Micromanipulator
Encyclopedia
A micromanipulator is a device which is used to physically interact with a sample under a microscope, where a level of precision of movement is necessary that cannot be achieved by the unaided human hand. 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 microtool to hold, inject, cut or otherwise manipulate the object as required. The mechanism for reducing the movement usually requires the movement to be free of backlash
. This is achieved by the use of kinematic constraints to allow each part of the mechanism to move only in one or more chosen degrees of freedom, which achieves a high precision and repeatability of movement, usually at the expense of some absolute accuracy.
Movement reduction can be performed by mechanical levers, hydraulically using pistons of different diameters connected by tubing containing non-compressible fluid, electronically using stepper motors or linear actuators, or combinations of techniques in one instrument. Mechanisms with different ranges of movement or variable reduction ratio may be incorporated in one instrument to allow coarse and fine positioning.
Micromanipulators are usually used in conjunction with microscopes. Depending on the application, one or more micromanipulators may be fitted to a microscope stage or rigidly mounted to a bench next to a microscope. A typical application of micromanipulation is human intracytoplasmic sperm injection
. Here, a spermatozoon measuring some 3 to 5 micrometres across is injected into an oocyte of approximately 100 micrometres in diameter, under the direct manual control of an embryologist. A disposable glass micropipette is fitted to a toolholder mounted on the output of the manipulator.
Micromanipulators are also used in applications such as microelectronics to position test probes onto small to medium scale integrated circuits and hybrid devices, and patch clamp
experiments in biological research.
Backlash (engineering)
In mechanical engineering, backlash, sometimes called lash or play, is clearance between mating components, sometimes described as the amount of lost motion due to clearance or slackness when movement is reversed and contact is re-established...
. This is achieved by the use of kinematic constraints to allow each part of the mechanism to move only in one or more chosen degrees of freedom, which achieves a high precision and repeatability of movement, usually at the expense of some absolute accuracy.
Movement reduction can be performed by mechanical levers, hydraulically using pistons of different diameters connected by tubing containing non-compressible fluid, electronically using stepper motors or linear actuators, or combinations of techniques in one instrument. Mechanisms with different ranges of movement or variable reduction ratio may be incorporated in one instrument to allow coarse and fine positioning.
Micromanipulators are usually used in conjunction with microscopes. Depending on the application, one or more micromanipulators may be fitted to a microscope stage or rigidly mounted to a bench next to a microscope. A typical application of micromanipulation is human intracytoplasmic sperm injection
Intracytoplasmic sperm injection
Intracytoplasmic sperm injection is an in vitro fertilization procedure in which a single sperm is injected directly into an egg.-Indications:...
. Here, a spermatozoon measuring some 3 to 5 micrometres across is injected into an oocyte of approximately 100 micrometres in diameter, under the direct manual control of an embryologist. A disposable glass micropipette is fitted to a toolholder mounted on the output of the manipulator.
Micromanipulators are also used in applications such as microelectronics to position test probes onto small to medium scale integrated circuits and hybrid devices, and patch clamp
Patch clamp
The patch clamp technique is a laboratory technique in electrophysiology that allows the study of single or multiple ion channels in cells. The technique can be applied to a wide variety of cells, but is especially useful in the study of excitable cells such as neurons, cardiomyocytes, muscle...
experiments in biological research.