The Application Of A Fluorescence Derivatization Reagent AOHC In The Analysis Of Low Molecular Mass Aldehydes

Low molecular mass aldehydes(LMMAs)are known for their cytotoxic,aremutagenic and carcinogenic effects.Therefore,it is very important to develop a simple and sensitve detection method for the analysis of LMMAs.However,LMMAs have strong hydrophilicity,high volatility and poor thermal stability,most of which do not have chromophores or fluorophore groups,so that they are normally derivatized before detection.In this thesis,a reductive oxyamination derivatization method was developed by using an aminooxy fluorescent reagent,namely 4-((aminooxy)methyl)-7-hydroxycoumarin(AOHC),as derivative reagent.Based on this method,LMMAs in various samples were determined by high performance liquid chromatography-fluorescence detection(HPLC-FLD).The main work is as follows:(1)The fluorescence properties of fluorescent reagent AOHC were characterized.Reductive oxyamination derivatization method was developed,and the conditions of this method were optimized to achieve highly sensitive and selective analysis for furfural(F),5-methyl furfural(MF)and 5-hydroxymethyl furfural(HMF).The derivatization can be carried out at room temperature,avoiding the artificial generation of HMF at high temperature.Compared with hydrazine lableing methods,our method has high sensitivity and selectivity,avoiding the generation of isomers.Finally,the method has been successfully applied to the determination of furfurals in six kinds of liquors including beer,Chinese liquor,whisky and vodka.The recovery was 94.28-106.60%.(2)Reductive oxyamination method was applied to the determination of aromatic aldehydes.AOHC was used to react with three common aromatic aldehydes,including benzaldehyde(B1),phenylacetaldehyde(B2)and phenylpropanal(B3).After the optimization of several reaction parameters,the derivatization method for aromatic aldehydes analysis was formed.The reaction can happen at 25 ? with short reaction time(15 min).The detection limits were 5-15 nM.The method was then applied to the analysis of two kinds of wine.Finally,two aromatic aldehydes were successfully detected and quantitatively analyzed in the wine samples.(3)12 LMMAs were analyzed by our method using HPLC-FLD.The derivatization method can label 12 aldehydes rapidly at room temperature and produce derivatives with good chromatographic behaviors.By adjusting elution condition,the baseline separation of 12 aldehydes were achieved on an ODS column.Finally,the aldehydes in milk powder were successfully determined with good accuracy and satisfactory reproducibility.