Fig. 1.

Infectivity of freeze-dried HCoV-NL63. TCID₅₀ as a measure of infectivity of the lyophilized virus was assessed 6 days post infection. All assays were performed in triplicate in at least three independent experiments and average values with standard errors (error bars) are presented. Presented data is shown as % of TCID₅₀ in the relation to PBS control. All formulation names are described in Table 1.