Visual evaluation of binding to mucosal cells of a medical device against the common cold

The objective of this study was to investigate the possibility of visualizing the ability of hydroxypropylmethylcellulose (HPMC) and a nasal spray (First Defense), in which the bioadhesive is HPMC, to bind to human mucosal cells using inorganic (black carbon particles and Congo red dye) and organic markers (Escherichia coli). A significant reduction in the bacterial adhesiveness has been observed. Our findings indicate the possibility of counteracting the lock-and-key mechanism of microorganism adhesion using the bioadhesive properties of polymers, such as HPMC, in First Defense to prevent a possible contact between adhesins and complementary receptors.