Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have ...Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail.展开更多
建立了一种SN-38脂质体包封率的测定方法。采用SephadexG-50填充微柱,分别使用0.5 mL pH=3.0的磷酸盐缓冲液PBS和Na_(2)CO_(3)-NaHCO_(3)缓冲液(0.2 mol·L^(-1),pH=10.0)洗脱脂质体中的包封药物和游离药物。将收集所得溶液在λ=381...建立了一种SN-38脂质体包封率的测定方法。采用SephadexG-50填充微柱,分别使用0.5 mL pH=3.0的磷酸盐缓冲液PBS和Na_(2)CO_(3)-NaHCO_(3)缓冲液(0.2 mol·L^(-1),pH=10.0)洗脱脂质体中的包封药物和游离药物。将收集所得溶液在λ=381 nm下用紫外分光光度计测定吸光度,并绘制洗脱曲线。筛选出SN-38脂质体包封率测定的最优方案。由洗脱曲线可知,用0.5 mL pH=3.0的PBS洗脱2次,脂质体基本完全被洗脱下来。换用Na_(2)CO_(3)-NaHCO_(3)缓冲液(0.2 mol·L^(-1),pH=10.0)洗脱,在洗脱液体积为12.5 mL时,游离药物被洗脱下来。用紫外分光光度计测定吸光度,代入标准曲线得到溶液的质量浓度,计算脂质体的包封率。经计算,3批SN-38脂质体的平均包封率为92.0%。该方法操作简单方便,重复性好,测定结果准确可靠,可以作为测定SN-38脂质体包封率的有效方法。展开更多
文摘Applying calculation method in alloy design should be an important tendency due to its characters of inexpensive cost, high efficiency and prediction. DOS calculations of AuSn, AsSn and SbSn Sn- based alloys have been investigated by employing DV - Xa method, in which different cluster models were adopted to calculate electron structure.It is proved that some regulations must be taken into ac- count in order to carry out alloy design calculation successfully,which are described in this paper in detail.
文摘建立了一种SN-38脂质体包封率的测定方法。采用SephadexG-50填充微柱,分别使用0.5 mL pH=3.0的磷酸盐缓冲液PBS和Na_(2)CO_(3)-NaHCO_(3)缓冲液(0.2 mol·L^(-1),pH=10.0)洗脱脂质体中的包封药物和游离药物。将收集所得溶液在λ=381 nm下用紫外分光光度计测定吸光度,并绘制洗脱曲线。筛选出SN-38脂质体包封率测定的最优方案。由洗脱曲线可知,用0.5 mL pH=3.0的PBS洗脱2次,脂质体基本完全被洗脱下来。换用Na_(2)CO_(3)-NaHCO_(3)缓冲液(0.2 mol·L^(-1),pH=10.0)洗脱,在洗脱液体积为12.5 mL时,游离药物被洗脱下来。用紫外分光光度计测定吸光度,代入标准曲线得到溶液的质量浓度,计算脂质体的包封率。经计算,3批SN-38脂质体的平均包封率为92.0%。该方法操作简单方便,重复性好,测定结果准确可靠,可以作为测定SN-38脂质体包封率的有效方法。
