A methodological approach for the thermal stability and stress exposure studies of a model antibody.

The anti-horseradish peroxidase (HRP) antibody is conventionally used in immunohistochemistry. More recently, it has been used as the key element in a gold standard method to evaluate the functionality of antibody-based materials. However, few information are available about its melting temperature and its stability after exposition to laboratory stress conditions including freeze-drying and freeze-thawing cycles. The aim of this study was to evaluate the effects of these environmental constraints on the anti-HRP antibody in order to further use it as a reference in quality control and in the development of new antibody-based materials. In the developed method, the anti-HRP antibody is covalently immobilized onto a solid surface. After the direct recognition of its antigen HRP, the signal is proportional to the number of antibody active binding sites. The method was successfully utilized to accurately evaluate the anti-HRP antibody melting temperature (Tm was 73.5 ± 0.2 °C). The method is a rapid and reliable tool with minimal cost for studying the anti-HRP antibody stability to solvent stress, freeze-thawing cycles, and freeze-drying process. The obtained information may be useful for routine analysis or in the development of antibody-based materials. This can be also proposed as an easy way to control antibody freeze-drying process.