doser

A doser is a device or mechanism designed to dispense precise amounts of a substance, typically liquids or powders, for controlled addition in laboratory, industrial, culinary, and consumer applications. Dosing can be performed manually or automatically, depending on the required accuracy and timing.

Manual dosers include tools such as syringes, pipettes, measuring spoons, and droppers that rely on the operator for volume control. Automatic dosers rely on mechanical or electronic systems to deliver a fixed quantity or a calibrated flow. Common automatic mechanisms include peristaltic pumps, diaphragm pumps, piston or syringe-based dispensers, and gravimetric or mass-based dosing systems that use weight to determine the dose.

Volumetric dosing delivers a specific volume per actuation or cycle, while gravimetric dosing uses a scale or load cell to ensure the delivered mass matches a target value. Calibration, maintenance, and cleaning are essential to maintain accuracy and prevent cross-contamination, especially in pharmaceutical, food, and healthcare contexts.

Applications span multiple fields. In laboratories, dosers add reagents with precision for experiments and formulations. In pharmaceutical manufacturing, precise dosing supports correct drug formulations. In water treatment and chemical processing, dosers regulate additives such as disinfectants and corrosion inhibitors. In agriculture and hydroponics, dosing pumps deliver nutrients; in aquariums, dosers automate dosing of minerals and CO2. In the coffee industry, dosing devices may measure ground coffee into the portafilter.

Etymology derives from dose and the agent noun suffix -er. Variants include dosing pumps, dosing systems, and gravimetric dosing units, each chosen to meet specific accuracy, viscosity, and automation requirements.