硫酸二甲酯是一种重要的化工原料,广泛应用于药物的合成,染料,香料,和杀虫剂。药品中的高毒性和腐蚀性硫酸二甲酯残留物对人体有害,因此,应严格控制残留物水平。传统的检测方法采用高纯乙腈和无水物作为溶剂,这限制了检测溶剂的选择,降低了检测的通用性和准确性。因此,迫切需要一种简单而准确的方法来测定硫酸二甲酯的残留量。硫酸二甲酯通常采用超高效液相色谱-串联质谱(UHPLC-MS/MS)检测,以吡啶为甲基化底物。在这项研究中,建立了以氨基比林等叔胺检测硫酸二甲酯的新方法,它比吡啶有很多优点,作为甲基化底物。例如,N原子的混合轨道和电子云是不同的,导致更强的亲核性的氨基比林。使用氨基比林时,不需要高温对硫酸二甲酯的稳定性有害,脂肪族季铵盐产品更稳定,具有良好的稳定性,低干扰,良好的电离性能,高反应。分离是在WatersAtlantisHILICC18色谱柱(100mm×2.1mm,3.0μm),使用由10mmol/L乙酸铵溶液-0.1%甲酸甲醇溶液(50∶50,v/v)组成的流动相,流速为0.3mL/min。柱温设定为40℃,样品大小为1μL。在电喷雾正电离(ESI+)和多反应监测(MRM)模式下测定硫酸二甲酯。硫酸二甲酯在0.9935~7.9480ng/mL范围内呈良好的线性关系(r=0.9997)。硫酸二甲酯的检测限和定量限分别为0.50ng/mL和1.15ng/mL,分别。硫酸二甲酯的回收率(n=3)为94.9%~106.4%。相对标准偏差(RSD)为1.44%~5.51%。甲基化氨基比林酮峰面积的RSD为4.32%,表明反应产物具有良好的稳定性。9批氨基比林均未检出硫酸二甲酯基因毒性杂质,咖啡因,和替加氟样品,这表明药品制造商注意控制这些杂质。所提出的方法在更好的离子峰形状和更高的分子量方面优于现有技术。没有其他碎片的干扰。该方法是具体的,敏感,简单,快速,准确,可用于氨基比林等药品中硫酸二甲酯基因毒性杂质的测定。
Dimethyl sulfate is an important chemical raw material that is widely used in the synthesis of drugs, dyes, spices, and pesticides. The highly toxic and corrosive dimethyl sulfate residue in medicines is harmful to the human body, and hence, the residue level should be strictly controlled. Traditional detection methods use high-purity acetonitrile and anhydrous as the solvents, which limits the choice of detection solvents and degrades the versatility and accuracy of detection. Therefore, a simple and accurate method for the determination of dimethyl sulfate residues is urgently needed. Dimethyl sulfate is usually detected by ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) with pyridine as the methylation substrate. In this study, a new method for the detection of dimethyl sulfate was established using tertiary amines such as aminophenazone, which has many advantages over pyridine, as the methylation substrate. For example, the hybrid orbital and electron cloud of the N atom are different, resulting in stronger nucleophilicity of aminophenazone. High temperatures that are detrimental to the stability of dimethyl sulfate are not required when using aminophenazone, and the aliphatic quaternary ammonium salt product is more stable, with good stability, low interference, good ionization properties, and high response. The separation was performed on a Waters Atlantis HILIC C18 column (100 mm×2.1 mm, 3.0 μm) using a mobile phase consisting of 10 mmol/L ammonium acetate solution-0.1% formic acid methanol solution (50∶50, v/v) at a flow rate of 0.3 mL/min. The column temperature was set at 40 ℃, and the sample size was 1 μL. Dimethyl sulfate was determined in the electrospray positive ionization (ESI+) and multiple reaction monitoring (MRM) modes. Dimethyl sulfate showed good linear relationships within the range of 0.9935 to 7.9480 ng/mL (r=0.9997). The limit of detection and limit of quantification for dimethyl sulfate were 0.50 ng/mL and 1.15 ng/mL, respectively. The recoveries (n=3)of dimethyl sulfate were 94.9% to 106.4%. The relative standard deviations (RSDs) were 1.44% to 5.51%. The RSD of the methylated aminophenazone peak area was 4.32%, indicating good stability of the reaction product. Dimethyl sulfate genotoxic impurities were not detected in 9 batches of aminophenazone, caffeine, and tegafur samples, which indicated that the drug manufacturers paid attention to the control of these impurities. The proposed method is advantageous over the existing techniques in terms of the better ion peak shape and higher molecular weight, without interference from other fragments. The method is specific, sensitive, simple, rapid, and accurate, and it can be used for the determination of dimethyl sulfate genotoxic impurities in aminophenazone and other medicines.