Measuring low flow rates of liquids, especially in miniature chemical analysis systems or in medicine, using sensor to record change in chemical composition of the liquid

摘要

A sensor (16) monitors the change in chemical composition of the liquid (12) carried out at another location using an actuator (14). A method for measuring the flow of a liquid uses an actuator to alter the chemical composition of this liquid and using a sensor at another location to record this change. Independent claims are also included for (a) the measuring device, including a control unit (18) for operating the actuator, reading the sensor and processing the sensor data, and (b) a method for making this device, by etching a channel in one or two essentially flat substrates preferably comprising silicon, glass or polymer, depositing ion-sensitive field effect transistors (ISFET's) and/or thin patterned metal layers on the substrate(s), and joining the two substrates together.