Stool For Hanging Drop

Stool For Hanging Drop test checks for the presence of certain bacteria that have an organ for locomotion known as flagella. This method is the modified version of the wet mount method. It is the most commonly used examination method in microbiology to determine the motility (rate of movement) of Vibrio cholerae.

In this method, a drop of the specimen is put on a glass coverslip and encircled with petroleum jelly. After that, the coverslip and drop are inverted over the well of a depression slide. The drop dangles from the coverslip, and the petroleum jelly forms a seal to keep it from evaporating. This preparation provides a clear image of bacteria moving across the microscopic field and showing the true signs of motility.