Amylmetacresol/2,4-dichlorobenzyl alcohol, hexylresorcinol, or carrageenan lozenges as active treatments for sore throat

Morokutti-Kurz, Martina; Graf, Christine; Prieschl-Grassauer, Eva

The assay was performed as described elsewhere 13 with small adaptations to account for the high viscosity of the lozenges solutions. In short, the virus was preincubated with a semilogarithmic dilution series of lozenges or control solutions for 30 minutes at RT (prophylactic treatment) before it was added to a monolayer of MDCK cells for infection. After an infection period of 45 minutes at RT the inoculum was removed; cells were overlaid with semiliquid carboxymethylcellulose medium and then cultured at 37°C, hereby maintaining the same concentrations of active agent as in the prophylactic treatment. Staining was performed on fixed cells using an antibody directed against the influenza virus A nucleoprotein with a horse radish peroxidase labeled detection antibody and TMB as substrate. To enable direct comparison of the antiviral effectiveness of the lozenges, the ID 50 value of each sample was calculated for a sigmoidal dose-response model with XLfit Excel add-in version 5.3.1. From this value, corresponding iota-carrageenan concentrations were calculated for lozenge #1.