▎ 摘　　要

In fluid rheological studies, viscosity measurement is one of the most significant phenomena leveraged in a variety of studies. Viscometers are broadly employed in a wide range of sensing and monitoring applications, such as biochemical diagnostics and numerous adulteration detections. Therefore, it is pertinent to develop a miniaturized, automated, and cost-effective device that can measure the fluid viscosity from small samples. In this work, for fluid viscosity measurements, a new low-cost automated electro-microfluidic viscometer (EMV) has been fabricated on a hydrophilic laser-induced graphene (LIG) platform with integrated electronics to monitor viscosity from a small sample of fluid of 1.5 mu L. The principle of operation of the fabricated device is based on the modified Hagen-Poiseuille equation, which imitates the Ostwald viscometer. Under laminar flow, the proposed standalone and portable device automatically evaluates the travel time of fluid with high accuracy. This travel time was used to obtain viscosity accurately of various fluids, such as water, milk, and acetic acid, with a minimum error of up to +/- 1.08%. Overall, the device provides a pathway for a convenient, robust, and plug-and-play platform for different applications, including various adulteration monitoring and biosensing.