Development and validation of a method for determination of Eculizumab concentration in human plasma by biolayer interferometry

The article describes a new method for measurement of monoclonal antibody Eculizumab concentration in human plasma in a range of 3-250 μg/ml. In this method we used an antibody Fab fragment, capable of binding to eculizumab specifically in human plasma. The method uses the biolayer interferometry for determination of Eculizumab concentration without additional tag in the analyzing substances. This method was comparatively validated along with the traditional ELISA. Comparative validation demonstrated that the biolayer interferometry based method has an advantage to the ELISA in such important statistical criteria as an analytical range, accuracy, precision, specificity and selectivity (matrix effect).