Pulled microcapillary tube resonators with electrical readout for mass sensing applications.

ABSTRACT: This paper reports a microfabrication-free approach to make hollow channel mass sensors by pulling a glass capillary and suspending it on top of a machined jig. A part of the pulled section makes simple contact with an actuation node and a quartz tuning fork (QTF) which acts as a sensing node. The two nodes define a pulled micro capillary tube resonator (P?TR) simply supported at two contacts. While a piezo actuator beneath the actuation node excites the P?TR, the QTF senses the resonance frequency of the P?TR. The proposed concept was validated by electrical and optical measurements of resonant spectra of P?TR. Then, different liquid samples including water, ethanol, glycerol, and their binary mixtures were introduced into the P?TR and the resonance frequency of the P?TR was measured as a function of liquid density. Density responsivity of -3,088?Hz-g-1?cm3 obtained is comparable to those of microfabricated hollow resonators. With a micro droplet generation chip configured in series with the P?TR, size distribution of oil droplets suspended in water was successfully measured with the radius resolution of 31?nm at the average droplet radius, 28.47??m. Overall, typical off-the-shelf parts simply constitute a resonant mass sensing system along with a convenient electrical readout.

SUBMITTER: Lee D 

PROVIDER: S-EPMC5046181 | biostudies-literature | 2016 Oct

REPOSITORIES: biostudies-literature