The Concept of a Spatial Affinity Lock-in Amplifier

11. January 2021

Frutiger, A., Fattinger, C. & Vörös, J. Sensors 21, (2021)

Focal molography – a new method for Biomolecular Interaction Analysis (BIA).
The paper introduces and demonstrated the concept of the “spatial affinity lock-in” as a novel design principle to overcome the drawbacks of established BIA methods.The spatial affinity lock-in is analogous to the time-domain lock-in. Instead of a time-domain signal, it modulates the binding signal at a high spatial frequency to separate it from the low spatial frequency environmental noise in Fourier space. Focal molography applies this fundamental detection principle to BIA. Combined with the right surface chemistry and recognition elements on the sensor surface focal molography enables robust, sensitive and fundamentally new BIA assays such as the direct and label-free monitoring of biomolecular interaction on the cell membrane.
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