Second-order Calibration Methods Applied To Determination Of Flavonoids In Complex Systems

Chemometrics is a new branch of chemistry, which is on applying the methods of computer sciences, mathematics and statistics. First of all, the history and development of chemometrics are described in the introduction part of this thesis. Then the development of analysis in flavonols was given briefly. Based on the above, determination of flavonols in complex systems has been studied by using second-order calibration methods combining with excitation-emission matrix fluorescence and high-performance liquid chromatography. The problem of serious spectra overlapping has been successfully solved by utilizing the above method. The method can be used to determine the flavonols in complex systems in the presence of unknown interferences.In Chapter 2, a novel mathod was proposed for determination of rutin content in cosmetics by combining the excitation-emission fluorescence spectra with the second-order calibration based on the alternating trilinear decomposition (ATLD) and the self-weighted alternating trilinear decomposition (SWATLD) algorithms. The results indicated that both algorithms can be satisfactorily applied to directly determine rutin content in cosmetics, and this method is also providing a new way to the cosmetic quality control field.In Chapter 3, a simple method, second-order calibration based on the self-weighted alternating trilinear decomposition (SWATLD) algorithm, was proposed for the direct determination of kaempferol content in Ginkgo biloba L. extract injections using excitation-emission matrix fluorescence and HPLC-DAD, respectively. The results are satisfactory. Therefore, this strategy will play an important role in the field of phyto-pharmaceutical quality control.In Chapter 4, a novel and rapid method was proposed for rapid determination of glangin in human urine by combining the excitation-emission fluorescence spectra with the second-order calibration based on the self-weighted alternating trilinear decomposition (SWATLD) and the alternating penalty trilinear decomposition (APTLD) algorithms. The method didn't need the pretreatment procedure for separation such as extraction and the satisfactory results were shown that the proposed method could solve the problem of serious fluorescence spectral overlapping of the glangin and urine interferents, and it can be applied to rapid determination of glangin even in the presence of unknown interferents. In Chapter 5, second-order calibration coupled with excitation-emission fluorescence spectroscopy was applied to determine lysionotin in human urine. The predicted results of the parallel factor analysis (PARAFAC) and the self-weighted alternating trilinear decomposition (SWATLD) algorithms were both satisfactory. Though the spectra of the lysionotin and the urine were partly overlapped, this method could determine lysionotin quickly, which even in the presence of unknown interferences.