Tag Archive for: Love-SAW sensors

Publication on AWSensors technology

Portable Surface Acoustic Wave device platform coupled with a paper-based capillary fluidics for real-time biosensing applications

Authors: Angelos Ntimtsas and Electra Gizeli

Journal: Chemical Society Sensors and Actuators A: Physical

Abstract: Surface acoustic wave (SAW) sensors have emerged as prominent real-time, label-free biosensors with diverse applications in immunoassays and nucleic acid detection. However, widespread adoption in diagnostics has been impeded by challenges such as miniaturization of instrumentation, microfluidics fabrication and high attenuation in liquid environments. In this study we address these limitations by presenting a portable platform capable of real-time monitoring of a SAW microarray chip comprising up to four sensing channels, combined with a novel paper-based capillary flow channel. For the fabrication of a portable, automated and versatile sensor platform, we integrated a microcontroller, RF components, and a micropump for flow control. Calibration procedures ensured accurate measurements for both amplitude and phase, with a low drift rate (0.72 mdB/h and 1.00 mdeg./h, respectively) and high resolution (2.10 mdB and 6.10 mdeg.), indicating stable operation with minimal interface electronics. The capillary flow channel, implemented by confining the fluid on the sensing surface using a nitrocellulose strip, facilitated laminar and continuous sample flow with minimum damping of the acoustic signal. The sensor system was evaluated with two SAW devices at 100 and 200 MHz using glycerol dilutions within the range of 1% and 70%, demonstrating real-time monitoring capabilities and linear correlations between amplitude and phase changes. To prove the biosensing and clinical validity of the SAW newly developed system, DNA adsorption on a poly(L-lysine)-graft-poly(ethylene glycol) (PLL-g-PEG) functionalized SAW-surface was demonstrated with a detection limit of 0.001 μg/mL. Our study demonstrates the feasibility of a portable SAW sensor system coupled with a low-cost and replaceable capillary flow channel for real-time monitoring and biomolecular detection.

The full article can be accessed here.

Publication on AWSensors technology

Surface Acoustic Wave Immunosensor for Detection of Botulinum Neurotoxin

Authors: Michał Grabka, Krzysztof Jasek and Zygfryd Witkiewicz

Journal: Sensors (2023)

 

Abstract

A Love-type acoustic wave sensor (AT-cut quartz substrate, SiO2 guiding layer) with a center frequency of approximately 120 MHz was used to detect a simulant of pathogenic botulinum neurotoxin type A—recombinant of BoNT-A light chain—in liquid samples. The sensor was prepared by immobilizing monoclonal antibodies specific for botulinum neurotoxin via a thiol monolayer deposited on a gold substrate. Studies have shown that the sensor enables selective analyte detection within a few minutes. In addition, the sensor can be used several times (regeneration of the sensor is possible using a low pH buffer). Nevertheless, the detectability of the analyte is relatively low compared to other analytical techniques that can be used for rapid detection of botulinum neurotoxin. The obtained results confirm the operation of the proposed sensor and give hope for further development of this label-free technique for detecting botulinum neurotoxin.

Surface Acoustic Wave (Love-SAW) immunosensor for detection of botulinum neurotoxin. Source: Sensors 2023, 23(18), 7688

You may read the full paper here.

QCMD workshop training

Hands-on Training Workshop on QCMD at IMBB-FORTH, Greece

AWSensors ran a successful hands-on training workshop at the Gizeli group at IMBB FORTH in Crete, Greece. Undergraduate students, graduate students, and postdocs were invited to attend the session and learned how to use our X1 QCMD instrument and Love-SAW devices. During the workshop, participants had the opportunity to understand how to effectively utilize these acoustic sensing technologies for their research. Building on their core expertise in molecular biology and biophysics, the Gizeli group is exploring biosensing applications in human, animal, and plant disease diagnostics as well as pathogen and environmental pollutant detection. The training helped researchers in the group exploit the unique advantages of AWSensors’ equipment, such as sensitivity, time resolution, flexibility, integrated flow control, and ease of use, for biosensor development.