700/415 nm
Reaction direction Decrease
Units U/L (µkat/L, kU/L)
Reagent pipetting Diluent (H2O)
R1 120 µL
R3 24 µL
Sample volumes Sample Sample dilution
Sample Diluent (NaCl)
Normal 2 µL
Decreased 10 µL 15 µL 135 µL
Increased 2 µL

cobas c 502 test definition
Assay type Rate A
Reaction time / Assay points 10 / 44-54
Wavelength (sub/main) 700/415 nm
Reaction direction Decrease
Units U/L (µkat/L, kU/L)
Reagent pipetting Diluent (H2O)
R1 120 µL
R3 24 µL
Sample volumes Sample Sample dilution
Sample Diluent (NaCl)
Normal 2 µL
Decreased 10 µL 15 µL 135 µL
Increased 4 µL

CALIBRATION

Traceability: This test has been standardized against a reference method using a manual application of the butyrylthiocholine/hexacyanoferrate (IlI) method on a manual photometer and the published molar absorptivity e of hexacyanoferrate (III).3

Calibrators S1: H2OS2: C.f.a.s.
Calibration mode Linear
Calibration frequency 2-point calibrationafter reagent lot changeas required following quality control procedures

LIMITS AND RANGES

Measuring range

100-14000 U/L (1.67-234 µkat/L)

Determine samples having higher activities via the rerun function. Dilution of samples via the rerun function is a 1:2 dilution. Results from samples diluted by the rerun function are automatically multiplied by a factor of 2.

Lower limits of measurement

Lower detection limit of the test

100 U/L (1.67 µkat/L)

The lower detection limit represents the lowest measurable analyte level that can be distinguished from zero. It is calculated as the value lying 3 standard deviations above that of the lowest standard (standard

1 + 3 SD, repeatability, n = 21).

SPECIFIC PERFORMANCE DATA

Representative performance data on the analyzers are given below. Results obtained in individual laboratories may differ.

PRECISION

Precision was determined using human samples and controls in an internal protocol with repeatability

(n = 21) and intermediate precision (3 aliquots per run, 1 run per day, 21 days). The following results were obtained:

Repeatability MeanU/L (µkat/L) SDU/L (µkat/L) CV%
Precinorm U 4887 (81.6) 25 (0.4) 0.5
Precipath U 5331 (89.0) 27 (0.5) 0.5
Human serum 1 5916 (98.8) 28 (0.5) 0.5
Human serum 2 7313 (122) 38 (1) 0.5

Intermediate precision MeanU/L (µkat/L) SDU/L (µkat/L) CV%
Precinorm U 4707 (78.6) 49 (0.8) 1.0
Precipath U 4838 (80.8) 45 (0.8) 0.9
Human serum 3 1002 (16.7) 26 (0.4) 2.6
Human serum 4 6683 (112) 74 (1) 1.1

METHOD COMPARISON

Cholinesterase values for human serum and plasma samples obtained on a Roche/Hitachi cobas c 501 analyzer (y) were compared with those determined using the corresponding reagent on a COBAS INTEGRA 700 analyzer (x).

Sample size (n) = 89

Passing/Bablok12 Linear regression
y = 1.019x - 177 U/L y = 1.018x - 178 U/L
t = 0.963 r = 0.999
The sample activities were between 2184 and 12525 U/L (36.5 and 209 µkat/L).