A media dispenser or a culture media dispenser is a device for repeatedly delivering small fixed volumes of liquid such as a laboratory growth medium like molten agar or caustic or volatile solvents like toluene into a series of receptacles. It is often important that such dispensers operate without biological or chemical contamination, and so must be internally sealed from the environment and designed for easy cleaning and sterilization before use. At a minimum, a media dispenser consists of some kind of pump connected to a length of discharge tubing or a spout. Dispensers used in laboratories are also frequently connected to microcontrollers to regulate the speed and volume of the medium as it leaves the pump.
Syringe pump
Sterile media dispenser with electromagnetic inductive pump manufactured by Tritech Research
A bottle top media dispenser
A single syringe pump
A growth medium or culture medium is a solid, liquid, or semi-solid designed to support the growth of a population of microorganisms or cells via the process of cell proliferation or small plants like the moss Physcomitrella patens. Different types of media are used for growing different types of cells.
An agar plate – an example of a bacterial growth medium*: Specifically, it is a streak plate; the orange lines and dots are formed by bacterial colonies.
US Food and Drug Administration scientist tests for Salmonella
A culture of salmonella bacteria
Physcomitrella patens plants growing axenically on agar plates (Petri dish, 9 cm diameter)