Dissertation > Industrial Technology > Light industry,handicrafts > Food Industry > Fruits, vegetables,nuts processing industry

The Determination of Gibberellic Acid Residue in Vegetable and Fruit

Author HuangHongLin
Tutor ZhangTaoZhi
School Central China Normal University
Course Analytical Chemistry
Keywords Gibberellin Remain Fruit Solid Phase Extraction Gas chromatography - mass spectrometry High Performance Liquid Chromatography Liquid chromatography - mass spectrometry Fluorescence spectroscopy
Type Master's thesis
Year 2004
Downloads 462
Quotes 3
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Gibberellin is a large class of plant hormones, are diterpene, has been isolated and identified more than 100 kinds of gibberellin. Which, especially in the gibberellic acid is the most common, the most important. It is a broad-spectrum plant growth regulator, almost in plant growth, the various stages of development plays a regulatory role, especially for vegetables, fruits, etc. have a significant effect on yield. As macrolide antibiotics, the United States, Japan and other provisions of fruits and vegetables gibberellin maximum residue limits for 0.2ppm. Of gibberellin residue analysis commonly used fluorescence detection technology, the sample pre-treatment commonly used liquid-liquid extraction, TLC separation, column chromatography method. These methods are cumbersome to operate, and the need to use large amounts of organic solvents. This topic is the use of solid-phase extraction (SPE) pre-treatment method, the establishment of a variety of high sensitivity, rapid method of fruit, vegetables Trace gibberellic acid residues were detected, and they are to be compared in order to determine gibberellin The residue standards for basic research. First, the use of solid-phase extraction pretreatment method to purify the sample, investigated the retention behavior of sample C 18 , purification effect is significant. Experiment with the HP-1 column, without pre-column derivatization, direct injection gas chromatography-mass spectrometry (GC-MS) analysis. As selected ion mass spectrometry monitoring of target compounds, can effectively eliminate interference, improve the detection sensitivity of 1 to 2 orders of magnitude, making the analysis of the gibberellin residues in the fruit more simple and feasible. Second, to establish a solid-phase extraction - high performance liquid chromatography (SPE-HPLC) analysis of tomato gibberellin GA 3 residual amount of. Different filler solid phase extraction column extraction recovery of tomato gibberellin, and purification. By comparison: with C 18 column purification, the sample purification solution can be to meet the requirements. Under optimal conditions the C 18 best small column sample extraction effect, solid-phase extraction played a good purification effect, especially for the removal of the sample extract pigments, soluble sugar, acid, ester. The linear range of 0.21 ~ 1.05 × 10 2 mg / L, the detection limit 0.011mg/Kg spiked recoveries ranged from 88.45% to 95.90%, and the RSD was 1.15% to 6.56% . Third, the use of liquid chromatography-mass spectrometry (HPLC-MS) with electrospray ionization (ESI) interface combined with technology, select the ESI negative ion mode, and mass spectrometry gibberellin GA 3 ; and the establishment of tomato gibberellin quantitative determination of the residual method. With conventional liquid chromatography - UV detection the analytical Xin Master Thesis MAS'I 'Bu R'S'1'l! The ESIS wears compare, liquid chromatography-mass spectrometry methods can be discharged to the interference of background impurities having a higher selectivity and sensitivity to simplify the sample extraction step. Electrospray ionization parameters were optimized in the experiment, using multiple reaction monitoring (MRM) quantitative determination of the detection limit of the method 0.02 Oh Kg. The spiked recovery is% .2% to 104.6%, the precision of 4.63% to 6.95%. This method is particularly suitable for complex multi-component mixtures Determination of trace substances, is a determination of plant gibberellin residues in a good way. Fourth, with reference to the People's Republic of China on Import and Export Commodity Inspection industry standard SN 035 Bu 95, using solid phase extraction sample, the use of the gibberellin ethanol solution with concentrated sulfuric acid ligand into a light absorption and can radiate relatively strong radiation fluorescent yellow matrix, thus radiation fluorescence principle, to establish a the Fluorescence Spectrometry grass Xun, oranges gibberellin GA3 residues in. Experiments to optimize the analysis conditions, the sensitivity of the method, but the specificity somewhat less, some impurities after purification by SPE impact on the determination of the GA3 fluorescence value greater determination spike recovery results is less than Chromatography.

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