ISO 20714:2019 E-liquid – Determination of nicotine, propylene glycol and glycerol in liquids used in electronic nicotine delivery devices- Gas chromatographic method

ISO 20714:2019 E-liquid – Determination of nicotine, propylene glycol and glycerol in liquids used in electronic nicotine delivery devices- Gas chromatographic method. This document specifies an analytical method to quantify the nicotine, propylene glycol and glycerol content in e-Iiquids by gas chromatography. 2 Normative references There are no normative references in this document. 3 Terms and definitions For the purposes of this document, the following terms and definitions apply. ISO and IEC maintain terminological databases for use in standardization at the following addresses: — ISO Online browsing platform: available at https://www.iso.org/nhp — IEC Elect ropedia: available at htp://www.electrpedia.org/ 3.1 e-liquid liquid or gel consumable which may or may not contain nicotine intended for transformation into an aerosol and then inhaled with an electronic nicotine delivery device (3.2) 3.2 electronic nicotine delivery device device used to transform an e-liquid (11) into an inhalable aerosol 4 Principle The e-liquid sample is diluted with a solution of isopropanol containing internal standard(s). The nicotine, propylene glycol and glycerol content of the diluted sample is analysed by capillary gas chromatography with flame ionization detection (GC-FID) and quantified by using an internal standard. 5 Reagents Use only reagents of recognized analytical grade. 5.1 Carrier gas: helium (CAS: 7440-59-7) or hydrogen (CAS: 1333-74-0) of high purity. 5.2 Auxiliary gases: hydrogen (CAS: 1333-74-0) of high purity and air for the flame ionization detector. 5.3 Isopropanol (CAS: 67-63-0), minimum purity 99 %, used with internal standard(s) to prepare the dilution solution. 5.4 Internal standards of high purity: quinaldine (CAS: 91-63-4), 13-butanediol (CAS: 107-88-0), n-heptadecane (CAS: 629-78-7), n-octadecane (CAS: 593-45-3). Anethol and other appropriate internal standards may be used after assessment of their purity and determination that the internal standard does not co-elute with other components in the dilution. The peak area of the internal standard on samples should be monitored for consistency. In cases where inconsistencies are found, analysis of a diluted sample without the internal standard should be performed to confirm the absence of a peak in the extract eluting at the same time as the internal standard. 5.5 Dilution solution: isopropanol (53) containing an appropriate concentration of the internal standard (5.4), e.g. 0,2 mg/mi of quinaidine, 1 mg/ml of 1,3-butanediol, 1 mg/mi of n-heptadecane or 1 mg/ml of n-octadecane (5.4). 5.6 Reference substances 5.6.1 Nicotine (CAS: 54-11-5), of known purity not less than 98 %. Nicotine salicylate (CAS: 29790-52-1) of known purity not less than 98 %...