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A simple stochastic resonance algorithm based on linear modulation was developed to amplify and detect weak chromatographic peaks. The output chromatographic peak is often distorted when using the traditional stochastic resonance algorithm due to the presence of high levels of noise. In the new algorithm, a linear modulated double-well potential is introduced to correct for the distortion of the output peak. Method parameter selection is convenient and intuitive for linear modulation. In order to achieve a better signal-to-noise ratio for the output signal, the performance of two-layer stochastic resonance was evaluated by comparing it with wavelet-based stochastic resonance. The proposed algorithm was applied to the quantitative analysis of dimethyl sulfide and the determination of chloramphenicol residues in milk, and the good linearity of the method demonstrated that it is an effective tool for detecting weak chromatographic peaks.

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In this paper, a useful method for screening and analyzing the potential bioactive components in bioassay-guided fraction (SF-11) from Shaofu Zhuyu decoction was developed using human umbilical vein endothelial cell (HUVEC) extraction and high-performance liquid chromatography coupled with Q-TOF/MS spectrometry. In addition, the protective effects on HUVEC damage induced by adrenaline in vitro were also investigated. The results showed that SF-11 significantly inhibited the endothelin (ET) release and reversed the NO secretion of HUVEC (p < 0.05), and promoted the PGI(2) release of HUVEC (p < 0.05). Two effective components, paeoniflorin and typhaneoside, from SF-11 were screened and identified using live cell extract and HPLC coupled with Q-TOF/MS spectrometry. The compounds, paeoniflorin and typhaneoside, showed significantly inhibiting effects on the ET release and reversing of NO secretion of HUVEC (p < 0.05), with similar effects to SF-11, and promoting the PGI(2) release of HUVEC at the concentration of 0.208 and 0.013 micromol/mL, respectively (p < 0.05). These data indicated that the method of live cell extraction coupled with HPLC-MS technology is feasible, rapid and useful for screening and analyzing potential bioactive components from TCMs.