Nowukno — 2 years ago(August 16, 2023 01:36 PM)

https://www.livescience.com/archaeology/vlad-the-impaler-may-have-cried-tears-of-blood-chemical-analysis-of-his-letters-finds
To learn more about the bloodthirsty warlord, researchers used a technique called mass spectrometry that involved carefully applying ethylene-vinyl acetate, a polymer, to the letters, then removing it. The ethylene acetate picked up proteins and smaller molecules called peptides leftover from when the count handled the papers centuries ago. This process revealed residue that contained 500 peptides, of which 100 were of human origin. These peptides were presumed to come from Vlad, rather than other people who may have handled the letters.
The biggest find was from a letter he penned in A.D. 1475 that carried three peptides found in proteins of the retina and tears. Based on the features of these peptides, they concluded that he likely suffered from hemolacria, a condition in which blood is present in tears.
Researchers aren't sure what exactly caused him to have this condition, but it could be linked to an eye injury or bacterial conjunctivitis, an infection of the eye's mucous membrane.