Jump to main content
Jump to site search
Access to RSC content Close the message box

Continue to access RSC content when you are not at your institution. Follow our step-by-step guide.

Issue 5, 2019
Previous Article Next Article

A liquid metal based capacitive soft pressure microsensor

Author affiliations


A liquid-metal based capacitive soft pressure microsensor is proposed in this work for measuring pressure in microchannels. To measure the pressure of the target microchannel, a short detection channel is fabricated and connected to the target microchannel. Because the detection channel has only one outlet at the end which is connected to the target microchannel, the fluid in the detection channel will stay still during the measurement and the pressure remains constant inside the detection channel. A segment of reference fluid which is immiscible with the working fluid is sealed inside the detection channel. Because the chip material is soft, the pressure change will lead to the movement of the interface between the reference fluid and working fluid inside the detection channel. A pair of liquid metal electrodes are fabricated on both sides of the detection channel. By measuring the capacitance between these two liquid metal electrodes, the movement of the interface can be detected, and thus the pressure change can be detected as well. To minimize the influence from the environment, two liquid metal shield layers are placed on the top and the bottom of the microchannel layer separately. The microsensor was first tested in a microfluidic system and then utilized to measure the blood pressure of rabbit carotid artery in vivo. The experimental results showed excellent stability and linear correlation between capacitance and the value of fluid pressure. The pressure sensor can achieve a resolution of 7.5 mmHg within a pressure range of 20–300 mmHg. This work provides a promising approach to develop an implantable blood or intraocular pressure-monitoring device for clinical use.

Graphical abstract: A liquid metal based capacitive soft pressure microsensor

Back to tab navigation

Article information

12 Dec 2018
16 Jan 2019
First published
18 Jan 2019

Lab Chip, 2019,19, 807-814
Article type

A liquid metal based capacitive soft pressure microsensor

X. Zhou, R. Zhang, L. Li, L. Zhang, B. Liu, Z. Deng, L. Wang and L. Gui, Lab Chip, 2019, 19, 807
DOI: 10.1039/C8LC01357H

Social activity

Search articles by author