Optimization of SRFDS using a swab samples

To operate the SRFDS using a swab sample, a swab was first placed in 500 µL of lysis buffer (25 mM HEPES, 200 mM NaCl, 50 mM MgCl₂, and 0.1 % v/v NP-40; pH 7.5), and swirled at least 10 times and left still for 10 s.

To operate the diagnostic test, 10 μL of bioconjugates were applied to the conjugate pad. After covering the strip with the strip cover, 75 mL of sample, followed by 50 μL of lysis buffer, was introduced into the predefined hole in the strip cover. The strip was kept in the dark for 15 min and fluorescent intensities were measured using the smartphone detector.