Visual Volatile-Compound Fingerprint Based on Headspace Gas Chromatography-Ion Mobility Spectrometry Combined with Chemometrics Analysis and Exploration in the Authentic Identification of Lonicerae japonicae flos

Headspace gas chromatography-ion mobility spectrometric (HS-GC-IMS) fingerprint of volatile organic compounds (VOCs) in Lonicerae japonicae flos (LJF, Jinyinhua in Chinese) was developed. This method, combined with chemometrics analysis, was explored in the identification of authentic LJF. Seventy VOCs were identified from LJF, including aldehydes, ketones, esters, etc. The developed volatile-compound fingerprint based on HS-GC-IMS coupled with PCA analysis can successfully discriminate LJF from its adulterant: Lonicerae japonicae(LJ, called Shanyinhua in China) and can equally discriminate the LJF samples from different geographical origins of China. Total of four (compound 120, compound 184, 2-heptanone and 2-heptanone#2) and nine VOCs (styrene, compound 41, 3z-hexenol, methylpyrazine, hexanal#2, compound 78, compound 110, compound 124 and compound 180) were exploited, which might serve as the chemical markers for the difference of LJF, LJ and LJF from different regions of China. The result showed that the fingerprint based on HS-GC-IMS combined with PCA exhibited distinct advantages, such as rapid, intuitive and powerful selectivity, which demonstrated great application potential in the authentic identification of LJF.