Method for determining various organic phosphates in surface water by ultra performance liquid chromatography-mass spectrometry

Abstract

The invention discloses a method for determining various organic phosphates in surface water by ultra performance liquid chromatography-mass spectrometry. The method includes the main steps of (1) preparing a gradient standard mixed working solution; (2) processing a sample before liquid-liquid extraction; (3) determining a standard solution and a sample solution in the ultra performance liquid chromatography-mass spectrometry; (4) obtaining a standard curve of an organophosphate monomer by standard solution test data and obtaining the content of organophosphate ester in the sample through a standard curve of sample liquid test data. The sample preprocessing is simple, the small column clogging problem is effectively solved, and the small column polarity selection range is wide. The 11 kinds of organic phosphates are qualitatively and quantitatively determined by the ultra performance liquid chromatography-mass spectrometry to achieve good separation of all the organic phosphates within 17 minutes. The target blank adding standard recovery rate is 70%-120% (except for triethyl phosphate 63%), and the test limit is 0.08-1.8ng / L.

Description

Technical field [0001] The invention relates to a method for measuring multiple organic phosphates in surface water, in particular to a method for determining multiple organic phosphates in surface water by ultra-high performance liquid chromatography-mass spectrometry. Background technique [0002] Organophosphate esters (OPEs) are a new type of synthetic organic compounds. They are inexpensive and have good compatibility with polymer materials. They are often used as additive flame retardants and plasticizers. Organophosphates can be divided into three categories according to their structures and uses: alkyl-substituted organic phosphates are mainly used as plasticizers, defoamers and additives; halogenated alkyl-substituted and aryl-substituted organic phosphates are mainly used for furniture, Flame retardants for textiles, mattresses, electronic products, and children's related products (baby strollers, pajamas, baby clothing). This type of organic phosphate is persistent, di...

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Problems solved by technology

The risk draft issued by the European Union in 2006 believed that TCEP was carcinogenic, highly toxic and environmentally persistent. In 1998, the World Health Organization's research showed that TDCPP was carcinogenic. TCEP and TDCPP had potential neurotoxicity and acute or chronic toxicity to aquatic organisms. Negative Effects

[0004] Due to the different hydrogen substituting groups of organic phosphates, the physical and chemical properties of different types of substituting groups of organic phosphates are very different, such as polarity, volatility, water solubility, octanol-water partition coefficient, etc. The analysis and detection of the

At present, the pretreatment method of organophosphate in water is mainly solid-phase extraction, which can better extract the target substance in drinking water and underground well water with less impurity interference, but for the impurity interference of rivers More serious water bodies may cause clogging and serious interference from impurities; the polarity retention range of the solid-phase extraction cartridge is limited, and the extraction of more types of organic phosphates cannot be completed; in addition, the extraction and purification in the pretreatment process cannot be performed in one step Completion, complex operation, poor sensitivity and selectivity

[0005] At present, the detection methods of organophosphate mainly include gas chromatography and liquid chromatography. , although the method of GC-NPD has good selectivity to phosphorus-containing compounds, but the stability of the method is poor, and the rubidium beads in the detector need to be replaced regularly; the method of GC-EI-MS can weaken the matrix effect on the quantitative process However, Bjorklund J et al pointed out in the article Rapid Communications in Mass Spectrometry Rcm in 2004 that too many fragments would be generated when GC-MS analysis was applied, especially when analyzing aliphatic triesters, these OPEs would produce 3 McFarland rearrangements , so that the EI-MS spectral signal is quite weak, the base peak is m / z99, which is consistent with the protonated phosphate, so the matrix components will interfere with low-mass ions

Liquid chromatography mainly includes liquid chromatography-mass spectrometry (LC-MS). Compared with GC-MS, the detection of OPEs by this method has higher selectivity and sensitivity, and can directly detect OPEs in water samples without the need for The target is transferred to an organic solvent, and other more polar compounds can be determined simultaneously. However, the currently developed LC-MS method has two defects: one is that there are fewer types of organic phosphates that can be analyzed at the same time, and the other is that The analysis time of the sample is too long, averaging 20 minutes or even 30 minutes, so the extraction-analysis method for OPEs still needs to be continuously improved

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