CRP-turbilatex
Latex turbidimetry 1 x 50 mL
Clinical Significance Materials Required but not Provided
CRP is an acute-phase protein present in normal serum, - Thermostatic bath at 37ºC.
which increases significantly after most forms of tissue - Spectrophotometer or photometer thermostable at 37ºC
injuries, bacterial and virus infections, inflammation and with a 540 nm filter.
malignant neoplasia. During tissue necrosis and
inflammation resulting from microbial infections, the CRP Specimen and Stability
concentration can rise up to 300 mg/L in 12-24 hours. Fresh serum. Stable 7 days at 2-8ºC or 3 months at –
20ºC.
Principle Samples with presence of fibrin should be centrifuged
CRP-Turbilatex is a quantitative turbidimetric test for the before testing.
measurement of C- reactive protein (CRP) in human serum Do not use highly hemolysed or lipemic samples.
or plasma.
Latex particles coated with specific anti- human CRP are Assay Procedure
agglutinated when mixed with samples containing CRP. 1. Bring the working reagent and the photometer (cuvette
The agglutination causes an absorbance change, holder) to 37ºC.
dependent upon the CRP contents of the patient sample 2. Assay conditions:
that can be quantified by comparison from a calibrator of Wavelength: . . . . . . . . . . . . . . . . . .540 nm (530-550)
known CRP concentration. Temperature: . . . . . . . . . . . . . . . . . 37ºC
Reagents Cuvette light path: . . . . . . . . . . . . . .1 cm
Diluent Tris buffer 20 mmol/L, pH 8.2. Sodium
(R1) azide 0.95 g/L. 3. Adjust the instrument to zero with distilled water.
Latex Latex particles coated with IgG anti-human 4. Pipette into a cuvette:
(R2) CRP, pH 10.0. Sodium azide 0.95 g/L. Working Reagent (µL) 500
CRP-CAL Calibrator. Human serum. CRP Calibrator or sample (µL) 5
concentration is stated on the vial label. 5. Mix and read the absorbance immediately (A1) and after
Optional Ref.:1102114 Control ASO/CRP/RF Level L
2 minutes (A2) of the sample addition.
Ref.:1102115 Control ASO/CRP/RF Level H
Application sheets for automated systems are
Precautions available on request.
Components from human origin have been tested and
found to be negative for the presence of HBsAg, HCV, and Calculations
antibody to HIV (1/2). However handle cautiously as (A2-A1)sample
potentially infectious.
X Calibrator concentration = mg/L CRP
Calibration (A2-A1)calibrator
Use CRP Calibrator Reference 1107002.
The sensitivity of the assay and the target value of the Quality Control
calibrator have been standardized against the Reference Control sera are recommended to monitor the performance
Material CRM 470/RPPHS (Institute for Reference Materials of manual and automated assay procedures. Controls
and Measurements, IRMM). ASO/CRP/RF Level L (Ref.: 1102114) and Level H (Ref.:
The calibration in the automated analyzer is stable for 3 1102115) are available on request.
weeks. Recalibrate when control results are out of specified
tolerances, when using different lot of reagent and when Each laboratory should establish its own Quality Control
the instrument is adjusted. scheme and corrective actions if controls do not meet the
acceptable tolerances.
Preparation
Working reagent: Swirl the latex vial gently before use. Reference Values
Prepare the necessary amount as follow: Normal values up to 6 mg/L.
- 1 mL Latex Reagent + 9 mL Diluent
CRP Calibrator: Reconstitute (→) with 1.0 mL of distilled
Each laboratory should establish its own reference range.
water. Mix gently and incubate at room temperature for 10
minutes before use.
Performance Characteristics
Storage and Stability
All the components of the kit are stable until the expiration 1. Linearity limit: Up to 100 mg/L, under the described
date on the label when stored tightly closed at 2-8ºC and assay conditions. Samples with higher concentrations
contaminations prevented during their use. Do not use should be diluted 1/5 in NaCl 9 g/L and retested again. The
reagents over the expiration date. linearity limit depends on the sample / reagent ratio, as
Reagent deterioration: Presence of particles and well as the analyzer used. It will be higher by decreasing
turbidity. the sample volume, although the sensitivity of the test will
Working reagent: Stable for 30 days at 2-8ºC. be proportionally decreased.
CRP Calibrator: Stable for 1 month at 2-8ºC or 3 months 2. Detection limit: Values less than 2 mg/L give non-
at –20ºC. reproducible results.
Do not freeze; frozen Latex or Diluent could change 3. Prozone effect: No prozone effect was detected upon
the functionality of the test. 800 mg/L.
4. Sensitivity: ∆ 4.2 mA.mg/L
5. Precision: Literature
Intra assay(n=10) Inter assay(n=10) 1. Lars-Olof Hanson et al. Current Opinion in Infect
Mean(mg/L) 8.6 16.9 50.5 8.6 16.8 50.5 Diseases 1997; 10: 196-201.
SD 0.56 0.61 0.97 0.74 1.11 3.2 2. Chetana Vaishnavi. Immunology and Infectious
CV 6.5 3.6 1.9 7.7 6.6 6.3 Diseases 1996; 6: 139 – 144.
3. Yoshitsugy Hokama et al. Journal of Clinical Lab.
6. Accuracy: Results obtained using this reagent (y) was Status 1987; 1: 15 – 27.
compared to those obtained using a commercial reagent 4. Kari Pulki et al. Sacand J Clin Lab Invest 1986; 46:
(x) with similar characteristics. 65 samples ranging from 1 606 – 607.
to 150 mg/L of CRP were assayed. The correlation 5. Werner Müller et al. Journal of Immunological Methods
coefficient (r) was 0.98 and the regression equation 1985; 80: 77 – 90.
y=0.892x + 0.282. 6. Shogo Otsuji et al. Clin Chem 1982; 28/10: 2121 –
The results of the performance characteristics depend on 2124.
the analyzer used. 7. Young DS. Effects of drugs on clinical laboratory test,
4th ed. AACC Press, 1995.
Interferences
Bilirubin (20 mg/dL), lipemia (10 g/L) and rheumatoid Manufactured by: Spinreact, S.A.
factors (300 IU/mL) do not interfere. Hemoglobin (≥ 5 Marketed By: Euro Diagnostic Systems Pvt. Ltd.,
g/L), interferes. Other substances may interfere. Millennium House, M.K.Srinivasan Nagar Main Road,
No. 144, Old Mahabalipuram Road, Perungudi, Chennai –
Notes 600 096; Email: eurods@vsnl.net, www.eurods.in
Clinical diagnosis should not be made on findings of a
single test result, but should integrate both clinical and
laboratory data.
Test Parameters
SYSTEM PARAMETERS
Mode : Two Point/Fixed time
Reaction : Ascending
Wavelength : 540 nm
Blank with : Distilled water
Sample Volume : 5 µL
Reagent Volume : 500 µL
Delay Time : 10 (Sec)
Read Time : 120 (Sec)
Calibrator : stated on the vial
Normal range : upto 6 mg/L
Linearity limit : 100 mg/L
Unit : mg/L
Notes
1.Use clean disposable pipette tips for its dispensation
Only for invitro use in Clinical laboratory (IVD)
