GLP Research Unit – Skin sensitization – Buehler test according to PN-EN ISO 10993-10:2015-02

The Buehler test, or Buehler patch test, is an in vivo test to assess skin sensitization. It is one of the methods for biological evaluation of medical devices from the PN-EN ISO 10993 group of standards in addition to the in vivo maximization test (GPMT). It is used to evaluate the skin sensitization potential of various chemicals, medical devices or medicinal products.

Skin sensitization is an allergic reaction that occurs when the immune system reacts to a substance after previous exposure, causing symptoms such as redness, itching and inflammation after subsequent contact. In vivo studies using a small animal model, such as biocompatibility assessments, are conducted in our unit at the Facility for Small Animal under the GLP standard. With a standard like GLP, we can ensure that experiments are performed at the highest quality level.

The Buehler sensitization test consists of the following phases:

Induction phase: During this phase, the test substance, such as an extract from a medical device, is applied to the skin of an animal model, often a rodent. The test substance is applied in the form of a patch along with an adjuvant that enhances the immune response.

Rest phase: The initial exposure is followed by a rest period during which the immune system recognizes and sensitizes itself to the substance.

Provocation phase: In the provocation phase, animals are re-exposed to the same substance, usually at a different site on the skin. The provocation exposure is designed to assess whether an allergic reaction will occur after re-exposure.

Scoring and evaluation: skin reactions, such as erythema (redness), swelling (puffiness) and other signs of irritation, are evaluated and compared to control groups. The severity and frequency of skin reactions help determine whether the test substance has caused a sensitizing effect.

The Buehler test is a useful method in the biological evaluation of medical devices because of its compliance with GLP regulations. It provides assurance that the evaluation of the biocompatibility of a substance or medical device is carried out according to the highest quality standards and ensures the safety of products used in contact with the human body.

We are certified by Good Laboratory Practice in the biocompatibility section (scope 9) for the biological evaluation of medical devices for in vivo testing on both small and large animal models, among others.

Feel free to contact us to match the appropriate testing method to your medical device.