Microfluidic Viscometer for Tear Films and Other Biofluids

Abstract

A microfluidic viscometer platform is developed and validated for measuring microliter-volume liquid samples, such as human tear films. The microfluidic viscometer combines an optically clear acrylic chip with a hydrophobic surface coating together with a syringe pump to control the sample flow rate. Additional functionally supporting devices, including a camera and a differential pressure transducer, were used for analysis. It has been demonstrated that the microfluidic viscometer could measure the viscosities of both Newtonian and non-Newtonian liquid samples, and their relevant calculations are presented. The microfluidic viscometer has potential applications in measuring the rheological properties of biofluids for diagnostic applications.