Molecularly imprinted polymers(MIPs) were synthesized by using derivatives of benzoic acid and ethyl benzoate as the templates. The paper aims at studying the effect of the different functional groups on the imprintin...Molecularly imprinted polymers(MIPs) were synthesized by using derivatives of benzoic acid and ethyl benzoate as the templates. The paper aims at studying the effect of the different functional groups on the imprinting process by summarizing the chromatographic data,and the relationship between the imprinting interaction and the solvents used during the polymerization was discussed. The experimental results show that the structure of the template plays a decisive role in imprinting effect,and imprintogenicity can be improved by changing solvent and monomer for the template. In addition,when carboxy group is replaced by ester group,the templates would lose their imprinting effect completely in acetonitrile;if chloroform is used as porogen,the imprintogenicity of ethyl p-aminobenzoate and ethyl p-hydroxybenzoate will evidently be improved. The result indicates that the solvents used during the polymerization have a great influence on whether the groups of the template can act as effective imprinting groups. Therefore,the solvents should be taken into account in designing the experiments or in theoretical prediction of the imprinting effect of the templates. [WT5HZ]展开更多
建立了测定动物饲料中三唑仑、艾司唑仑、硝西泮、地西泮、异丙嗪、氯氮平、唑吡坦、甲硫哒嗪、氯丙嗪和咪达唑仑10种违禁精神药物的超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF-MS)方法。样品经混合溶剂甲醇-0.1 mo l/L HCl(9∶1,v...建立了测定动物饲料中三唑仑、艾司唑仑、硝西泮、地西泮、异丙嗪、氯氮平、唑吡坦、甲硫哒嗪、氯丙嗪和咪达唑仑10种违禁精神药物的超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF-MS)方法。样品经混合溶剂甲醇-0.1 mo l/L HCl(9∶1,v/v)振荡提取,再用MCX固相萃取柱净化处理后,采用UPLC-Q-TOF-MS分析检测。10种化合物在5～100μg/L范围内均呈良好的线性关系,线性相关系数均大于0.99。本方法的硝西泮、唑吡坦和甲硫哒嗪的定量限(LOQ,以信噪比为10计)为8μg/kg,三唑仑、艾司唑仑、地西泮、异丙嗪、氯丙嗪和咪达唑仑为10μg/kg,氯氮平为20μg/kg。3个添加水平(LOQ、2LOQ、4LOQ)的回收率试验结果表明,10种化合物的回收率在60.6%～108.5%范围内,相对标准偏差均小于10%。本方法可用于动物饲料中违禁精神药物的准确测定。展开更多
目的建立超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(ultraperformanceliquid chromatography-quadrupole-orbitrap high resolution mass spectrometry,UPLC-Q-OrbitrapHRMS)结合化学计量学鉴别新鲜和反复冻融牛肉的分析方法。...目的建立超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(ultraperformanceliquid chromatography-quadrupole-orbitrap high resolution mass spectrometry,UPLC-Q-OrbitrapHRMS)结合化学计量学鉴别新鲜和反复冻融牛肉的分析方法。方法样本经过前处理后,采用UPLC-Q-OrbitrapHRMS获得新鲜和反复冻融牛肉指纹图谱信息。运用SIMCA软件结合模式识别方法对数据进行分析,建立新鲜和反复冻融牛肉的主成分分析(principal component analysis,PCA)模型和正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)模型。结果PCA模型选择了前10个主要成分,解释了总方差(R2)的70.9%,其预测能力(Q2)为52.1%,结果表明PCA模型可以对新鲜和反复冻融牛肉进行有效区分。OPLS-DA模型中的R2、Q2均接近于1,说明模型的预测能力及准确性较好。采用变量重要性因子(variable importance factor,VIP)筛选出冻融过程中11种可能的差异代谢物,进一步进行结构确证,确定了乳酸、烟酸和酪胺为生物标志物。结论UPLC-Q-Orbitrap HRMS结合化学计量学的方法可以用于新鲜和反复冻融牛肉的有效鉴别。展开更多
文摘Molecularly imprinted polymers(MIPs) were synthesized by using derivatives of benzoic acid and ethyl benzoate as the templates. The paper aims at studying the effect of the different functional groups on the imprinting process by summarizing the chromatographic data,and the relationship between the imprinting interaction and the solvents used during the polymerization was discussed. The experimental results show that the structure of the template plays a decisive role in imprinting effect,and imprintogenicity can be improved by changing solvent and monomer for the template. In addition,when carboxy group is replaced by ester group,the templates would lose their imprinting effect completely in acetonitrile;if chloroform is used as porogen,the imprintogenicity of ethyl p-aminobenzoate and ethyl p-hydroxybenzoate will evidently be improved. The result indicates that the solvents used during the polymerization have a great influence on whether the groups of the template can act as effective imprinting groups. Therefore,the solvents should be taken into account in designing the experiments or in theoretical prediction of the imprinting effect of the templates. [WT5HZ]
文摘建立了测定动物饲料中三唑仑、艾司唑仑、硝西泮、地西泮、异丙嗪、氯氮平、唑吡坦、甲硫哒嗪、氯丙嗪和咪达唑仑10种违禁精神药物的超高效液相色谱-四极杆飞行时间质谱(UPLC-Q-TOF-MS)方法。样品经混合溶剂甲醇-0.1 mo l/L HCl(9∶1,v/v)振荡提取,再用MCX固相萃取柱净化处理后,采用UPLC-Q-TOF-MS分析检测。10种化合物在5～100μg/L范围内均呈良好的线性关系,线性相关系数均大于0.99。本方法的硝西泮、唑吡坦和甲硫哒嗪的定量限(LOQ,以信噪比为10计)为8μg/kg,三唑仑、艾司唑仑、地西泮、异丙嗪、氯丙嗪和咪达唑仑为10μg/kg,氯氮平为20μg/kg。3个添加水平(LOQ、2LOQ、4LOQ)的回收率试验结果表明,10种化合物的回收率在60.6%～108.5%范围内,相对标准偏差均小于10%。本方法可用于动物饲料中违禁精神药物的准确测定。
文摘目的建立超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(ultraperformanceliquid chromatography-quadrupole-orbitrap high resolution mass spectrometry,UPLC-Q-OrbitrapHRMS)结合化学计量学鉴别新鲜和反复冻融牛肉的分析方法。方法样本经过前处理后,采用UPLC-Q-OrbitrapHRMS获得新鲜和反复冻融牛肉指纹图谱信息。运用SIMCA软件结合模式识别方法对数据进行分析,建立新鲜和反复冻融牛肉的主成分分析(principal component analysis,PCA)模型和正交偏最小二乘-判别分析(orthogonal partial least squares-discriminant analysis,OPLS-DA)模型。结果PCA模型选择了前10个主要成分,解释了总方差(R2)的70.9%,其预测能力(Q2)为52.1%,结果表明PCA模型可以对新鲜和反复冻融牛肉进行有效区分。OPLS-DA模型中的R2、Q2均接近于1,说明模型的预测能力及准确性较好。采用变量重要性因子(variable importance factor,VIP)筛选出冻融过程中11种可能的差异代谢物,进一步进行结构确证,确定了乳酸、烟酸和酪胺为生物标志物。结论UPLC-Q-Orbitrap HRMS结合化学计量学的方法可以用于新鲜和反复冻融牛肉的有效鉴别。
