Do not freeze: frozen ASO – Latex and Diluent could
change the functionally of the test
Bring reagents at Room Temperature before use
Anti-Streptolysin O
Quantitative Turbidimetric Method
PRINCIPLE:
The “ANTI STREPTOLYSIN O” kit is a quantitative
turbidimetric test for the measurement of ASO in human
serum or plasma.
Latex particles, coated with streptolysin O (SLO), are
agglutinated when mixed with samples containing ASO.
The agglutination causes a turbidity whose absorbance
change, dependent upon the ASO contents of the sample
that can be quantified by comparison from the calibrator of
known ASO concentration.
The sensitivity of the assay and the target value of the
calibrator have been standardized against the ASO
International Calibrator (WHO).
It is not recommended the use of other commercially
available ASO calibrators
Reagent composition
1. Diluent
TRIS buffer
pH 8.2
20 mmol/l
Sodium Azide
0.95 g /l
2. Latex
Latex particles coated with streptolysin O
pH 10
Sodium Azide
0.95 g /l
3. Calibrator
Human Serum
Value stated on vial label
Sodium Azide
0.95 g/l
According to the present laws the kit does not contain
substances classified as dangerous
Storage and Stability of Reagents
Store the kit at 2 - 8°C
All the components are stable until the stated expiration
date if stored tightly closed and refrigerated
Preparation and Stability of Working solution
Diluent
liquid and ready to use
Latex
liquid and ready to use
Calibrator:
liquid and ready to use
WORKING SOLUTION
Swirl the Latex vial gently before use and prepare the
necessary amount of Working solution as follow:
1ml Latex + 9 ml Diluent
Working solution stability: 30 days at 2 - 8°C
Reagents deterioration: Presence of particles and turbidity
Sample
Fresh serum
Do not use highly hemolized or lipemic samples
Samples with presence of fibrin should be centrifuged
before testing
The sample is stable 7 days at 2-8°C or 3 months at-20° C
Caution
BIOLOGICAL RISK
Each unit of source material used in the preparation of the
Calibrator have been tested by a licensed method and
found non reactive for HbsAg and negative for Antibodies
to HCV and HIV 1/2.
However no known test can offer complete assurance that
products derived from human blood will not transmit
Hepatitis, AIDS or other infectious diseases. Those
products, like all materials of human origin, should be
handled as potentially infectious biological material
Safety precautions
For in vitro diagnostic use only
Do not pipette by mouth.
Exercise the normal precautions required for handling
laboratory reagents.
Procedure
Wavelenght:
540 nm (530 - 550)
Cuvette
light path: 1cm
Temperature
37°C
Adjust the instrument to zero against distilled water
Pipette into cuvettes
Calibrator
Sample
Working Solution
1 ml
1 ml
Calibrator
10 µl
Sample
10 µl
Mix and read the first absorbance of Calibrator and
Samples (A1) immediately and after 2 minutes read the
second absorbance (A2).
Calculation
(A2 - A1) Sample
ASO (IU/ml) =
x Calibrator Value
(A2 - A1) Calibrator
Reference values
Adults
up to 200 IU/ml
Children < 5 years old
up to 100 IU/ml
These values must only be used as a guideline.
Each laboratory should establish its Normal Reference
Range
Performance Characteristics
1. LINEARITY LIMIT
Up to 800 IU/ml under the described assay conditions.
Samples with higher values should be diluted 1:3 with
Saline Solution and retested again. Multiply the result by 3.
The linearity limit depends on the sample/reagent ratio, as
well the analyzer used.
It will be higher by decreasing the sample volume, although
the sensitivity of the test will be proportionally decreased.
2. DETECTION LIMIT
Values less than 20 IU/ml give non - reproducible results
3. PROZONE EFFECT
No prozone effect was detected upon 3000 IU/ml
4. PRECISION
Mean (IU/ml)
SD
CV
Intra - Assay (n = 10)
135
236
372
3.4
5.4
5.9
2.5
2.3
1.6
Inter - Assay (n = 10)
135
236
372
7.9
13.2
17.7
5.9
5.5
4.8
5. ACCURACY
Comparing this reagent (y) with another commercial one (x)
were obtained the following results:
N = 80
r = 0.98 y = 1.305 x - 7.65
6. INTERFERENCES
Bilirubin up to 20 mg/dl does not interfere
Haemoglobin up to 10 g/l does not interfere
Lipaemia up to 10 g/l does not interfere
Rheumatoid Factors up to 600 IU/ml do not interfere
Other substances may interfere7
Quality Control
Control Sera are recommended to monitor the performance
of manual and automated assay procedures.
Note
Clinical diagnosis should not be made on findings of a
single test result, but should integrate both clinical and
laboratory data
Bibliography
1. Haffejee I. Quarterly Journal of Medicine, New series 84;
305: 641- 658 (1992)
2. Alouf Jodeph E.: Pharma Ther; 11, 681 - 717 (1980)
3. Fasani M et al.: Eur. J. Lab. Med.; vol.2 n° 1: 67 (1994)
4. Todd E.W.: J. Exp. Med.; 55: 267 - 280 (1932)
5. Klein GC. Applied Microbiology; 19: 60 - 61 (1970)
6. Klein GC. Applied Microbiology; 21: 999 - 1001 (1970)
7. Young D.S.:Effects of Drugs on clinical laboratoty test,
4th ed.AACC Press (1995)
For in vitro diagnostic use only.
The following symbols are used on labels
For in vitro diagnostic use
Use by (last day of the month)
Temperature limitation
Batch Code
www.betalab-eg.com