Parallelizable Microfluidic Resistive On-Line Detector of Micrometric Aggregates of Biopharmaceutical Antibodies

A microfluidic device based on the differential measurement of the ionic resistance of a micropore for detection of aggregates of antibodies in biopharmaceutical downstream process is presented. 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 μm diameter with sub-ms transit time (flow rate of 5 μl/min). Thanks to the simple PDMS fluidic fabrication, compact DC readout circuit and convenient use of the same metallic silver tubing for both electrical and fluidic interconnection, the device can be straightforwardly parallelized in tens of units, thus combining single micrometric sensitivity with larger flow rates (>100 μl/min), suitable for in-line installation in pharmaceutical plants.