An integrated microfluidic system for interstitial fluid transdermal extraction

Abstract

We present a new microfluidic system for transdermal interstitial fluid (ISF) extraction, collection, and volumetric measurement towards the application of continuous glucose monitoring. This device consists of a venturi tube, a volume sensor, pneumatic valves, and microchannels. Under the management of pneumatic valves, demonstration of the defined volume normal saline injection, ISF extraction, collection and volumetric measurement functions of the system is presented using the stable vacuum generated by the integrated venturi structure. The stability of defined volume normal saline injection is tested, and the coefficient of variation for 20 tests is 0.0041. A simulating test of ISF collection and volumetric measurement is done with the system, and the measurement results correlate well (R 2 =0.9992) with the values measured by micro syringe.

Design, fabrication and testing of a micro-Venturi tube for fluid manipulation in a microfluidic system

“…The optimized Venturi structure design was integrated into a microfluidic system for interstitial fluid transdermal extraction [12,13]. The 95 kPa vacuum force generated from the Venturi tube has been proven to successfully extract 'ISF analogue' through ultrasound pretreated pig skin and manipulate fluid transport in the microfluidic system.…”

A microfluidic system with volume sensor and dielectric glucose sensor for continuous glucose monitoring

“…The detailed working principle of the volume sensor was discussed previously [5]. Briefly, utilizing the conductivity of the electrolytic fluid (e.g.…”