Assays for measurement of biologicals
The measurement of biologicals in clinical samples faces different
challenges from traditional small molecules assays, some of which are
obvious given their large and complex structures. Ligand-binding assays,
both commercially available and in-house developed, have been used for
quantifications of mAbs, including several among the ones relevant in
transplantation [2-4]. These methods can also be adapted to or
complemented with assays for the detection of anti-drug antibodies (ADA)
[3, 5]. Recent technological advances in mass spectrometry based
analysis (LC–MS/MS) have enabled the development of multiplex
bioanalysis which means that several mAbs can be analysed in the same
setup [6], as exemplified for some of the drugs that are discussed
in the following [7-10]. The detailed discussion of the analytical
challenges and pitfalls are beyond the scope of this paper, and readers
are referred to the cited reviews for details.