Suspended Nanochannel Resonator Arrays with Piezoresistive Sensors for High-Throughput Weighing of Nanoparticles in Solution

Abstract

As the use of nanoparticles is expanding in many industrial sectors, pharmaceuticals, cosmetics among others, flow-through characterization techniques are often required for in-line metrology. Among the parameters of interest, the concentration and mass of nanoparticles can be informative for yield, aggregates formation or even compliance with regulation. The Suspended Nanochannel Resonator (SNR) can offer mass resolution down to the attogram scale precision in a flow-through format. However, since the readout has been based on the optical lever, operating more than a single resonator at a time has been challenging. Here we present a new architecture of SNR devices with piezoresistive sensors that allows simultaneous readout from multiple resonators. To enable this architecture, we push the limits of nanofabrication to create implanted piezoresistors of nanoscale thickness (∼100 nm) and implement an algorithm for designing SNRs with dimensions optimized for maintaining attogram scale precision. Using 8-in. processing technology, we fabricate parallel array SNR devices which contain ten resonators. While maintaining a precision similar to that of the optical lever, we demonstrate a throughput of 40 000 particles per houran order of magnitude improvement over a single device with an analogous flow rate. Finally, we show the capability of the SNR array device for measuring polydisperse solutions of gold particles ranging from 20 to 80 nm in diameter. We envision that SNR array devices will open up new possibilities for nanoscale metrology by measuring not only synthetic but also biological nanoparticles such as exosomes and viruses.

Reaching silicon-based NEMS performances with 3D printed nanomechanical resonators

“…In order to conduct as much as possible a comprehensive study, we analyzed more than 40 devices spanning over 16 orders of magnitude of device masses, divided into four different categories (detail of the analysis method and data references are reported in the Supplementary Information). Three categories are somehow related to standard lithographic technology: bottom-up NEMS (graphene, nanotube, and nanowires devices) 32 – 40 , top-down NEMS 4 , 41 – 52 , and MEMS resonators 53 – 57 . The fourth is represented by devices fabricated with the alternative techniques described previously 12 – 21 .…”

Potential of on‐chip analysis and engineering techniques for extracellular vesicle bioproduction for therapeutics

“…The diameter of EV can be deduced assuming a spherical shape and a constant exosome density of 1.16 g/ml throughout the populations, with a limit of diameter detection of 39 nm. In order to increase the throughput of the devices up to 40,000 particles per hour, Gagino et al 81 designed an architecture of parallel array SNR devices with piezoresistive sensors of 100 nm thickness that allows simultaneous readout from F I G U R E 5 Detection and analysis on chip of extracellular vesicles (EVs). (A) Label-free detection of exosomes with nanoplasmonic-exosome sensors (nPLEX) sensor, including a schematic descripting of the vesiculation principle of cancer cells through fusion with multi-vesicular body (MVB), finite difference time-domain simulation (heat scale) revealing enhanced detection spots at edges overlapping with vesicles sizes.…”

Inertial and viscous flywheel sensing of nanoparticles

“…1a ). We experimentally realize this motion using cantilevers in the form of suspended micro- and nanochannel resonators (SMRs/SNRs) 15 , 16 . The cantilevers vibrate in their second resonant flexural mode, where local rotation, without displacement, occurs at the vibrational nodes.…”