| With the advent of the information age marked by the computer applications,modern analytical chemistry has gone through instrumentation,computerization,intelligence and informatization and has become an integrative and advanced subject which is based on different subjects such as chemistry,mathematics,information science,and physics.Moreover,with the emergency of new multi-channel high order analytical instruments and intelligent instrumental data acquisition,the modern analytical chemistry is being in an unprecedented“data tsunami”stage characterized by multi-dimensional and magnanimity of the measurement data.As one branch of analytical chemistry,chemometrics can extract the needed useful information by processing and analyzing the complex measurement data,providing a new way and powerful method to handle the“data tsunami”problem.Chemical multiway calibration and resolution is an important research field and research hotspots in chemometrics.Owing to the prominent“second-or higher-order advantage”,multiway calibration methods can be used for the accurately quantitative analysis of multiple target analytes even in the presence of uncalibrated interferences,by using ingenious“mathematical separation”to displace or strengthen traditional“physical or chemical separation”,and therefore can be combined with modern analytical instruments to develop green and high-efficiency analytic strategies.So far,this analytical strategy has aroused great concern and has been increasingly recognized by the international and domestic researchers.Moreover,it has been broadly used in many fields like environment,food,biological medicine and life sciences.Through a detailed investigation and in-depth analysis for the development tendency and application research of multiway calibration methods,and in view of the advantages and disadvantages of modern high-order analytical instruments,this dissertation mainly focuses on the development and application of accurate quantitative analytical strategies based on high-order instruments combined with chemical multiway calibration,the simplification of expensive analytical instruments,the development of some novel strategies to handling nonlinear high-order instrumental data as well as the exploration analytical advantages of data fusion,which is likely to be supplementary,green,economic,high efficient and environmentally friendly.Study works presented in the dissertation are as follows:Part ?:Chemical multiway calibration assisted high performance liquid chromatography-diode array detection strategy for accurately quantitative analysis of multi-target analytes in food and biological systemsIn Chapter 2,a novel chemometrics-assisted high performance liquid chromatography-diode array detection(HPLC-DAD)analytical strategy was proposed for simultaneous and fast quantification multi-class food additives in beverages.Different kinds of beverages,which contain diverse unknown interferences,can be directly injected into a chromatographic system after a simple dilution or pretreatment step.Owing to the prominent“second-order advantage”of ATLD algorithm,all food additives were accurately resolved by using the proposed strategy,even in the presence of heavy overlapped peaks and unknown interferences.The analytical results showed that the proposed method is simple,timesaving,sensitive and universal,and can avoid complex purification and separation preprocessing steps.Moreover,to further validate the reliability of the method,the prediction results were compared with that obtained from a traditional HPLC-UV method.The statistical tests showed that there were neraly no significant differences for quantitative results between two methods,and the proposed was more accurate.These advantages highlighted that the proposed could be used as a reliable tool to determine food additives and quality monitoring in different complex beverages.In Chapter 3,chemical multiway calibration coupled with high performance liquid chromatography-diode array detection(HPLC-DAD)analytical strategy was applied for fast and sensitive quantification of eight small molecules in human urines.All the analyses were based on a short C18 column with the chromatographic system operating in isocratic mode and all analytes can be successfully quantified within 6min.The second-order HPLC-DAD data acquired were handled intelligently by two typical chemometrics tools including alternating trilinear decomposition(ATLD)and multivariate curve resolution-alternating least squares(MCR-ALS).Reasonable resolution and satisfactory quantification results were obtained regardless of the complex matrix interferences from the urine samples and the second-order advantage was fully exploited.Moreover,the analytical results of two chemometric methods were compared with that obtained from HPLC-UV method and the results of both methods were consistent with each other.Meanwhile,compared with classic HPLC-UV method,the proposed method could take extra advantages such as increased selectivity and sensitivity,shorter analysis time,undemanding elution conditions benefit from multivariate calibration.Finally,ATLD and MCR-ALS have slightly different in the aspect of applicability and flexibility.The method was shown as a promising means for fast and sensitive determination of small molecules in human urine and also for fast diagnosis or surveillance in related diseases.Part ?:Analytical strategy for rapid and sensitive detection of multiple targets in complex food matrices based on chemical multiway calibration assisted liquid chromatography-mass spectrometryIn Chapter 4,a smart analytical strategy that combines liquid chromatography-full scan mass spectrometry with the chemical mutilway calibration method based on the alternating trilinear decomposition(ATLD)algorithm was developed for simultaneously determination of seven estrogens in infant milk powders.By virtue of“mathematical separation”of second-order calibration methods,the proposed strategy required no tedious mass condition optimization and more sophisticated instrumentations.The seven estrogens were rapidly eluted out within 7 min under a simple gradient condition and then detected by mass spectrometry operated in full scan mode.With the aid of the prominent“second-order advantage”of the algorithm,specific qualitative and quantitative information about the target analytes could be extracted from the complex milk system even in the presence of considerable peak overlaps,baseline drifts and unknown interferences.Average recoveries of the seven estrogens in two spiked infant milk powder samples were in the range of 91.2-104.2%with the relative standard deviations(RSDs)lower than 12.5%,and the limits of detection(LOD)ranged from 0.07 to 2.49 ng m L-1.Besides,to further confirm the feasibility and reliability of the proposed method,the same batch of samples was analyzed using the MRM method,and the statistical tests showed that no significant difference existed between the two methods.The proposed method is fast,accurate,low-cost and sensitive and could provide satisfactory prediction results in real infant milk powder samples.Part ?:Chemical multiway calibration for accurately analysis of non-linear multiway data and the development of data fusion methods as well as the exploratory research on its analytical advantagesIn long-term process analysis and quantifications based on different fluorescence instruments,the fluorescence signal of the instrument would be fluctuated or even changed due to aging of the xenon lamp or temperature changes,resulting in the signal instability or variation of EEM in different time.These problems will have a severe impact on the performance of chemomtrics-assisted EEM analytical strategy.In chapter 5,a chemometrics-assisted calibration transfer strategy was proposed to solve the EEM signal instability and variation and maintain the prominent“second-order advantage”.Moreover,the proposed strategy was applied to simultaneous and fast determination of three agrochemicals in environmental samples.The proposed strategy was validated by using simulated and experimental datasets.Satisfactory analytical results revealed that the proposed strategy can replace the full recalibration strategy to solve EEM signal instability and variation,and can get successful resolution and quantification even in the presence of overlapped peaks and unknown interferences.The developed strategy takes advantage of less experimental effort and cost,which can be an alternative one for fast screening of agrochemicals and long-term process analysis in environmental samples or related food matrices.In chapter 6,an effective strategy that combines the liquid chromatography-mass spectrometry with chemometric methods was developed for simultaneous determination of four estrogens and eight small molecules in water and human urines,respectively.For the entire chromatographic run,a flexible varying quadruple fragmentor voltages strategy was adopted,allowing each analyte to achieve highly sensitive and selective results and a hard chromatographic segmentation can be avoided.The raw LC-MS data was fused and partitioned and then the processed data was resolved by using second-order calibration method based on alternating trilinear decomposition(ATLD)algorithm.The analytical results showed that the fused data can provide higher sensitivity and more reliable results while the partitioned data offered higher selectivity for some specific analytes.Moreover,the proposed strategy can take extra analytical advantages in terms of higher sensitivity and more reliable quantitative results when compared with LC-MS(with single fragmentor voltage)strategy and shows nearly the same capability in analytical quality with classic MRM method. |
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