Nicotine and what else?: HPLC elution optimization for the analysis of alkaloids found in electronic cigarettes Semantic Scholar Guide cigarette lectronique : Quel taux de nicotine choisir ? Comment choisir le taux de nicotine de son e liquide ? Increased oxidative stress responses in murine macrophages exposed at the air liquid interface to third and fourth generation electronic nicotine delivery system (ENDS) aerosols ScienceDirect