对枯草芽胞杆菌B6-1的去细胞发酵液进行超滤(分子量截留6-8kD),取截留液用6 N HCl酸沉淀,沉淀再经氯仿/甲醇(2∶1)和甲醇依次抽提,ODS-C18柱固相萃取,用不同浓度的甲醇水溶液依次梯度洗脱,活性最强的70%、80%、100%甲醇溶液合并。经LC-M...对枯草芽胞杆菌B6-1的去细胞发酵液进行超滤(分子量截留6-8kD),取截留液用6 N HCl酸沉淀,沉淀再经氯仿/甲醇(2∶1)和甲醇依次抽提,ODS-C18柱固相萃取,用不同浓度的甲醇水溶液依次梯度洗脱,活性最强的70%、80%、100%甲醇溶液合并。经LC-MS分析,得出这些物质属于脂肽类表面活性剂抗生素,部分分子量(1450、1464、1478、1506)与已经报道的C15、C16、C17、C19脂肽fengycins相吻合。展开更多
应用超高效液相色谱-串联质谱法测定了助眠类保健品中22种禁用安神类药物的含量。将样品连同其包衣和胶囊壳一起研碎后称取1.000g样品用甲醇溶解,经涡旋混匀并超声15min,用甲醇定容至25.0mL。离心后取上清液5.00mL,经Oasis PRiME HLB固...应用超高效液相色谱-串联质谱法测定了助眠类保健品中22种禁用安神类药物的含量。将样品连同其包衣和胶囊壳一起研碎后称取1.000g样品用甲醇溶解,经涡旋混匀并超声15min,用甲醇定容至25.0mL。离心后取上清液5.00mL,经Oasis PRiME HLB固相萃取柱净化处理,收集经净化的流出液,与用于淋洗固相萃取柱的甲醇2mL合并,于40℃下吹氮至溶液近干。用体积比为1∶1的0.05%(体积分数,下同)甲酸-甲醇混合溶液1.00mL溶解残渣,所得溶液经过0.22μm滤膜过滤,滤液供色谱分离。选用Poroshell 120EC-C18色谱柱(50mm×3.0mm,2.7μm)作为固定相,用不同比例的(A)含0.05%甲酸的5mmol·L^-1乙酸铵溶液和(B)乙腈的混合溶液作为流动相按程序进行梯度洗脱。质谱测定中采用电喷雾离子源和多反应监测模式。结果表明:22种禁用安神类药物的标准曲线中有17种线性范围为4~800μg·L^-1,有1种为40~8 000μg·L^-1,还有4种为400~80 000μg·L^-1,其检出限(3S/N)为0.02~2μg·g-1。用标准加入法进行回收试验,测得回收率为81.2%~98.9%,测定值的相对标准偏差(n=6)为3.1%~9.7%。展开更多
Based on solid phase extraction method, a novel silicon-PDMS-glass microchip for high purity DNA extraction has been developed by using KI as the binding salt. The microfluidic chip fabricated by MEMS technology was c...Based on solid phase extraction method, a novel silicon-PDMS-glass microchip for high purity DNA extraction has been developed by using KI as the binding salt. The microfluidic chip fabricated by MEMS technology was composed of a silicon substrate with a coiled channel and a compounded PDMS-glass cover. With this microfluidic chip, the wall of the coiled channel was used as solid phase matrix for binding DNA and DNA was extracted by the fluxion of the binding buffer, washing buffer and elution buffer. KI as a substitute for guanidine, was used successfully as binding salt for purification DNA, obtaining higher purity of genomic DNA and about 13.9 ng DNA from 1 μL rat whole blood in 35 minutes.展开更多
文摘对枯草芽胞杆菌B6-1的去细胞发酵液进行超滤(分子量截留6-8kD),取截留液用6 N HCl酸沉淀,沉淀再经氯仿/甲醇(2∶1)和甲醇依次抽提,ODS-C18柱固相萃取,用不同浓度的甲醇水溶液依次梯度洗脱,活性最强的70%、80%、100%甲醇溶液合并。经LC-MS分析,得出这些物质属于脂肽类表面活性剂抗生素,部分分子量(1450、1464、1478、1506)与已经报道的C15、C16、C17、C19脂肽fengycins相吻合。
基金the financial support from the National Natural Science Foundation of China(No.20299030,60427001 and 60501020).
文摘Based on solid phase extraction method, a novel silicon-PDMS-glass microchip for high purity DNA extraction has been developed by using KI as the binding salt. The microfluidic chip fabricated by MEMS technology was composed of a silicon substrate with a coiled channel and a compounded PDMS-glass cover. With this microfluidic chip, the wall of the coiled channel was used as solid phase matrix for binding DNA and DNA was extracted by the fluxion of the binding buffer, washing buffer and elution buffer. KI as a substitute for guanidine, was used successfully as binding salt for purification DNA, obtaining higher purity of genomic DNA and about 13.9 ng DNA from 1 μL rat whole blood in 35 minutes.
