Multi-way calibration coupling with fluorescence spectroscopy to determine magnolol and honokiol in herb and plasma samples

Abstract

This work presents a novel approach for the simultaneous determination of mixtures of magnolol and honokiol in herb and plasma samples by combining the sensitivity of molecular fluorescence and the selectivity of the second-order calibration method. The excitation–emission matrix fluorescence data were processed by applying the second-order calibration method based on parallel factor analysis (PARAFAC) and self-weighted alternating trilinear decomposition (SWATLD) algorithms. The results showed that the method could solve the problem of analyzing complex multi-component samples, using “mathematics separation” to replace some or enhance chemical separation. The recoveries from spiked herb samples were in the range of 93–104% for magnolol and 89–98% for honokiol, and those from spiked human plasma samples were in the range of 98–105% for magnolol and 94–96% for honokiol. In herb samples, the LOD values of magnolol were 0.51 μg ml⁻¹ and 0.45 μg ml⁻¹, and those of honokiol were 0.37 μg ml⁻¹ and 0.24 μg ml⁻¹, when using PARAFAC and SWATLD. For human plasma samples, the LOD values of magnolol were 0.93 μg ml⁻¹ and 0.64 μg ml⁻¹, and 0.79 μg ml⁻¹ and 0.42 μg ml⁻¹ for honokiol. The results demonstrated that this method had both high recovery and good precision for the determination of honokiol and magnolol. The proposed method avoided preconcentration and had a simple disposal process, so it considerably decreased the analysis time and the experimental costs. Thus, it can be considered as a green analytical procedure for magnolol and honokiol determination in herb and plasma samples.