Enhancing Cell Characterization via Hydrodynamic Compression in Suspended Microchannel Resonators

TL;DR

This paper introduces a novel hydrodynamic compression method to improve nanomechanical resonator sensors for cell characterization, enabling better detection limits and differentiation of cell lines based on physical properties.

Contribution

It presents an analytical study and experimental validation of hydrostatic compression effects on resonator performance and cell property measurement, a new approach in microfluidic biosensing.

Findings

Hydrostatic compression reduces the mass detection limit of resonators.

Compression shifts mass distributions, aiding cell line differentiation.

Method enables measurement of cell compressibility for diagnostics.

Abstract

Microfluidics offer remarkable flexibility for in-flow analyte characterization and can even measure the mechanical properties of biological cells through the application of hydrodynamic forces. In this work, we present a new approach to enhance the performance of nanomechanical resonators featuring integrated microfluidic channels when they are used as cell sensors by means of applying hydrostatic compressions. For this purpose, we have studied analytically how this kind of compressions affects either the mechanical properties of the resonator as well as the analytes. We found that, depending on factors such as device geometry and material composition, the mass limit of detection of the resonator can be reduced while the buoyant mass of the particles is increased when a hydrostatic compression is applied, improving the performance of the sensor. Furthermore, we demonstrate that applying these hydrostatic compressions induces shifts in mass distributions among cell lines with similar physical properties, which not only potentially enhances the ability to differentiate between these lines, but also opens the door to measure the cell's compressibility, a biophysical parameter of interest with practical diagnostic applications.