| The combination of modern high-order analytical instruments and multi-way calibration methods,using“physical/chemical separation coupled with mathematical separation”to obtain super-strong separation means,can achieve direct and accurate qualitative and quantitative analysis of multiple components of interest in static or dynamic complex systems.It can solve the challenging analytical science problem that efficient and accurate quantitative analysis of multiple targets in com plex systems with unknown interference coexistence.The second-order calibration method as a fast,green,accurate,and strong universal method shows huge potential in the different scientific fields.“Food is god for the people,the safety of food is always first,and the safety of food is based on its quality.”As people pay more attention to food quality and production process,high quality and safe food producti on requires faster and more stringent standards for process control.Accurate and fast analytical techniques are essential.Therefore,the authors use high-order analytical instruments combined with second-order calibration methods to the field of food safety analysis,mainly for qualitative and quantitative analysis of illegal additives and natural conponents in chilli or edible oil samples.The details are summarized as follows:In Chapter 2:Rhodamine B?RB?,rhodamine 6G?R6G?and rhodamine 123?R123?are illegally added into foodstuff to reinforce the natural colour,because of their intensive colour,low cost and easy to obtain.However,some experiments have shown that if three mentioned dyes used in foods are gobbled by humans or animals,it can cause some side effects including reproductive carcinogenicity,neurotoxicity and chronic toxicity.Therefore,in some places,the three rhodamine dyes have been recently regarded as illegal additives in food.Accordingly,in order to safeguard the interests and safety of consumers,it is an urgent need to develop a rapid and accurate method for the determination of rhodamine dyes illegally added into foods.In this chapter,a smart and green analytical method based on the second-order calibration algorithm coupled with excitation-emission matrix?EEM?fluorescence was developed for the determination of rhodamine dyes illegally added into chilli samples.The proposed method not only has the advantage of high sensitivity over the traditional fluorescence method but also fully displays the“second-order advantage”.Pure signals of analytes were successfully extracted from severely interferential EEM data via using alternating trilinear decomposition?ATLD?algorithm even in the presence of common fluorescence problems such as scattering,peak overlaps and unknown interferences.It is worth noting that the unknown interferents can denote different kinds of backgrounds,not just a constant background.The use of“mathematical separation”strategy can be more effective and environmentally friendly.A series of statistical parameters including figures of merit,RSDs of intra-and inter-day were calculated to validate the accuracy of the proposed method.Furthermore,the authoritative HPLC-FLD method was adopted to verify the qualitative and quantitative results of the proposed method.Compared with the two methods,it also showed that the ATLD-EEM method had the advantages of accuracy,rapidness,simplicity and green,which was expected to be developed as an attractive method for simultaneous and interference-free determination of rhodamine dyes illegally added into complex matrices.In Chapter 3:During the storage of edible oil,it is easy to cause rancidity and deterioration due to its large amount of unsaturated fatty acids.Therefore,antioxidants such as propyl gallate,butylated hydroxyanisole and ethoxyquin are often added into edible oils to prevent spoilage and oxidation,as well as to increase storage time.The above antioxidants are more effective when they are used in combination.However,experiments have shown that excessive antioxidants can cause many potential hazards.Many countries have strict limits on the amount of antioxidants added.In this chapter,a green,universal ANWE-EEM method was proposed to determine the true content of three antioxidants in five common edible oil,even in the presence of overlapped fluorescence spectra and unknown interferences.The accurate qualitative and quantitative information and the true content of the target analytes in the five oil samples are obtained.In order to verify a series of performance of the method,the correlation coefficient,average recovery rate,standard deviation,sensitivity?SEN?,selectivity?SEL?,limit of quantitation?LOQ?and limit of detection?LOD?were calculated,and the results were satisfactory.Finally,in order to highlight the advantages of the proposed method,method comparison was carried out.The LOD values of PG,BHA and EQ are 0.11-2.25,0.44-1.52 and 0.2-0.65 ng mL-1,respectively,which is simple and fast,without complicated pretreatment,compared with most of chromatography methods.The analysis time is saved and the LOD is close to or even lower than that of LC-MS/MS method.Therefore,this method is expected to be applied to the quality control of edible oil for rapid,green,interference-free and accurate quantitative analysis of various target analytes.In Chapter 4:Compared with other vegetable oils,sesame oil has excellent oxidative stability due to its rich endogenous antioxi dants such as?-tocopherol and sesame lignan.In addition,it also has anti-inflammatory,anti-tumor,anti-allergy,prevention of hypertension,obesity and atherosclerosis,and other biological activities,which has aroused the research interest of scientists.Sesame lignan and?-tocopherol are often detected separately.However,they are exist in sesame oil at the same time,and their content is an important indicator for evaluating the quality of sesame oil,so it is crucial to simultaneously determine their content.Classical HPLC analysis methods often require time-consuming and tanglesome pretreatment and analysis processes.Therefore,the"mathematical separation"of alternating trilinear decomposition combined with the HPLC-DAD strategy can solve the common chromatographic problems such as peak overlaps,time drifts,baseline drifts and unknown interferences,and can realize simultaneous quantitative analysis of sesamin,sesamolin,asarinin,sesamol and?-tocopherol in different sesame oil samples.The average spiked recoveries of all target analytes were between 95.6%and 107.2%,and the results for the standard deviation,RMSEP and figures of merit were also satisfactory.Compared to some methods reported in published literatures,the proposed method is simple,efficient and universal,which has certain practical value for evaluating the quality of sesame oil. |
PDF Full Text Request