Parallelizable Microfluidic Resistive On-Line Detector of Micrometric Aggregates of Biopharmaceutical AntibodiesM. Carminati1, M. Giacometti1, M. Sampietro1, S. Chiodini2, T. Doles3, G. Ferrari1
1. Politecnico di Milano – DEIB, Milano, Italy – 2. National Systems, Somma Lombardo (VA), Italy 3. Lek Pharmaceuticals d.d., Mengeš, Slovenia
Among several efforts oriented to bringing microfluidic technology from the lab to the industry, we present a microfluidic device based on the differential measurement of the ionic resistance of a micropore (Coulter-type 10 by 16 by 25 mm3) for detection of aggregates of antibodies in biopharmaceutical downstream process (Fig. 1).
The main novelty of this contribution regards the experimental demonstration that, despite the poor solidness of proteins, their aggregates, in their standard production buffer, can be electrically detected down to 2.4 um diameter with sub-ms transit time (flow rate Q= 5 ml/min).
Thanks to the simple PDMS fluidic fabrication, compact DC readout circuit and convenient use of the same metallic Ag tubing for both electrical and fluidic interconnection (Fig. 2), the device can be straightforwardly parallelized in tens of units, thus combining single micrometric sensitivity with larger flow rates (>100 ml/min), suitable for in-line installation in pharmaceutical plants.