| Chromatography is a powerful separation technology. Nowdays, it has been widely used in analytical chemistry field, e.g. food safety, pharmaceutical analysis, environment inspection, toxicological analysis, quality control, biological chemistry, clinical etc. Among numerous chromatography methods, high-performance liquid chromatography (HPLC) and gas chromatography (GC) are the most popular tools due to high separation efficiency, improved selectivity, the fast speed of analysis.Electrochemiluminescence (ECL) is the light-emitting phenomena initiated by electrochemical method. It is the combination of CL and electrochemistry. Whilst retaining the advantages of the very low detection limits and the wide linear dynamic range inherent to conventional CL method, ECL also offers many additional advantages, e.g., controllable chemiluminescence reaction, reduced reagent consumption and in situ ECL generation. However, the poor Selective of this method limits its further application. To widen its application, separation technology should be coupled with ECL. HPLC coupled to ECL detection represents an interface between the selectivity of a powerful separation method and the sensitivity of this detection technique.GC/MS is a powerful analytical tool due to high qualitative ability of MS and efficient separations for analytes. When GC/MS was used in food analysis, interfering substances can be separated from analytes by GC and analytes can be accurate detection by MS. Thus, GC/MS is a proper choice to detect thermally stabile, low-polar and volatile analytes in food matrices. With these distinguished advantages, GC/MS is extensively employed for food safety.In this Paper, Advances in HPLC, ECL sensor and GC/MS research in the past years are reviewed. HPLC-ECL system and the application of GC/MS in food safety are also introduced briefly.Nepem-105D perfluorinated ion exchange solution and Nepem-211perfluorinated ion exchange conductance membrane which not only has high capability and high capacity for immobilization of Ru(bpy)32+, but also has high conductivity were used to modify electrode. On this basis, a simple ECL flow cell with low dead volume and good compatibility for HPLC analysis was developed. Nepem-105D has a branched chain perfluorinated vinyl ether structure on a skeletal structure similar to that of PTFE. Since the C-F bond length is short, the bond energy is high (486kJ/mol) and electron-rich fluorine atoms are strongly electronegative, resulting in mutual repulsion between adjacent fluorine atoms and fluorine atoms along the zigzag polymer C-C chain spiral distribution. Also, because the fluorine atomic volume is bigger than the hydrogen atom, it provides better coverage of the C-C chains, forming a low surface free energy fluoride protection layer. As Nepem-105D has good thermal stability, chemical stability and high exchange capacity, Ru(bpy)32+can be exchanged through the ion-exchange process and electrostatic adsorption. Thus, it can be used to develop a simple single Pt wire HPLC-ECL detector. Nepem-211perfluorinated ion exchange conductance membrane is made by new resin flow technology based on Nepem-105D. Resin flow technology can combine with adulterate technology, so Nepem-211has many outstanding features:it not only has the high tensile strength, high selection, isotropy, high conductance (0.1s/cm), but also the effect of self-humidifying and with low linear expansion. It has been applied in fuel cell, vanadium batteries, electrolyzer, electrodialysis and solid electrolyte membrane of electrochemical sensors. Nepem-211membrane has higher exchange capacity, so more Ru(bpy)32+can be immobilized. Immobilized Ru(bpy)32+cannot migrate into the electro-inactive hydrophobic region with time, and it is not destroyed upon exposure to mobile phase containing high organic content. So the flow sensor has high sensitivity and a long life. It is very suitable for HPLC analysis. Based on the optimal conditions of ECL detector and chromatographic separation, a new HPLC-ECL system was established. This system was used to detect trace pharmaceuticals in food and biological samples (eg. blood, urine). In addition, GC/MS was used to detect dimethyl fumarate in cakes and49kinds of pesticide residues in plant-based foods.The main researches are as follows:A simple, stable and sensitive ECL sensor was developed based on tris(2,2-bipyridyl)ruthenium(II) immobilized on the surface of a Pt wire with Nepem-105D ion exchange solution. It contains only two Pt wires and a matrass. Under optimal conditions, six repeat injections of0.3μg ml-1OFL solution was3.6%and the inter-day precision was6.8%on three consecutive days. The sensor was used as a detector of HPLC. In this HPLC-ECL system, luminescence reagent Ru(bpy)32+was immobilized and can be reused, therefore, no Ru(bpy)32+delivery system is needed, the experimental setup was simplified. There is no post column reagent addition, which would dilute analytes, potentially leading to chromatographic band-broadening. Furthermore, the reagent cost and its contamination to the environment were reduced. The HPLC-ECL was used for the determination of multiple target fluoroquinolone residues in milk and three antiemetic drugs in human serum successfully.A sensitive and robust electrogenerated chemiluminescence (ECL) flow sensor was developed in this work. It was based on Ru(bpy)32+immobilized with Nepem-211membrane, which has good electrical conductivity, and high exchange capacity for immobilization of Ru(bpy)3+. The flow sensor has good stability. The precision of11repeat injections of8.0ngμL-1erythromycin,4.0ngμL-1clarithromycin solutions were1.40%and1.76%, respectively. The proposed flow sensor has been used as a post-column detector in HPLC for determination of erythromycin and clarithromycin in honey and pork and doxepin, amitriptyline, and clomipramine in human urine.A method of one step rapid extraction of dimethyl fumarate in cakes using acetonitrile and n-hexane saturated each other was established. Dimethyl fumarate and fat impurities can be extracted by acetonitrile and n-hexane, respectively, at the same time. This pre-treatment method is simple, rapid and reliable. GC-ECD was used to analyze dimethyl fumarate of food at the first time in this study. Furthermore, it was compared with GC-FID and CG/MS, the sensitivity of GC-ECD method is higher than GC-FID method.A method for rapid determination of49kinds of pesticide residues in plant-based foods by GC/MS was established. The pesticide residues in vegetable samples and dry plant-based foods were extracted with acetonitrile and acetone, respectively. The extracting solution was clean-up by SPE after being concentrated.286vegetable samples,30edible mushrooms and35tea bags were analyzed in three consecutive years. The pesticides residue in tea bags, leafy vegetables and fresh edible mushrooms were higher than dry edible mushrooms. According to GB2763-2012, the pesticides level of2.10%vegetables exceeded maximum residue limits. |
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