App note: AN4 Label-free quantification in bioproduction samples

By October 1, 2021May 16th, 2022No Comments

Application note 4 | Version 2 | Kris Ver Donck², Dagmara Minczakiewicz²,
Kim Stevens², Gert Struys¹, Thomas Geuens¹, Koen Dierckx¹, Filip Delport²



This application note demonstrates the potential of FOx BIOSYSTEMS’ fiber-optic surface plasmon resonance technology (FO-SPR) for label-free quantification of an antibody in cell culture media. We demonstrate the detection of a monoclonal IgG produced using a continuous perfusion platform. As an example system, we used the therapeutic monoclonal antibody, Trastuzumab (TRA), also known as Herceptin® which is used for the treatment of HER-2 positive tumors.

The methods described here demonstrate that FO-SPR can detect relevant concentrations of TRA in samples obtained from a bioreactor. TRA levels in the samples ranged from 5.8 to 139.1 µg/ml. A calibration curve from 0.31 to 12.5 µg/ml Herceptin® was constructed by making serial dilutions in blank cell culture media. There is an excellent correlation between results obtained by FO-SPR and those using an optimized ELISA technique (Spearman correlation up to 0.992).

We discuss here how the FO-SPR label-free assay can provide a fast and performant alternative to ELISA for the analysis of biomolecules in crude samples with minimal processing, thereby showing great potential as an R&D and analysis tool for bioproduction development.