Fig. 3
From: Pembrolizumab microgravity crystallization experimentation
SONICC analyses: visible, UV two-photon excited fluorescence and second-harmonic generation images for the ground and flight experiments. Particles were confirmed to be proteinous based on positive UV. There are 22 trytophans in pembrolizumab and their crystals give a strong UV signal. The pembrolizumab crystals are chiral and therefore give a strong SHG signal. Although the shown images are at slightly different focal planes, all the observed visible particles were UV and SHG positive. The upper panel is a representative sample of bottle contents from a ground experiment by visible (×200), UV, and SHG imaging. The bottom panel: the visible, UV, and SHG image from a representative flight experiment.
