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Recently, a bio-inspired, synthetic membrane-based hair cell sensor was fabricated and characterized. This sensor
generates current in response to mechanical stimuli, such as airflow or free vibration, which perturb the sensor’s hair.
Vibration transferred from the hair to a lipid membrane (lipid bilayer) causes a voltage-dependent time rate of change in
electrical capacitance of the membrane, which produces measurable current. Studies to date have been performed on
systems containing only two droplets and a single bilayer, even though an array of multiple bilayers can be formed with
more than 2 droplets. Thus, it is yet to be determined how multiple lipid bilayers affect the sensing response of a
membrane-based hair cell sensor. In this work, we assemble serial droplet arrays with more than 1 bilayer to
experimentally study the current generated by each membrane in response to perturbation of a single hair element. Two
serial array configurations are studied: The first consists of a serial array of 3 bilayers formed using 4 droplets with the
hair positioned in an end droplet. The second configuration consists of 3 droplets and 2 bilayers in series with the hair
positioned in the central droplet. In serial arrays of up to four droplets, we observe that mechanotransduction of the
hair’s motion into a capacitive current occurs at every membrane, with bilayers positioned adjacent to the droplet
containing the hair generating the largest sensing current. The measured currents suggest the total current generated by
all bilayers in a 4-droplet, 3-bilaye array is greater than the current produced by a single-membrane sensor and similar in
magnitude to the sum of currents output by 3, single-bilayer sensors operated independently. Moreover, we learned that
bilayers positioned on the same side of the hair produce sensing currents that are in-phase, whereas bilayers positioned
on opposite sides of the droplet containing the hair generate out-of-phase responses.
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