Studies On Detections Of Histamine

Histamine (HA) is a biogenic amine, which is derived from the decarboxylation of the amino acid histidine. It exists in a wide variety of food and organisms, especially in fermented food. It is also a substance that plays a major role in many allergic reactions. The thesis mainly includes the following three parts: 1. determination of aniline by capillary electrophoresis with electrochemical detection (CD-ED) 2. Determination of histamine and histidine by capillary electrophoresis with electrochemical detection.3.determination of histamine and histidine by reversed phase high performance liquid chromatography (RP-HPLC).In chapter 1, using o-phthaldehyde (OPA) as a pre-column derivative agent, mercaprant was replaced by sulfite and CE-ED method was applied to simultaneously determine p-toluidine, p-phenylenediamine and aniline. The result shown that OPA- sulfite could react with primary amine and three analytes were base-line separated. Compared with mercaprant , sulfite has some advantages such as tasteless, stable and virulent.In chapter 2, using OPA as a pre-column derivative agent, histamine and histidine were determined by CD-ED. The design of the CE-ED system was based on the end-column approach in which the working electrode was simply placed at the outlet of the capillary. A 300μm diameter carbon disk electrode was used as the working electrode and the 50 mmol/L borax solution (pH8.2) was used as running buffer. Under the optimum condition, two analytes were base-line separated within 12 min. Excellent linearity was obtained in the concentration range from 2.0×10-6 g/mL ~ 1.0×10-4 g/mL and1.0×10-5 g/mL ~ 1.2×10-4 g/mL for histamine and histidine, respectively. The detection limit was 7.5×10-7 g/mL和5.0×10-6 g/mL for histamine and histidine, respectively. This method was successfully used in the rapid analysis of histamine in soy samples. The average recoveries of 95–103% indicated that the experimental results were satisfactory.In chapter 3, using dansyl chloride (DNS) as a pre-column derivative agent, histamine and histidine were determined by RP-HPLC. The optimum conditions for Determination was optimized with the concentration of the derivative agent, the pH of buffer solution, temperature and time of derivative reaction. Excellent linearity was obtained in the concentration range from 1.0×10-5 g/mL ~ 5.0×10-2 g/mL and1.0×10-5 g/mL ~ 1.0×10-2 g/mL for histamine and histidine, respectively. The detection limit was 1.5×10-6 g/mL和2.5×10-6 g/mL for histamine and histidine, respectively. The analysis of both analytes in soy sauce was satisfactory.