Some are more equal--a comparative study on swab uptake and release of bacterial suspensions

Swabs are widely used to collect samples for microbiological analyses from various clinical settings. They vary by material, size, and structure of the tip. This study investigates the uptake and release capacities for liquid and bacteria. Five swabs were analyzed for their uptake and release capacities of Staphylococcus aureus and Staphylococcus epidermidis suspensions. Two approaches were investigated providing volume-restricted and unrestricted amounts of bacterial suspensions to mimic various clinical situations. Volume and bacterial uptake and release were measured in milligrams and by counting colony forming units (CFU), respectively. Volume uptake and release in the unrestricted setting varied highly significant between 239.6 mg and 88.7 mg (p