Two-component dielectric dispersion impedance biosensor for in-line protein monitoring

In current contribution we demonstrate an impedance spectroscopy microfluidic sensor that is able to characterize protein solutions in a broad frequency range corresponding to beta and delta dielectric dispersion regions. The primary application of the described sensor is an in-line monitoring within bioprocesses where the real-time detection of drifts of technological parameters is highly demanded for the immediate feedback influence. The sensor utilizes the detection of volumetric properties without the application of immobilization coatings. It conducts non-destructive and non-invasive analysis of volumetric dielectric properties of protein solutions directly in a flow. It primarily analysis the dielectric spectrum in a broad frequency range where protein complex dielectric relaxation mechanisms are involved and restore information about the predefined protein solution (such as protein concentration monitoring). The sensor allows a continuous volumetric in-line analysis of protein solutions without interruption for re-calibration or purification. However, the manufacture of the proposed sensor is associated with several technological challenges. In current contribution we describe the technology of the sensor fabrication process and report the indicative experimental results of monitoring of bovine serum albumin (BSA) protein solution in phosphate-buffered saline (PBS). (C) 2016 Elsevier B.V. All rights reserved.