Efficacy of phage K-MPs against UAMS-1 in presence of CF sputum supernatant and viscous artificial sputum. A, Normalized optical density of UAMS-1 suspension in a mixture of LB and sputum supernatant was measured at 630 nm over a period of 10 hours in presence of phage K-MPs or unloaded MPs. B, Enumeration of bacterial counts post treatment of phage K-MPs or MPs with UAMS-1 grown in artificial CF sputum. A mixture of 90 μL bacterial suspension (1×107 CFU/mL) in artificial CF sputum medium and 10 μL LB was treated with MPs or phage K-MPs (2 mg/mL) for 24 hours. The suspensions were serially diluted, plated on agar plates, and incubated at 37 °C, followed by enumeration of bacterial colonies after 16–20 hours. Dashed line represents limit of detection. Two way ANOVA with Sidak test for multiple comparison. ****P < 0.0001 via unpaired two-tailed t test, N = 3.