Escherichia coli OK for agglutination on glass, 3 ml, SSI Diagnostica, Denmark

Application

Diagnosis of the immune serum OK O to the E. coli from SSI Diagnostica is intended for partial serotyping by agglutination of live culture. Serum OK O is intended for screening and the result must be confirmed by O serum for boiled cultures.

 Description

Immune OK O E. coli serum is grown in rabbits and supplied in 3 ml vials. Sodium azide (to a final concentration of 0.0975%) was added as a preservative. Cross-reference reactions were eliminated, if necessary, by absorption.

 Principle

When the bacterial culture is mixed with a specific immune serum directed against the components of the surface of the bacterium, the cells are joined together by antigen-antibody bonds to form aggregates (agglutination). This is visible to the naked eye in the form of lumps in the suspension. When mixing a specific immune serum with E.coli culture, antigens O are determined.

Serum OK O is intended for the screening of live bacteria and must be confirmed by O-serum for boiled cultures.

Materials that are needed but not included in the set

• Agar medium

• Inoculation loops

• Object glass

• Physiological solution, pH 7.4

Agglutination reaction on a glass-like glass with OK O immune serum for live cultures

Serum OK O is intended for the screening of live cultures from a nonselective plate. Hypnotic and false negative results can occur if bacteria from a selective medium are used. Some selective media (for example, CSF colon, article No. 34121) do not affect agglutination.

The physiological solution is used as a negative control, and it should be negative when mixed with bacteria.

Procedure

1. The colon is grown overnight in a suitable nutrient medium.

2. Apply a small drop of immune serum (approximately 20 μl) and one drop of the physiological solution (negative control) onto the slide glass.

3. Transfer the cultures from 3-5 colonies to each drop of immune serum / saline solution and mix well. The amount of culture should be sufficient to give a distinct, muddy-colored color. Use the inoculum loop.

4. Tilt the glass and hold it for 5-10 seconds.

5. The reaction is read by the naked eye, holding the glass in front of a light on a black background (indirect light).

6. Positive reaction is considered as visible agglutination. Negative reaction is the preservation of mud-milk homogeneity. Late or weak agglutination (after 10 seconds) should be considered a negative result.

7. Positive reaction indicates that one in 3-5 colonies is positive. It is important to identify a positive colony for further analysis in order to avoid working with mixed flora.

The result OK O is the result of the screening. It is important to have group O, confirmed by agglutination with immune serum O using boiled cultures.

Storage and shelf life

Store at 2-8 ° C in a place protected from light. The expiration date is on the package. Occasionally, after prolonged storage, turbidity is observed due to precipitation of lipoproteins. Precipitations and / or contamination can be removed by centrifugation (10,000 g) followed by sterile filtration (0.22 μm).

Support for defining types

E. coli can not be identified for further study to the WHO Center for the Control and Testing of Escherichia (Escherichia) and Klebsiella, 5 Artillerivej, 2300 Copenhagen S, Denmark. Please contact us at typning@ssi.dk for payment questions.

Certificate of quality

The development of SSI Diagnostics, the production and sale of diagnostics invitroma quality assurance and certified in accordance with ISO 9001 and ISO 13485.

Delivery time: 5 days

Information updated: 03.03.2018