Phenol Toluol extraction (PTex) carried out two steps organic-phase separation: first pH neutral phenol–Toluol extraction separated RNA and protein from DNA: RNA and proteins to the top aqueous phase but DNA and membranes in the interface. Aqueous phase then went through two rounds acid-phenol extraction, resulting RNA in the top aqueous phase, proteins bottom organic phase and RNA-protein complexes in the interface. After carefully isolated the interface, ethanol precipitation was carried on for purifying RNA-protein adducts (Urdaneta et al, 2019; Smith et al, 2020)