Applications Of Second-order Calibration Methods In Fluorometric And Chromatographic Analysis

Chemometrics is a developing composite discipline of chemistry. The main focus of chemometrics is on applying the methods of mathematics, statistics and computer sciences to extracting chemical information, to designing the optimal scheme for chemical measurements and to elucidating the data collected from chemical measurements.The second-order calibration methodologies can deal with some traditional difficult problems because of the second-order advantage. The chemometric methodologies coupled with higher-order analytical instruments can improve or replace the"chemical separation"with"mathematical separation", enable accurate and reliable determination of the analyte concentrations even in the presence of uncalibrated interferents.In this paper, the authors utilized the analytical instruments such as EEMs and HPLC-DAD, coupled with second-order calibration methodologies, and did some work in the research of complex multi-component systems. Studies presented in the thesis primarily deals with the following aspects:In Chapter 2, it proposed a new approach for direct determination of arctiin content in plasma samples as well as a Chinese medicine (Arctium lappa L.) by the combination of excitation-emission matrix fluorescence and second-order calibration methods based on the parallel factor analysis (PARAFAC) and the alternating normalization-weighted error (ANWE) algorithms. The estimated content of arctiin in arctium lappa L. obtained by fluorescence determination was also satisfactory compared with that of the HPLC method. It can be seen that the suggested methods can be employed to directly determine arctiin, even in the presence of unknown and un-calibrated interferences, only with a simple pretreatment procedure.The rhubarb is one of the most popular traditional Chinese herbal medicines. The main active constituents of rhubarb have been reported to be anthraquinones, such as emodin and chrysophanol. In Chapter 3, it was tried to use three-way excitation-emission matrix fluorescence combining chemometrics second-order calibration algorithms, including the alternating penalty trilinear decomposition (APTLD) algorithm and the alternating normalizationweigh (ANWE) algorithm, to determined emodin and chrysophanol even in presence of urine background interferents. Though the peaks of the analytes were heavily overlapped and urine background interferents coeluted with the compounds studied, good resolved results could be obtained. But it is a pity that the estimated content of the emodin is not acceptable, it maybe owe to the reaction of the emodin with the urin background interferents and then the fluorescence of emodin had been decreased. Thus, it only can obtained satisfactory estimated results of the chrysophanol in the urine by using the method mentioned.In Chapter 4, HPLC-DAD coupled with chemometric second-order calibration method based on ATLD algorithm was applied toβ-adrenergic receptor-blocking agent in body fluids. Though the chromatographic and spectral peaks of the analytes were heavily overlapped and interferents coeluted with the compounds studied, good recoveries of the analytes could be obtained.Sulfonamides constitute a group of drugs which are widely used in veterinary. Their metabolism process are slow in animal body, thus, residues of these drugs may remain in food of animal origin. In Chapter 5, a new method based on the use of HPLC-DAD coupled with the alternating penalty trilinear decomposition (APTLD) algorithm was applied to the rapid determination of sulfonamides in milk samples. Though the chromatographic and spectral peaks of the components were highly overlapped, good quantitative results could be obtained owing to the second order advantage. The application of second-order calibration methodologies provides a new technique to food analysis.