·         A micromanipulator is a device which is used to physically interact with a sample under a microscope
·         It may typically consist of an input joystick , a mechanism for reducing the range of movement and an output section with the means of holding a micro tool to hold, inject, cut or otherwise manipulate the object as required
·         Micromanipulators are usually used in conjunction with microscope.
·         It is the method used in the isolation of pure culture technique.


·         Micromanipulator have been built, which permit one to pick out a single cell from a mixed culture.
·         This instrument is used in conjunction with a microscope to pick a single cell (particularly bacterial cell) from a hanging drop preparation.
·         The micromanipulator have a micrometer adjustments by means of which its micropipette can be move right and left, forward and backward, and up and down.
·         A series of hanging drop of a diluted culture are placed on a special sterile cover slip by a micropipette.  
·         Now a hanging drop is searched, which contains only a single  microorganism cell
·         This cell is drawn into the micropipette by gentle suction and then transferred to a large drop of sterile medium on another sterile coverslip.
·         When the number of cell increases in that drop as a result of multiplication, the drop is transferred to a culture tube having suitable medium.
·         This yield a pure culture of the required microorganism.


·         The advantage of this method are that can be reasonably sure that the cultures come from a single cell and one can obtain strains within the species.


·         Equipment is expensive.
·         Its manipulation is very tedious.
·         It required a skilled operator.


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