Research On Food And Drug Safety Detection Using Second-order Calibration Methods

With the development of high-order equipment and computer science, a large number of automatic collection and transmission of data becomes easy, but it leads to a more difficult question, that how to deal with and resolve these a large number of chemical raw measured data and extract useful chemical information. Obviously, this can never be analyzed by experienced workers and a simple calculation, and it must be with the aid of this powerful tool chemometrics. In numerous theories and methods of chemometrics, second-order calibration method is probably one of the most application value of research, mainly because of its unique "second-order advantage": By utilizing the green and smart "mathematical separation" to replace or enhance conventional "physical or chemical separation", it can make the direct, simultaneous, rapid and accurate quantification of multi-components of interests even in the presence of unknown interferences in the analysis system. This strategy has been increasingly valued and applied. Combined with the strategy, the author carries out the relevant research work about the food and medicine for their quality and safety control. The main contents of this dissertation are as follows:In Chapter 2, Tertiary butyl hydroquinone (TBHQ) and norepinephrine dihydro guaiacol (NDGA) are synthetic phenolic antioxidants which are commonly used in edible oils. Conventional spectrophotometry can not avoid the overlapped peaks and unknown interferences by selecting a special wavelength because the fluorescence spectra of the two compounds overlap with each other seriously and there are a lot of unknown fluorescence interfering compounds in oils. A new approach for simultaneous determination of Tertiary butyl hydroquinone (TBHQ) and norepinephrine dihydro guaiacol (NDGA) in edible oils by coupling excitation-emission matrix fluorescence with second-order calibration methods based on the alternating normalization weighted error (ANWE) algorithm. The proposed method avoids preconcentration and elution procedures and uses very small amounts of organic reagents and the quantification of TBHQ and NDGA are accomplished using green-chemistry principles.In Chapter 3, A novel method is developed for simultaneous determination of naphazoline hydrochloride (NAP) and pyridoxine hydrochloride (VB6) in commercial eye drops by using excitation-emission matrix fluorescene coupled with second-order calibration methods based on the alternating trilinear decomposition (ATLD) algorithm. The proposed approach can give quantitative results in the presence of unknown background interferences of the eye drops by utilizing the "mathematical separation" of second-order calibration methods instead of traditional "physical or chemical separation". The results were in good with the labeled contents. To further confirm the feasibility and reliability of the proposed method, the same batch samples were analyzed by multiple reaction monitoring (MRM) based on LC-MS/MS method. t-test demonstrated that there are no significant differences between the prediction results of the two methods. The satisfactory results obtained in this work indicate that the use of the second-order calibration method coupled with the EEM is a promising tool for industrial quality control and pharmaceutical analysis due to its advantages of high sensitivity, low-cost and simple implementation.In Chapter 4, Chinese medicine is the treasure of Chinese nation, but facing the difficult embarrassment into the mainstream of the international pharmaceutical market. One of the main reasons are the imperfection of the traditional Chinese medicine quality standard system in our country and the means of detection is relatively backward. The objective factors which restrict the development of the Chinese traditional medicine standard are traditional Chinese medicine system is complex,contains many ingrddients and traditional chromatographic methods are difficult to make all the ingredients to achieve the effect of baseline separation. In chapter 2, to overcome the above disadvantages, a novel strategy for quick determination of the main active compound andrographolide and dehydroandrographolide in Andrographis paniculata and Compound Chuanxinlian tablets was employed by using high performance liquid chromatography-diode array detection (HPLC-DAD) combined with second-order calibration method based on Alternating Trilinear Decomposition (ATLD) algorithm. The method has no pretreatment except the samples were extracted with methanol by ultrasound extraction for 20 min. Satisfactory results show that this simple and efficient method is a reliable and practical mean for simultaneous determination active ingredients of traditional Chinese medicine containing complex backgrounds and greatly promote the study of quality control of Chinese herbs.In Chapter 5, A new chromatographic methodology is presented for fast analysis of eight preservatives in different brands of mask samples:methyl 4-hydroxybenzoate (MPB), ethyl4-hydroxybenzoate (EPB), propylparaben (PPB), butylparaben (PPB), phenoxyethanol, (EGM), salicylic acid (SA), methylisothiazolinone (MIT),3-iodo-2-propynyl N-butylcarbamate (IPBC). The proposed strategy utilizes the "mathematical separation" of second-order calibration methods instead of traditional "physical or chemical separation" to avoid the pretreatment process and shorten analysis time and reduce the use of organic solvents. Satisfactory quantitative results are obtained even in the presence of unknown interferences and co-eluted peaks. Therefore, this method is expected to be a more routine approach in cosmetic quality control.