PuSH - Publikationsserver des Helmholtz Zentrums München

De Pastina, A.* ; Padovani, F. ; Brunetti, G.* ; Rotella, C.* ; Niosi, F.* ; Usov, V.* ; Hegner, M.*

Multimodal real-time frequency tracking of cantilever arrays in liquid environment for biodetection: Comprehensive setup and performance analysis.

Rev. Sci. Instruments 92:065001 (2021)
Verlagsversion DOI PMC
Open Access Gold (Paid Option)
Creative Commons Lizenzvertrag
We present a nanomechanical platform for real-time quantitative label-free detection of target biomolecules in a liquid environment with mass sensitivity down to few pg. Newly fabricated arrays of up to 18 cantilevers are integrated in a micromachined fluidic chamber, connected to software-controlled fluidic pumps for automated sample injections. We discuss two functionalization approaches to independently sensitize the interface of different cantilevers. A custom piezo-stack actuator and optical readout system enable the measurement of resonance frequencies up to 2 MHz. We implement a new measurement strategy based on a phase-locked loop (PLL), built via in-house developed software. The PLL allows us to track, within the same experiment, the evolution of resonance frequency over time of up to four modes for all the cantilevers in the array. With respect to the previous measurement technique, based on standard frequency sweep, the PLL enhances the estimated detection limit of the device by a factor of 7 (down to 2 pg in 5 min integration time) and the time resolution by more than threefold (below 15 s), being on par with commercial gold-standard techniques. The detection limit and noise of the new setup are investigated via Allan deviation and standard deviation analysis, considering different resonance modes and interface chemistries. As a proof-of-concept, we show the immobilization and label-free in situ detection of live bacterial cells (E. coli), demonstrating qualitative and quantitative agreement in the mechanical response of three different resonance modes.
Altmetric
Weitere Metriken?
Zusatzinfos bearbeiten [➜Einloggen]
Publikationstyp Artikel: Journalartikel
Dokumenttyp Wissenschaftlicher Artikel
Korrespondenzautor
Schlagwörter Growth; Biosensors; Sensors; Assay
ISSN (print) / ISBN 0034-6748
e-ISSN 1089-7623
Quellenangaben Band: 92, Heft: 6, Seiten: , Artikelnummer: 065001 Supplement: ,
Verlag American Institute of Physics (AIP)
Verlagsort 1305 Walt Whitman Rd, Ste 300, Melville, Ny 11747-4501 Usa
Nichtpatentliteratur Publikationen
Begutachtungsstatus Peer reviewed