This image is an extension of the study referenced in the image "Yi Jian Mei". Different amino acids were added to tripeptide structures, and different fluorescence color was emitted. When the tripeptides tried to crystallize into a solution, they had very distinct morphology and fluorescence. The image is an example of this, highlighting the process as it happens to melatonin nanoparticles.

A. Lampel, S.A. McPhee, S. Kassem, D. Sementa, T. Massarano, J. M. Aramini, Y. He, and R. V. Ulijn, Melanin-Inspired Chromophoric Microparticles Composed of Polymeric Peptide Pigments, Angew Chem Int Ed Engl, 2021, 60, 7564-7569.