Applications Of Fluorescence Coupled With Second-order Calibration Methods In Biological Fluid And Food Analysis

Chemometrics is a developing subdiscipline of chemistry. The aim ofchemometrics is focus on extracting chemical information by applying the methodsof mathematics, statistics and computer sciences. The characteristics of modernanalytical chemistry make the determination of components of interest in complexsystem using instrumental analysis combined with chemometrics inevitable. Themulti-way calibration is one of the most active domains of chemometrics. Thesecond-order calibration methodologies have the second-order advantage whichallow for quantitation of analytes even in the presence of unexpected sampleconstituents. It can replace or enhance the ‘physical or chemical separation’ with‘mathematical separation’ strategy through separating the signals of target analytesaway from those of uncalibrated background or interferences. Such methods are usedwidely to resolve the difficult problems from various fields, especially biochemistryand pharmaceutical chemistry, food chemistry, environmental chemistry. As isknown, the fluorescence spectroscopy has high sensitivity. The research work in thisdissertation focuses on the determination of the analytes of interest in biologicalfluid and food by applying the three-dimensional fluorescence coupled with thesecond-order calibration methods. The main contents are as following.In chapter2, the composition of the cell culture medium is complicated. Itcontains many chemicals which have fluorescence properties. A newspectrofluorimetric method has been developed for the quantitative determination ofthe alpinetin content in cell culture medium samples. This method combinedthree-dimensional fluorescence with chemometric second-order calibration methodsbased on parallel factor analysis (PARAFAC) and self-weighted alternating trilineardecomposition (SWATLD) algorithms. Ethoxycarbonyl quinoline is antioxidantcommonly used by domestic and foreign. It is usually used to prolong the shelflife offeedstuff and food by protecting them against deterioration caused by oxidation. Inchapter3, a new method using excitation-emission matrix fluorescence coupled withsecond-order calibration method based on alternating trilinear decomposition (ATLD)algorithm for determining ethoxycarbonyl quinoline in milk samples is presented.The results are satisfied.In chapter4, bisphenol A (BPA) and dienestrol (DE) are endocrine and disrupting chemicals. They will have bad effect on human health and theenvironment. They are potential substances in the milk. The application offluorescence techniques with the aid of the second-order calibration method to thequantitative analysis of them in milk samples is advantageous because of the highsensitivity that can be achieved. In chapter5, diethylstilbestrol (DES) is one of thenonsteroidal estrogen. Some studies show that it can cause teratogens andcarcinogenic effects. DES is poor degradable. Residues of DES exist extensively inanimals, source of water and soil. That can create a vicious circle of environmentalpollution. Moreover, eating the animal products with the residues of DES canincrease the risk of cancer. DES without inherent fluorescence properties can reactwith concentrated sulphuric acid. After the reaction, the product has strongfluorescence intensity. At different pH levels, the aqueous solution of the productshows different existing states. We obtain the three-way data by scanning thesamples whose pH values are different using the luminoscope. The relativedistributions of hydrolysate at the situation of different pH levels are gained, sincethe chemometric method can extract useful information from the three-way data.