Inoculating loop or wire loop is a general purpose piece of instrument that allows microbiologist to transfer microorganisms in an aseptic manner from one place to another. Colonies of microbes growing on culture media plates of slants can be transferred onto glass slides or fresh culture medium for further studies, and this is only made possible with the aid of a wire loop (Figure 1).
Several types of wire loop exist for the transfer of microorganisms in the microbiology laboratory. Wire loop can also be used to streak microbial cultures or experimental samples onto the surface of solid culture media plates. They are also used to inoculate broth or liquid cultures with experimental samples or microbes.
The main components of the wire loop include nichrome wire and the wooden handle. Apart from the traditional nichrome wire loop used for various microbiological investigations, disposable plastic wire loops which can only be used once also exist.
The nichrome wire loop is heat-stable and can be used over a long period of time. Nichrome wire loops should be kept dry and away from moist environment to prevent corrosion or rusting.
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