A novel magnetic method using polystyrene modified magnetic nanoparticles to perform thermo-headspace extraction was successfully developed for extraction and preconcentration of volatile organic components in dry Traditional Chinese Medicine (TCM) based on gas chromatography-ion trap/mass spectrometry with a ChromatoProbe direct sample introduction device. The dried fruit of Amomum testaceum Ridl. was used as the object TCM. The optimum parameters of headspace magnetic solid-phase extraction were investigated, in which desorption solvent ethyl acetate played a key role in this method, and the headspace extraction temperature of 90 °C and the headspace extraction time of 15 min finally decided. Headspace solid-phase microextraction method was also used to analyze volatile compounds in the TCM to compare with the proposed method. The results show that 60 components were identified totally by two methods; most of the low boiling point chemical compounds are isolated by this new method. In this work, an environmental-friendly and cheap analytical method was established, and a new approach to analyze volatile compounds in dry Traditional Chinese Medicine was also provided.Magnetic nanoparticles as adsorbents extract the volatile compounds in the Traditional Chinese Medicine.

Electrochemical detection of eluent of column chromatography is considerably simple for monitoring the purification process, In this detection system, electrolyte is needed to decrease the resistance of solution during the electrochemical detection. However, in the case of natural medicine purification, it is highly challenging to added electrolyte into the purification process without influencing the purification efficiency. Herein, on the basis of Paraffin-graphite Powder electrode, an online electrochemical detector was developed without any additional electrolyte. The cyclic voltammograms of myricetin in ethanol-water (80%, V/V) as mobile phase is obtained directly by using the solid acid characteristic of Nafion N-324 membrane in the micro-gap flow cell. Peristaltic pump stimulates the chromatographic process, and then it realizes the online detection of eletroactive substances in the eluent at 0.53 V. Peak area is linear with the myricetin concentration in the range of 2.0 × 10−5−1.0 × 10−3 M, and the linear equation is A = 2.7227c + 0.4341, r = 0.9976. Furthermore, the detector achieves the online detection of 30% AOB (antioxidant of bamboo leaves) purified by macro porous resin without any supporting electrolyte in 80% (V/V) ethanol-water at 0.62 V, and the amperometric time-current (t–i) curve during the purification process was presented. The result indicated that the detector is feasible for application.