An inoculation loop (also called a smear loop, inoculation wand or microstreaker) is a simple tool used mainly by microbiologists to pick up and transfer a small sample of microorganisms called inoculum from a microbial culture, e.g. for streaking on a culture plate.
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It was originally made of twisted metal wire (such as platinum, tungsten or nichrome), but disposable molded plastic versions are now common.
An early report of the use of an inoculation loop as an analytical tool was by O'Sullivan et al.[3] 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.