C-Reactive Protein Gen.3

Catalog Number: 04956842190

SYSTEM INFORMATION

For cobas c 311/501 analyzers:

CRPL3: ACN 210

For cobas c 502 analyzer:

CRPL3: ACN 8210

INTENDED USE

Immunoturbidimetric assay for the in vitro quantitative determination of CRP in human serum and plasma on Roche/Hitachi cobas c systems.

STORAGE AND STABILITY

CRPL3
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
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 2-Point End
Reaction time / Assay points 10 / 8-18
Wavelength (sub/main) 800/570 nm
Reaction direction Increase
Units mg/L (nmol/L, mg/dL)
Reagent pipetting Diluent (H2O)
R1 150 µL
R2 48 µL 24 µL
Sample volumes Sample Sample dilution
Sample Diluent (NaCl)
Normal 2 µL
Decreased 4 µL 25 µL 75 µL
Increased 2 µL

cobas c 501 test definition
Assay type 2-Point End
Reaction time / Assay points 10 / 13-29
Wavelength (sub/main) 800/570 nm
Reaction direction Increase
Units mg/L (nmol/L, mg/dL)
Reagent pipetting Diluent (H2O)
R1 150 µL
R2 48 µL 24 µL
Sample volumes Sample Sample dilution
Sample Diluent (NaCl)
Normal 2 µL
Decreased 4 µL 25 µL 75 µL
Increased 2 µL

cobas c 502 test definition
Assay type 2-Point End
Reaction time / Assay points 10 / 13-29
Wavelength (sub/main) 800/570 nm
Reaction direction Increase
Units mg/L (nmol/L, mg/dL)
Reagent pipetting Diluent (H2O)
R1 150 µL
R2 48 µL 24 µL
Sample volumes Sample Sample dilution
Sample Diluent (NaCl)
Normal 2 µL
Decreased 4 µL 25 µL 75 µL
Increased 4 µL

CALIBRATION

Traceability: This method has been standardized against an internal method traceable to CRM 470 (RPPHS - Reference Preparation for Proteins in Human Serum).12

Calibrators S1: H2OS2: C.f.a.s. Proteins
Multiply the lot-specific C.f.a.s. Proteins calibrator values by the factors below to determine the standard concentrations for the 6-point calibration curve:
S2: 0.10000 S5: 2.0000
S3: 0.3325 (c 501/502) 0.3500 (c 311) S6: 4.0000
S4: 1.0000
Calibration mode 6 point spline
Calibration frequency Full calibrationafter reagent lot change as required following quality control procedures

LIMITS AND RANGES

Measuring range

0.3-350 mg/L (2.9-3333 nmol/L)

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

Lower limits of measurement

Limit of Blank (LoB) and Limit of Detection (LoD)

LoB = 0.2 mg/L (1.9 nmol/L)

LoD = 0.3 mg/L (2.9 nmol/L)

The Limit of Blank and Limit of Detection were determined in accordance with the CLSI (Clinical and Laboratory Standards Institute) EP17-A requirements.

The Limit of Blank is the 95th percentile value from n > 60 measurements of analyte-free samples over several independent series. The Limit of Blank corresponds to the concentration below which analyte-free samples are found with a probability of 95 %.

The Limit of Detection is determined based on the Limit of Blank and the standard deviation of low concentration samples.

The Limit of Detection corresponds to the lowest analyte concentration which can be detected (value above the Limit of Blank with a probability of 95 %).

Limit of Quantitation (Functional sensitivity)

0.6 mg/L (5.7 nmol/L)

The Limit of Quantitation was determined using the result of functional sensitivity testing. The Limit of Quantitation (functional sensitivity) is the lowest CRP concentration that can be reproducibly measured with an interassay coefficient of variation of < 20 %. It has been determined using low C-reactive protein samples.

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 Meanmg/L (nmol/L) SDmg/L (nmol/L) CV%
CRP T Control N 3.35 (32.4) 0.04 (0.4) 1.2
Precipath Protein 44.4 (422) 0.6 (5) 1.3
Human serum 1 0.57 (5.71) 0.02 (0.19) 3.6
Human serum 2 1.56 (15.2) 0.03 (0.3) 1.6
Human serum 3 43.2 (411) 0.5 (5) 1.2

Intermediate precision Meanmg/L (nmol/L) SDmg/L (nmol/L) CV%
CRP T Control N 3.06 (29.1) 0.09 (0.9) 2.9
Precipath Protein 43.6 (415) 0.8 (8) 1.9
Human serum 1 0.51 (4.86) 0.06 (0.57) 11.1
Human serum 2 1.44 (13.7) 0.06 (0.6) 3.9
Human serum 3 41.3 (393) 0.7 (7) 1.7

METHOD COMPARISON

CRP values for human serum and plasma samples obtained on a Roche/Hitachi cobas c 501 analyzer (y) were compared to those determined with the Tina-quant CRP (Latex) assay on a Roche/Hitachi 917 analyzer (x).

Sample size (n) = 68

CRP values for human serum and plasma samples obtained on a Roche/Hitachi cobas c 501 analyzer (y) were compared to those determined with the CRPL2 reagent on a COBAS INTEGRA 800 analyzer (x).

Sample size (n) = 69

Passing/Bablok18 Linear regression
y = 1.014x + 0.106 y = 1.008x + 0.422
t = 0.987 r = 0.999
The sample concentrations were between 0.220 and 208 mg/L (2.09 and 1980 nmol/L).

Passing/Bablok18 Linear regression
y = 0.941x + 0.166 y = 0.928x + 1.28
t = 0.983 r = 0.998
The sample concentrations were between 0.525 and 221 mg/L (5.00 and  2104 nmol/L).