Finding Out Egyptian Gods’ Secret Using Analytical Chemistry: Biomedical Properties of Egyptian Black Makeup Revealed by Amperometry at Single Cells

摘要

Lead-based compounds were used during antiquity as bothnpigments and medicines in the formulation of makeup materi-nals. Chemical analysis of cosmetics samples found in Egyptiansntombs and the reconstitution of ancient recipes as reported bynGreco-Roman authors have shown that two non-natural leadnchlorides (laurionite Pb(OH)Cl and phosgenite Pb2Cl2CO3)nwere purposely synthesized and were used as fine powdersnin makeup and eye lotions. According to ancient Egyptiannmanuscripts, these were essential remedies for treating eyenillness and skin ailments. This conclusion seems amazingnbecause today we focus only on the well-recognized toxicitynof lead salts. Here, using ultramicroelectrodes, we obtainnnew insights into the biochemical interactions betweennlead(II) ions and cells, which support the ancient medicalnuse of sparingly soluble lead compounds. Submicromolarnconcentrations of Pb2 ions are shown to be sufficient forneliciting specific oxidative stress responses of keratinocytes.nThese consist essentially of an overproduction of nitrogennmonoxide (NO°). Owing to the biological role of NO° innstimulating nonspecific immunological defenses, one maynargue that these lead compounds were deliberately manu-nfactured and used in ancient Egyptian formulations tonprevent and treat eye illnesses by promoting the action ofnimmune cells.