Research On The Detection Of Food And Environmental Pollutants By Combining Dispersive Solid Phase Extraction And High Performance Liquid Chromatography

Food and environmental safety have become the focus of scientific and technological circles and the public.It is also an important issue related to human health.Food and environmental safety monitoring has become the key to addressing food safety and environmental safety.The frequent safety accidents caused by pollutant residues in environment and agricultural products threaten human health and safety.It is particularly important to develop simple,rapid,efficient and widely used methods for effective control of pollutant residues.This paper mainly established a highly sensitive method combined dispersive solid phase extraction?DSPE?pretreatment technology with high performance liquid chromatography?HPLC?to detect harmful substances in food and environmental samples,and provided technical support for food and environmental safety testing.The main research contents of this paper are as follows:Chapter one:We have sketched the HPLC,classification of pretreatment techniques,and the introduction,the main research directions,preparation methods and activation methods of metal-organic frameworks?MOFs?materials.Chapter two:To increase sensitivity and accuracy of the method for determination of nitrobenzene compounds?NBs?,the amino-functionalized metal-organic framework?UiO-66-NH₂?was used as the adsorbent for DSPE to pretreat eight NBs in environmental water samples.Grounded on the synergistic effect of hydrogen bonding(formed by nitro groups of NBs and amino groups of the MOFs and the tendency interaction?between nitro groups of NBs and Zr containing moiety in the MOFs scaffold?,the adsorption capacity was high improved.In this chapter,a fast,sensitive and accurate method for the determination of eight main NBs was developed by combining DSPE with HPLC.The established pretreatment method is expected to be widely applied to the enrichment and extraction of NBs in water samples.Chapter three:The abuse of Plant growth regulators?PGRs?has increasingly become the focus of the world.Considering the role and harm of PGRs to human health,it is important to simultaneously determine a variety of PGRs.In this paper,ZIF-8 was used as a DSPE adsorbent,combined with high performance liquid chromatography-diode array detector?HPLC-DAD?to establish a highly sensitive detection method for determination of 9 PGRs.Using the established method to detect and analyze 9 PGRs in fruit samples showed excellent performance.Chapter four:Specific adsorption is key to improve the recovery and remove the interference for solid phase extraction?SPE?.In this work,sulfonamides?SAs?in meat samples were extracted by using a highly stable and mesoporous MOFs?UiO-67?as an adsorbent.Owing to the?-?interaction,hydrophobic interaction and hydrogen bonding effect between the SAs and the adsorbent,as well as the appropriate pore size of UiO-67 to SA molecules,the extraction ability of UiO-67 for SAs obviously improved,thereby the sensitivity of the proposed method was improved.By combining the HPLC-DAD,a sensitive and selective method for determination of SAs was successfully developed.