yongzhbenq
第89楼2010/07/27
前面讲了一些欧洲药典的规定,后面可以再看看美国药典的规定
Adjustments to the Chromatographic System
As mentioned, <621> allows a number of adjustments to the chromatographic system in response to issues with a procedure's system suitability. These are the maximum allowable variations unless the individual monograph directs otherwise.
Ratio of components in mobile phase: Although the replacement of any solvent in the mobile phase constitutes a change and not an adjustment, the amounts of the minor components (specified as 50% or less) in the mobile phase can be adjusted up to ±30% relative to the particular component. However, the change in any component cannot exceed ±10% absolute (that is, in relation to the total mobile phase). Adjustments can be made to one minor component in a ternary mixture.
pH of mobile phase: The pH of the aqueous buffer used in the preparation of the mobile phase can be adjusted to within ±0.2 units of the value or range specified.
Column temperature: The column temperature can be adjusted by as much as ±10 °C.
Concentration of salts in buffer: The concentration of the salts used in the preparation of the aqueous buffer for the mobile phase can be adjusted up to ±10% relative to the particular component, provided the permitted pH variation (see above) is met.
Wavelength of UV–vis detector: Deviations from the wavelengths specified in the method are not permitted.
Stationary phase:
plexu
第97楼2010/07/27
问题有些多,先回答前2个。
色谱技术中的化学衍生法系指在色谱过程中用特殊的化学试剂(一般称为衍生化试剂或标记试剂)使样品成分转变相应的衍生物之后进行分离检测或进行检测的方法。目的为:1.将紫外—可见强吸收功能基团引入被检测对象或将其转变为荧光衍生物,以提高检测灵敏度;2提高对分析样品的分离和选择性。
从是否与HPLC系统联机的角度,化学衍生法分为在线on line)与离线∣Off line)两种。从发生衍生化的场合,分为柱前衍生法pre-column derivatization)与柱后衍生法(post-column derivatization)两种。目前,在HPLC中,以离线的柱前衍生法(简称柱前衍生法)与在线的柱后衍生法(简称柱后衍生法)使用居多。