The Determination Of3-chloro-1,2-propanediol By HPLC-FLD And Synthesis And Evaluation Of Its Pretreatment Materials

3-chloro-1,2-propanediol (3-MCPD), as the representative substance of chloropropan-ol pollutants, has aroused substantial attentions from scholars both at home and abroad dueto its high content and significant biological toxicity. The compositions of food samplesalways are complicated and the content of3-MCPD was very few. Current detectionmeans are mainly confined to GC, GC/MS, GC/MS/MS, which are tedious in processingand expensive in cost. With the increasingly control of3-MCPD’s residual amount,current detection technology can not meet this trend. Therefore, there is a urgent need todevelop effective pretreatment methods, which can be used to realize the3-MCPD’srapidly and efficiently enrichment, increasing the content of3-MCPD in the samples atthe most extent. Cooperated with precision testing instrument, these pretreat-ment methodscan meet the need of3-MCPD’s sensitive detection.This paper has conducted research to the solid phase extraction（SPE）and themagnetic extraction.3-Aminophenylboronic acid/SiO2(APBA/SiO2) as SPE material and3-Aminophenylboronic acid nano particles as magnetic extraction material have beensuccessfully synthesised,their performances had been tested. This article also established anovel approach to determine3-MCPD quantificationally which coupling2-Aminoquinoxa-line as derivatization reagent with HPLC-FLD.Parameters in derivatization have beenoptimized. Three kinds of environmental water samples and five kinds of commerciallyavailable oil samples were randomly chose for the3-MCPD content detection by this newestablished HPLC-FID method.Main conclusions are as follows:(1) The solid phase extraction columns filled with APBA/SiO2particles whichsynthesized through chemical polymerization were successfully made. The APBA/SiO2particles were characterised by scanning electron microscope and Fourier infrared spectr-um scanning.The results showed that they were irregularly shaped particles whichdiameter size raged from20to50microns. Fourier infrared spectrum scanning resultsshowed the particles had characteristic peaks both of APBA and silica gel. Selectiveadsorption performance of the SPE columns was tested by mixture of resorcinol andcatechol.It showed that columns has a good selective adsorption for catechol, and theresults of preliminary optimization experiment told that when the pH value of the balancebuffer was9.0, the methanol concentration of drench lotion was50%, the elution volumewas4ml, the enrichment effect was best, reached more than4.5times.3-MCPD was enriched through this SPE column and the eluant was detected by DFG method combinedwith GC/MS.The result showed that this APBA/SiO2SPE column had a selectiveadsorption for3-MCPD with concentration ratio of3.48.(2) A novel magnetic poly-3-aminophenylboronic acid nanoparticles has been facilesynthesized with chemical oxidation method by using ammonium persulfate (APS) asoxidant, the obtained nanoparticles have been characterized by SEM, FTIR, TGA, XRD;their magnetic properties have been evaluated with MPMS and their selective adsorptionperformance was evaluated with mixture of resorcinol and catechol. The results showedthat the nanoparticles have inverse spinel structure, average diameter of about50nm, andgood paramagnetic properties with saturation magnetization of53.31emu/g. Fourierinfrared spectrum scanning showed it had the particles had characteristic peaks both ofAPBA and Fe3O4. The adsorption test told that the particles had selective adsorption forcatechol with saturated adsorption (Qmax) of10.56mg/g.(3)3-MCPD was decomposed under the oxidation of NaIO4. The oxidized productreacted with the derivatization reagent2-Aminoquinoxaline and then product a epipolicsubstance,which can be well separated from other interfering substances on high perform-ance liquid chromatography (HPLC). With the separating degree(Rs) as an index, theoptimal flow rate chose for HPLC-UV detection was0.6mL/min, the volume rate for Tris–HCl and methanol was0.36:0.24(V/V). The excitation and emission wavelength obtain-ed from fluorescence scanning of the derivative product were λEx=318nm and λEm=367nm. The derivative product’s structure was further verified by MS analysis. Analyzing thesolutions chloroacetaldehyde,2-Aminoquinoxaline, glycerol,1,2-propylene glycol and3-MCPD after fluorescent derivatization, we saw that only the solutions derived by3-MCPD and chloroacetaldehyde obtained the chromatographic target peak at about21min.Other three solutions only product a small interferential peak at the location oftarget peak, so HPLC-FLD method we established had a good selectivity.(4)Optimal conditions of derivatization determined through the single-factorexperiment were as follows, the concentration of Pb (NO3)2for clearing away excessiveoxidant was275mM; the pH value of derivatization reaction was4.0; the volume ratio for2-Aminoquinoxaline and3-MCPD was1:1; the concentration of2-Aminoquinoxalinewas8mg/mL; the reaction temperature and time of derivatization were80℃and3h.Based on these reaction conditions,3-MCPD standard curves respectively under the purewater system and0.01g/mLNaCl system were draw and the curvilinear equation obtainedrespectively were Y=46300.49+55310.69X, R2=0.9971(under pure water system), Y=31937.941X+1.17164*106, R2=0.9908(under0.01g/mLNaCl system). The linearityof these two standard curves were good, the contents detection of3-MCPD in samples as water and oil could refer to them.(5) Randomly choosing three kinds of water samples(Yangtze river water, Eastlake water and waste water from one paper mill in Wuhan) and5kinds of market oilsamples (soybean oil, rice oil, peanut oil, rapeseed oil and camellia oil), the establishedmethod combined2-Aminoquinoxaline with HPLC-FLD to quantificationally detect thecontent of3–MCPD was applied. Detection results showed that the3-MCPD contentsin Changjiang river, East lake and waste water from one paper mill of Wuhan were252.52μg/kg,35.63μg/kg and37.44μg/kg; contents in soybean oil, rice oil, peanut oil, rapeseedoil and camellia oil were about17.91μg/kg、38.68μg/kg、86.15μg/kg、89.55μg/kg and527.76μg/kg.