Study On The Applications For Determination Of Polvamines Based On Capillary Electrophoresis Combined With Electromembrane Extraction

1. PrefaceCapillary electrophoresis (CE) is an efficient, fast and economic micro-separation detection method, which makes it being used more widely in analysis of complex samples, such as the drug, food, environmental and biomedical. This chapter introduced the basic principles and related applications of capillary electrophoresis, capacitively coupled contactless conductivity detector and electrical membrane micro extraction. This paper intends to combine the high separation efficiency of CE with the common type of C4D and highly enriched performance EME, which makes up the EME/CE-C4D system, being used to explore its analysis and applications in detection of multi-amine compounds. This method can detect multiple protonated amines, without derivatives and also environmentally friendly.2. Electromembrane extraction of salivary polyamines followed by capillary zone electrophoresis with capacitively coupled contactless conductivity detectionElectromembrane extraction (EME) as a novel sample preparation technique was firstly applied for the purification and enrichment of four polyamines mainly present in saliva samples. These four target analytes, Putrescine, Cadaverine, Spermidine, and Spermine, were directly determined by CE with capacitively coupled contactless conductivity detection (CE-C4D) after EME procedure. Several factors affecting extraction efficiency, electrophoretic separation, and detection were investigated. Under the optimum conditions, four polyamines could achieve baseline separation within 22 min, exhibiting a linear calibration over three orders of magnitude (r2>0.999); the highest enrichment factor could reach 106-fold (for Spermidine), and the LODs were in the range of 1.4-7.0 ng/mL. The proposed EME/CE-C4D method has been successfully applied to analyze human saliva samples with recoveries in the range of 78%-97%.3. Electromembrane extraction of diamine plastic restricted substances in soft drinks by capillary electrophoresis coupled with contactless conductivity detectionEthanediamine and hexamethylendiamine are two diamine plastic restricted substances commonly existing in food contact materials. A novel method based on capillary electrophoresis with capacitively coupled contactless conductivity detection (CE-C4D) method has been developed for direct determination of above two diamines, and the detection sensitivity has been significantly improved based on electromembrane extraction (EME). Ethanediamine and hexamethylendiamine could be well separated from their aliphatic diamine homologs as well as the common inorganic cations within 25 min. Several factors affecting extraction efficiency were investigated. Under the optimum conditions, the highest enrichment factor of ethanediamine and hexamethylendiamine were 718-fold and 660-fold, respectively, and the limits of detection were both 0.04 ng/mL. This proposed method has been successfully used to determine these diamines in different bottled drinks including purified water, mineral water, and Sprite soft drinks, providing an alternative method for the sensitive analysis of restricted plastic substances in soft drinks.