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Highlights • Analytical formula-based method for resonance frequency measurement. • Simple quartz crystal microbalance (QCM) using a fixed frequency drive. • Ultrafast QCM with sub-millisecond time resolution and low noise. • Validated against impedance analysis method for mass and viscous loading. Abstract A new method for determination of resonance frequency and dissipation of a mechanical oscillator is presented. Analytical expressions derived using the Butterworth-Van Dyke equivalent electrical circuit allow the determination of resonance frequency and dissipation directly from each impedance datapoint acquired at a fixed amplitude and frequency of drive, with no need for numerical fitting or measurement dead time unlike the conventional impedance or ring-down analysis methods. This enables an ultrahigh time resolution and superior noise performance with relatively simple instrumentation. Quantitative validations were carried out successfully against the impedance analysis method for inertial and viscous loading experiments on a 14.3 MHz quartz crystal resonator (QCR). Resonance frequency shifts associated with the transient processes of quick needle touches on a thiol self-assembled-monolayer functionalised QCR in liquid were measured with a time resolution of 112 μs, which is nearly two orders of magnitude better than the fastest reported quartz crystal microbalance. This simple and fast fixed frequency drive (FFD) based method for determination of resonance frequency and dissipation is potentially more easily multiplexable and implementable on a single silicon chip delivering economies of scale. [ABSTRACT FROM AUTHOR]

Despite advancements in analytical technologies, their complexity and cost have largely restricted their application in scalable online or multiplexed measurements. Here we report a quartz crystal resonator (QCR)-based method for detection of macromolecules that allows immensely simpler and faster measurements by employing for the first time a fixed frequency drive (FFD) and analytical expressions of acoustic parameters. Using human immunoglobulin E (hIgE) as an exemplar macromolecule and an anti-hIgE aptamer functionalised on a QCR, quantitative accuracy was benchmarked against the traditional impedance analysis method. The ability of FFD to capture data over longer observation periods at significantly higher acquisition rates at a fixed amplitude showed improvement in the QCR's sensitivity and specificity of transduction. The foundations for low-cost and low-power online integration and large-scale multiplexability are also discussed. • Analytical expressions for acoustic shift measurement. • Simpler quartz crystal microbalance (QCM) using a fixed frequency drive. • Ultrafast QCM with sub-millisecond time resolution. • Ultralow baseline noise, higher transduction sensitivity and specificity. • Promising for online integration and large-scale multiplexability. [ABSTRACT FROM AUTHOR]