Publication detail
Mass Spectrometry of Heavy Analytes and Large Biological Aggregates by Monitoring Changes in the Quality Factor of Nanomechanical Resonators in Air
STACHIV, I. GAN, L. KUO, CH.Y. ŠITTNER, P. ŠEVEČEK, O.
English title
Mass Spectrometry of Heavy Analytes and Large Biological Aggregates by Monitoring Changes in the Quality Factor of Nanomechanical Resonators in Air
Type
journal article in Web of Science
Language
en
Original abstract
Nanomechanical resonators are routinely used for identification of various analytes like biological and chemical molecules, viruses or bacteria cells from the frequency response. This identification based on the multimode frequency shift measurement is limited to analyte of mass that is much lighter than the resonator mass; hence the analyte can be modeled as a point particle and, as such, its stiffness and nontrivial binding effects like surface stress can be neglected. For heavy analytes (> MDa) this identification, however, leads to incorrectly estimated masses. Here, by using a well-known frequency response of the nanomechanical resonator in air, we show that the heavy analyte can be identified without a need for highly challenging analysis of the analyte position, stiffness and/or binding effects just by monitoring changes in quality factor of a single harmonic frequency. Theory with a detailed procedure of mass extraction from quality factor is developed. In air, the quality factor depends on analyte mass and known air damping, while impact of the intrinsic dissipation is negligibly small. We find that the highest mass sensitivity (for considered resonator dimensions ~zg) can be achieved for rarely measured lateral mode, whereas the commonly detected flexural mode yields the lowest sensitivity. Validity of proposed procedure is confirmed by extracting mass of heavy analytes (GDa) made of protein and E. coli bacteria cells, and the ragweed pollen nanoparticle adsorbed on surface of the nanomechanical resonator(s) in air, of which the required changes in quality factor were previously experimentally measured, and by using numerical simulations. Our results open a doorway for rapid detection of viruses and bacteria cells using standard nanomechanical mass sensors.
English abstract
Nanomechanical resonators are routinely used for identification of various analytes like biological and chemical molecules, viruses or bacteria cells from the frequency response. This identification based on the multimode frequency shift measurement is limited to analyte of mass that is much lighter than the resonator mass; hence the analyte can be modeled as a point particle and, as such, its stiffness and nontrivial binding effects like surface stress can be neglected. For heavy analytes (> MDa) this identification, however, leads to incorrectly estimated masses. Here, by using a well-known frequency response of the nanomechanical resonator in air, we show that the heavy analyte can be identified without a need for highly challenging analysis of the analyte position, stiffness and/or binding effects just by monitoring changes in quality factor of a single harmonic frequency. Theory with a detailed procedure of mass extraction from quality factor is developed. In air, the quality factor depends on analyte mass and known air damping, while impact of the intrinsic dissipation is negligibly small. We find that the highest mass sensitivity (for considered resonator dimensions ~zg) can be achieved for rarely measured lateral mode, whereas the commonly detected flexural mode yields the lowest sensitivity. Validity of proposed procedure is confirmed by extracting mass of heavy analytes (GDa) made of protein and E. coli bacteria cells, and the ragweed pollen nanoparticle adsorbed on surface of the nanomechanical resonator(s) in air, of which the required changes in quality factor were previously experimentally measured, and by using numerical simulations. Our results open a doorway for rapid detection of viruses and bacteria cells using standard nanomechanical mass sensors.
Keywords in English
mass spectrometry; mass sensor; NEMS; nanomechanical resonator; nanomechanics
Released
19.06.2020
Publisher
ACS Publications
Location
Spojené státy americké
ISSN
2379-3694
Volume
5
Number
7
Pages from–to
2128–2135
Pages count
8
BIBTEX
@article{BUT164671,
author="Oldřich {Ševeček},
title="Mass Spectrometry of Heavy Analytes and Large Biological Aggregates by Monitoring Changes in the Quality Factor of Nanomechanical Resonators in Air",
year="2020",
volume="5",
number="7",
month="June",
pages="2128--2135",
publisher="ACS Publications",
address="Spojené státy americké",
issn="2379-3694"
}