Expanding assay range to accommodate a monoclonal antibody therapeutic quantification in blood and cerebrospinal fluid

Antibody therapeutic levels in neurodegenerative diseases are often measured in both serum and cerebrospinal fluid (CSF). Due to 0.1% drug partition from serum to CSF and the higher sensitivity needs, usually two different assays are required. The different Gyrolab Bioaffy compact discs can extend the dynamic range of assays. Here, an assay was developed and adapted on two different Gyrolab Bioaffy compact discs (200 and 4000 nl) to achieve the required sensitivity and assay dynamic range needed for the measurement of drug in both serum and CSF. This was accomplished by using the same critical reagents with minimal assay development to transition from a serum to a CSF assay.