固相萃取-超高效液相色谱串联质谱法快速测定猪尿中的赛庚啶

建立了猪尿中赛庚啶的固相萃取-超高效液相色谱串联质谱的测定方法。猪尿样品经酸化,混合型阳离子交换固相柱萃取后,以超高效液相色谱串联质谱测定,外标法定量。本方法的测定线性范围为0.2～5.0μg/L,在0.2、0.4、2.0μg/L低、中、高三个浓度的回收率为80%～120%,批内、批间精密度小于20%。本方法简便、快速、灵敏,经实际样品分析,适用于猪尿中赛庚啶的定量测定和确证。     

高效液相色谱-串联质谱法测定猪肉中盐酸可乐定和盐酸赛庚啶

研究建立了高效液相色谱-串联质谱法测定猪肉中盐酸可乐定和盐酸赛庚啶的方法.样品中的盐酸可乐定和盐酸赛庚啶用0.1mol/L HCl酸化的甲醇提取,过WCX柱,LC-MS/MS进行分析.分析时采用Waters BEH C18色谱柱(100 mm×2.1mm,1.7μm),以0.10％甲酸水-甲醇作为流动相进行梯度洗脱,电喷雾正电子(ESI+)模式电离,多反应监测(MRM)模式检测,外标法进行定量.结果表明,盐酸可乐定和盐酸赛庚啶标准溶液在1.0～50.0 μg/L范围内,峰面积与含量呈线性相关.盐酸可乐定和盐酸赛庚啶的检出限均为0.20 μg/kg,样品中添标回收率在85％ ～ 100％,相对标准偏差(RSD)小于10％.     

ELISA试剂盒用于检测猪尿中赛庚啶残留的考察

对市场销售的四种未明确标识可用于猪尿样品的赛庚啶ELISA试剂盒进行考察,使用空白猪尿和不同浓度的空白添加猪尿对其反应原理、可操作性、灵敏度、检测限、回收率等进行研究,发现其中三种赛庚啶ELISA试剂盒可用于猪尿中赛庚啶残留检测,但需根据试剂盒的特点按需选择。结果表明使用市售的ELISA试剂盒监测猪尿中赛庚啶残留简便可靠,可作为初筛方法,检坝0限为0．5μg／L。     

超高效液相色谱－串联质谱法检测饲料中盐酸可乐定和盐酸赛庚啶

建立了检测饲料中盐酸可乐定和盐酸赛庚啶的超高效液相色谱-串联质谱（UPLC/MS/MS）分析方法。样品经酸性甲醇提取,浓缩后用乙腈-0.2%甲酸溶解,经超高效液相色谱-串联质谱在多反应检测（MRM）模式下测定。结果显示盐酸可乐定和盐酸赛庚啶标准曲线在0.2～50μg/L浓度范围内线性良好。线性相关系数（r）分别为0.999 4和0.999 2;在0.02～1.0 mg/kg添加水平下,盐酸可乐定和盐酸赛庚啶的加标回收率在70%～110%,相对标准偏差（RSD）均小于10%（n=6）;本方法对动物饲料中盐酸可乐定和盐酸赛庚啶的定量限为0.02 mg/kg（S/N〉10）,检出限为0.01 mg/kg（S/N〉3）。     

Antagonistic effects of cyproheptadine and anisodamine on [Ca2+]i elevation induced by TNFα in endothelial cell strains

AIM: To study the effects of cyproheptadine (Cyp) and anisodamine (Ani) on the changes of intracellular free Ca²⁺ concentration ([Ca²⁺]_i) induced by tumor necrosis factor (TNFα) in single endothelial cells, and to explore the mechanisms of TNFα mediated shock and antishock actions of Cyp and Ani. METHODS: Human umbilical vein endothelial cell strains (ECV304) were seed in 35 mm tissue culture dish with 2 mL DMEM culture medium. The cultured cells were loaded by Fluo-3/AM. The spatial distribution and the dynamic changes of [Ca²⁺]_i in single endothelial cell was determined by laser scanning confocal microscopy (LSCM). RESULTS: [Ca²⁺]_i in single endothelial cell after stimulation of TNFα rapidly increased in a dose-dependent manner and approached the peak value within 60 seconds, afterwards, decreased and kept above the basal level. The confocal scanning image showed that [Ca²⁺]_i elevation was more obvious in nuclear than in cytoplasma, and decreased slowly. Cyp (3×10^-5, 6×10^-5 mol/L) and Ani (2×10^-5, 4×10^-5 mol·L^-1) markedly inhibited TNFα (1.2×10^-9 mol·L^-1)-induced [Ca²⁺]_i elevation. CONCLUSIONS: TNFα markedly induces elevation of [Ca²⁺]_i in single endothelial cell, it may be an important mechanism of TNFα-induced shock and tissue injury. Cyp and Ani obviously suppress TNFα-induced [Ca²⁺]_i elevation, which probably is one of the mechanisms of their antishock effects.