| With the advancement of RP Columns particles technology, based on the Ng or-ganic synthesis and the analysis of synchronous integration technology, the indirect photometric chromatography which is applied in non-conjugated organic anionic compounds analysis possesses the broad application prospects. Traditional inverting indirect photometric chromatography theory is unable to reveal the physical and chemical interaction on the column reactor process. Therefore, the new mechanism of action model needs to be proved. This article provides the nucleophilic addition indi-rect photometric chromatography quantitative analysis method of phosphonic acid (salt) pesticides, the representative varieties of glyphosate and fosetyl-aluminium which is according to the new mechanism and the experimental data. The method is through adding the anion into the sample in order to assess the influence on the sample meas-urement results.On the basic research of IEC-CD and IP-RP-HPLC-ELSD, selected ion-pairing probes reagents diphenylguanidine of effective, easy, cheap, low toxicity and safety by DAD and ELSD dual-channel synchronous monitoring. As well as optimising the RP column, type and concentration of saturated monocarboxylic acid.In time, a new method of IPCna-RP-HPLC-DAD was developed, obtained data of methodology and confirmed qualitative (LC-Q/TOF) and quantitative (IEC-CD). The ion-pairing com-pounds’theoretical values of glyphosate and fosetyl-aluminium are m/z380.1244u and m/z321.1237u respectively. The measured values are m/z380.1316u and m/z321.1307u. The nucleophilic addition on column and covalent ionic reaction of com-pounds was confirmed by two detectors and the delay of10s ELSD signal.According to the a lot of data, the covalent bond compound which contains con-jugated system, the mechanism mode of three-layer-based nucleophilic addition reac-tions is proposed and proved. The stationary phase surface monolayer, the high density of the amide polar group (the first layer) electrostatic attracts the mobile phase a satu-rated monocarboxylic acid anion (the second layer). Due to the influence of the mono-carboxylic acids resonance hybrid body, the diphenylguanidine cations (third layer) against static electricity will adsorb thereon to form a static layer. The measured Au of diphenylguanidine of stationary phase is about14times higher than the concen-tration of mobile phase after balanced. The key of the Ng organic synthesis is the crea-tion of liquid-liquid separation interface to form a non-homogeneous system. This is also the precondition of the application of nucleophilic addition indirect photometric chromatography.The diphenylguanidine as the ion probe reagent, the method of reversed-phase high performance liquid chromatography for analysis of glyphosate content is estab-lished in this experiment. Under the condition of RP8chromatography analysis col-umn, the mobile phase was0.12mmol·L-1diphenylguanidine/2mmol·L-1propi-onic acid aqueous solution, the flow rate was1.2mL·min-1,232nm3D sampling detection, the glyphosate and H2PO4-, NO2-, nitroso glyphosate, Br-, SO42-can be sep-arated. The LOD was10ng. Among the range of5-600mg·L-1glyphosate has clearly linear relationship between the injection mass and the peak area. The linear re-gression equation is Y=-1.20076×105+1.5464×106X, r=0.9996. The level of average recovery for20mg·L-1and200mg·L-1is100.09%-100.86%. The RSD is0.41%through measuring the8parallel samples. This method can be applied for the measurement of glyphosate technical and the isopropylamine salt agent. Due to the high concentration of Cl-in the glyphosate agent, the baseline separation of the both ion compounds was not obtained.Fosetyl-aluminium reversed-phase high performance liquid quantitative analysis method of indirect photometric chromatography is developed through using diphenyl-guanidine as the ion probe reagent. The conditions of the experiment were:RP8chro-matography analysis column, the mobile phase was0.12mmol·L-1diphenylguani-dine/30mmol·L-1acetid acid aqueous solution, a flow rate of1.2mL·min-1232nm3D sampling detection. Fosetyl-aluminium impurity ions and H2PO3-, SO42-can be separated. The LOD10ng with the range of5-600mg·L-1fosetyl-aluminium, the linear regression equation is Y=-5.91067X105+3.2255×103X, r=0.9945. The level of average recovery for20mg. L-1and200mg·L-1is99.85%-99.97%. The RSD is0.77%through measuring the8parallel samples. This method can be used for the measurement of fosetyl-aluminium technical and WP.Due to the reaction between impurity inorganic anions in the sample and miscel-laneous ion probe, the effect should be measured in order to identify the influence of the various concentrations of the inorganic anions on the glyphosate fosetyl-aluminium indirect photometric chromatography results. The experiment results show that when adding Br-≤4.98%, NO2-≤4.31%, H2PO4-≤4.98%, SO42-≤13.04%, Cl-≤0.30%into the glyphosate samples, the glyphosate quantitative results can not be affected. The concentration are Cl-0.14-0.84%, H2PO4-0.16-0.22%, SO42-0.03-0.16%, NO2-0.05-0.08%, Br-0.63%in the glyphosate sample. When the amount of anions is high in the sample, the impurity should be considered primarily. There is no influ-ence on the results when the fosetyl-aluminium samples containing H2PO3-, SO42-≤31.03%. The measured concentrations of H2PO3-, SO42-in the fosetyl-aluminium original drug and WP are5.88-8.49%,4.74-11.22%respectively. Therefore, the influence of these two ions can be ignored.The phosphonic acid (salt) pesticides nucleophilic addition indirect photometric chromatography is simple, rapid, low-cost analysis and environmental compatibility, which also possesses the practical significances on the same type of compound analy-sis. The Ng organic synthesis is significant and of great value to the conventional or-ganic synthesis and the preparation of new organic compounds. |
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