Microwave-based biosensor for on-chip biological cell analysis

This paper presents an innovative biosensing technique, based on the interaction between biomaterial and microwave electromagnetic (EM) waves, which probes the bio-parameters of investigated biological samples. Thanks to the microtechnologies, this approach is able to sense biomaterials down to living cells size without invasivity. The broadband dielectric spectroscopy of living cells suspensions is therefore demonstrated, sketching a rich EM signature, “rich” in terms of biological information’s such as cells’ proliferation and cells’ viability. Capacitive contrasts of 4 and 12 % between the cells suspension and their pure medium are measured at 20 and 40 GHz respectively, which demonstrate the ability of such a technique to detect (and quantify) living cells non-invasively. Moreover, we demonstrate a capacitive contrast of 5 % at 30 GHz between living and dead cells. Such a result is based on the ability of the microwaves to penetrate into the cells and sense their intracellular content, and then to carry viability information’s of biomaterials out. Finally, we present the feasibility of on-chip microwave signals processing, which points out that integrated circuit for data processing can be integrated together with a nano-liter range microfluidic bio-sample manipulation and a microwave-based biosensor. Such a work consequently permits to envision promising Lab-on-Chip applications such as cells’ drug screening for personalized medicine notably.