Comparison of the Physical Properties and Effectiveness of Medical Swabs for Sampling Biomaterials

The COVID-19 pandemic has induced a sharp rise in demand for consumables for laboratory diagnosis and, in particular, for swabs for sampling biomaterials. Test quality depends strongly on swab quality. The aim of this work was to run experimental studies to evaluate the physical and operational properties of fiber-type medical swabs. This study compared swabs from leading manufacturers traditionally regarded as the quality standard on the Russian market in the premium sector: Copan Diagnostics (Italy), Puritan Medical Products (PMP) (USA), and PharmMedPolis (PhMP) (Russia). The following properties were studied: absorption, zeta potential, and surface morphology (by scanning electron microscopy). The techniques for biomaterial collection and release were also considered. Experiments using Streptomyces pneumoniae cultures as an example showed that the Copan Diagnostics swab had a recovery rate (RR) of 78.3%, compared with 84.15% for the Puritan Medical Products swab, 87.49% for the PhMP swab, and 93.72% for the HydraFlock® swab. The HydraFlock® swab was found to be especially effective due to its high ability to absorb water and protein and its high bacterial recovery rate. The second best results were for the PharmMedPolis® swab, followed by the Copan swab and the nylon swab from Puritan Medical Products.