Rapid Allergen Test Kits: Understanding an Unexpected Negative Result

Rapid Allergen Test Kits have been developed for the detection of low allergen concentrations.

When a high concentration of a target allergen is present in a sample, this results in something called the High Dose Hook Effect.

This is often the explanation for an unexpected negative result e.g. a surface that would fail a Visual Inspection and is clearly contaminated testing negative for its target allergen.

In the following Help Guide, you will find an explanation of the High Dose Hook Effect, along with three solutions that will help you to avoid this issue.

If you are short on time, click here for a brief summary and click here for our list of solutions.

What is the High Dose Hook Effect?

An antibody antigen complex is formed when antibodies bind to the target allergen in a sample. When this complex binds to the test line, a coloured band becomes visible in the Test Window.

You will notice that each lateral flow test also has a Confirmation Window. In the case of a positive test result, a line will be visible in the Test Window and the Confirmation Window will also change colour – proof that the test is valid.   

However, high allergen concentrations result in an excess of ‘free’ allergens. This is because there are a limited number of antibodies and only a certain number of antibody antigen complexes that can form. If the free allergens bind to the test line, no colouration or only a faint line will be visible because the antibodies are missing.

In this case, the result may be interpreted as negative because only the Confirmation Window will have changed colour.  

In summary:

If a high concentration of a target allergen is present in a sample, the strip inside your lateral flow test will become overloaded with the allergen and the result of the test will appear to be negative. This is known as the High Dose Hook Effect. 

There are three possible solutions:

Diluting the sample

By diluting the sample from the testing surface, you can reduce the concentration of the target allergen. This will help you to secure an accurate test result.

To find out the correct procedure for diluting a sample, please contact the Klipspringer Technical Team on 01473461800 or sales@klipspringer.com. 

Help Guide: Preparation of Positive Control (Egg, Casein, Gluten, Soya)

Quality Control Material

Another option is to use QC Material. This is an incurred food that contains a certain amount of food allergen proteins. It can be used to replace the tested allergen but may also require dilution before use. Again, you can speak to the Klipspringer Technical Team for further information. 

Removal of excess allergen

The final option is to gently remove some of the excess allergen from the testing surface. This can be done using a clean cloth or a paper hand towel.  

Below you will find a link to our full range of Rapid Allergen Test Kits, along with a step-by-step guide to using them at your site.

Explore our full range of Rapid Allergen Test Kits
A step-by-step guide to using a Rapid Allergen Test Kit

If there are any areas where you would like further guidance, Klipspringer’s Technical Team would be happy to help with your enquiries. You can reach out to us on 01473461800 or sales@klipspringer.com.

Alternatively, you can fill out the form below and one of our in-house experts will be in touch.  

If you would like further guidance relating to Rapid Allergen Test Kits, the Klipspringer team would be happy to help. Share your details below to arrange a free consultation.