An inoculation loop (also called a smear loop, inoculation wand or microstreaker) is a simple tool used mainly by

microbiologist A microbiologist (from Greek ) is a scientist who studies microscopic life forms and processes. This includes study of the growth, interactions and characteristics of microscopic organisms such as bacteria, algae, fungi, and some types of par ...

s to pick up and transfer a small sample of microorganisms called inoculum from a microbial culture, e.g. for

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on a culture plate.Ronald Westphal (1988):
Microbiological Techniques in School
', page 34. Document No. 28 in the series ''Science and Technology Education''. This process is called

inoculation Inoculation is the act of implanting a pathogen or other microbe or virus into a person or other organism. It is a method of artificially inducing immunity against various infectious diseases. The term "inoculation" is also used more generally ...

. The tool consists of a thin handle with a loop about 5 mm wide or smaller at the end. It was originally made of twisted

metal A metal () is a material that, when polished or fractured, shows a lustrous appearance, and conducts electrical resistivity and conductivity, electricity and thermal conductivity, heat relatively well. These properties are all associated wit ...

wire (such as

platinum Platinum is a chemical element; it has Symbol (chemistry), symbol Pt and atomic number 78. It is a density, dense, malleable, ductility, ductile, highly unreactive, precious metal, precious, silverish-white transition metal. Its name origina ...

tungsten Tungsten (also called wolfram) is a chemical element; it has symbol W and atomic number 74. It is a metal found naturally on Earth almost exclusively in compounds with other elements. It was identified as a distinct element in 1781 and first ...

or nichrome), but disposable molded

plastic Plastics are a wide range of synthetic polymers, synthetic or Semisynthesis, semisynthetic materials composed primarily of Polymer, polymers. Their defining characteristic, Plasticity (physics), plasticity, allows them to be Injection moulding ...

versions are now common. The size of the loop determines the volume of liquid an inoculation loop can transfer. An early report of the use of an inoculation loop as an analytical tool was by O'Sullivan ''et al.'' in a 1960 published protocol developed to improve methods for culturing urine samples. A 3mm diameter loop was used to deliver a consistent volume of urine for analysis. Loops can now be purchased to transfer volumes ranging from 1-10 microliters, though pipettes have replaced inoculation loops as more reliable tools to deliver small volumes of liquid.

References

Microbiology equipment {{Microbiology-stub

See also

References