A metal-organic coordination polymer [Cd2(C6H8N2O2)2Cl4]n·3nH2O [where C6H8N2O2 is ionic liquid,1-carboxymethyl-3-methylimidazolium] 1 has been hydrothermally synthesized and characterized by X-ray diffraction si...A metal-organic coordination polymer [Cd2(C6H8N2O2)2Cl4]n·3nH2O [where C6H8N2O2 is ionic liquid,1-carboxymethyl-3-methylimidazolium] 1 has been hydrothermally synthesized and characterized by X-ray diffraction single-crystal structure analysis.The complex crystallizes in orthorhombic,space group Aba2 with a=1.747 6(3) nm,b=1.933 6(4) nm,c=0.692 75(13) nm,V=2.340 9(8) nm3,Mr=700.96,Dc=1.989 g·cm-3,μ(Mo Kα) =2.312 mm-1,F(000) =1 368,Z=4,the final R=0.021 4 and wR=0.051 2 for 3 331 observed reflections(I>2σ(I) ) .Each Cd(Ⅱ) atom is in a distorted octahedral environment,surrounded by an uncommon symmetrical bidentate chelating carboxylato group and two pairs of bridging chloro ligands.Successive octahedra related by the c-glide of eration share edges to generate a one-dimensional polymeric structure.CCDC:692298.展开更多
建立了一种同时测定化妆品中1-甲基咪唑(1-MEI)、2-甲基咪唑(2-MEI)和4-甲基咪唑(4-MEI)的高效液相色谱-串联质谱(HPLC-MS/MS)方法。样品经乙腈提取、混合型阳离子交换(MCX)固相萃取柱净化、氮吹及复溶后,使用XBridge shield RP 18色谱...建立了一种同时测定化妆品中1-甲基咪唑(1-MEI)、2-甲基咪唑(2-MEI)和4-甲基咪唑(4-MEI)的高效液相色谱-串联质谱(HPLC-MS/MS)方法。样品经乙腈提取、混合型阳离子交换(MCX)固相萃取柱净化、氮吹及复溶后,使用XBridge shield RP 18色谱柱(150 mm×4.6 mm,3.5μm)进行分离;以含0.1%甲酸的20 mmol/L甲酸铵水溶液-乙腈(98∶2,v/v)作为流动相进行等度洗脱;质谱分析采用电喷雾电离(ESI)源和多反应监测(MRM)模式,外标法定量。结果表明,1-MEI在5~200μg/L范围内线性关系良好(相关系数(r^(2))≥0.9994),2-MEI和4-MEI在2~100μg/L范围内线性关系良好(r^(2)≥0.9984)。3种甲基咪唑类化合物的检出限(LOD)为10~30μg/kg,定量限(LOQ)为25~100μg/kg。在低、中、高3个加标水平下,不同空白基质中3种甲基咪唑类化合物的回收率为80.9%~107.9%,相对标准偏差(RSD,n=6)为1.2%~12.8%。将该方法应用于48个化妆品样品的检测,结果表明,有9个样品检出4-MEI,检出含量为26~1000μg/kg;2个样品检出2-MEI,检出含量分别为240μg/kg和267μg/kg;而48个样品中均未检出1-MEI。该方法简单、快速,灵敏度高,为化妆品中3种甲基咪唑类化合物的风险评估和筛查监测提供了技术支撑。展开更多
文摘A metal-organic coordination polymer [Cd2(C6H8N2O2)2Cl4]n·3nH2O [where C6H8N2O2 is ionic liquid,1-carboxymethyl-3-methylimidazolium] 1 has been hydrothermally synthesized and characterized by X-ray diffraction single-crystal structure analysis.The complex crystallizes in orthorhombic,space group Aba2 with a=1.747 6(3) nm,b=1.933 6(4) nm,c=0.692 75(13) nm,V=2.340 9(8) nm3,Mr=700.96,Dc=1.989 g·cm-3,μ(Mo Kα) =2.312 mm-1,F(000) =1 368,Z=4,the final R=0.021 4 and wR=0.051 2 for 3 331 observed reflections(I>2σ(I) ) .Each Cd(Ⅱ) atom is in a distorted octahedral environment,surrounded by an uncommon symmetrical bidentate chelating carboxylato group and two pairs of bridging chloro ligands.Successive octahedra related by the c-glide of eration share edges to generate a one-dimensional polymeric structure.CCDC:692298.
