----------广告结束,我是分割线------------------- 借此广告机会,路人丙再次为断更道歉,为表诚意,奉上800字,中西合璧彩蛋一枚。中英双语哦,路人丙一个字一个字敲进去的哦,检查了三遍哦,放心看哦。 大家可以藉此感受一下大师的风采,比起路人丙,那是不知道高到哪里去了。相信有一天,我们之中,有人可以和他们谈笑风生。 第5章 色谱柱 5.1 引言 色谱柱是HPLC分离过程的核心。一支稳定、高效的色谱柱对建立普适性强、重现性好的方法是必不可少的。不同供应商的色谱柱,甚至来源相同、认为完全一样的色谱柱之间,可能也会存在很大差异,尤其是不同的色谱柱在塔板数、谱峰的对称性、保留值、峰间距以及使用寿命方面会有所不同,而这些不同对建立理想的HPLC方法会产生很大影响。本章中,我们将提供一些有关色谱柱担体、固定相及柱填料的信息供读者参考;讨论色谱柱应用中的问题,以及适宜的解决方案,以确保方法普适性强、重现性好,同时也讨论了在常规HPLC分析中,为获得最佳结果,一支“好”色谱柱的重要意义。 选择HPLC柱时,大多数使用者都认为柱间的重现性是方法建立中极为重要的因素。色谱工作者不愿在校准了一具体系统后,又不得不为一新色谱柱再重新建立HPLC方法。一些生产厂能在一定程度上保证柱性能指标的重现性,如色谱柱塔板数(N),特定样品与条件下的选择性,反压(压力降),特定测试溶质的保留值(k)。因此,对许多使用者来说,生产优质产品的厂家的信誉很重要。价格对一些用户是重要的因素,但上述讨论的其他因素在建立一个普适性强、令人满意的方法时往往更加重要。色谱柱价格在建立和应用普适性强、可靠的HPLC方法的整个费用中,仅占一小部分(见5.3节)。 参考文献: 张玉奎,王杰,张维冰 译. 实用高效液相色谱法的建立. 华文出版社,2001,185 5 THE COLUMN 5.1 INTRODUCTION The column is the heart of HPLC separation processes. The availability of a stable, high-performance column is essential in developing a rugged, reproducible method. Commercial columns can differ widely among suppliers, and even between supposedly identical columns from a single source. Such differences can have a serious impact on developing the desired HPLC method. Specifically, different columns can vary in plate number, band symmetry, retention, band spacing, and lifetime. In this chapter we give information about various column supports, stationary phases, and column packings. Problems in the use of columns are discussed, with appropriate remedies to ensure rugged, reproducible methods. We also consider the role of “good” columns in optimizing a routine HPLC procedure for best results. When selecting an HPLC column, most users consider column-to-column reproducibility as very important when developing a method. Chromatographers dislike having to redevelop HPLC methods for a new column after they standardize on a particular system. Several manufactures guarantee the reproducibility of certain column performance criteria, such as column plate number (N), selectivity for certain samples and conditions, backpressure (pressure drop), and retention (k) values for specified test solutes. Therefore, the reputation of the manufacturer for producing superior products is important to many users. Price is an important factor to some, but the other factors discussed above usually are more important in developing a rugged, satisfactory method. Column cost is only a small part of the total expense in developing and using a rugged, dependable HPLC method (see Section 5.3). References Lloyd R. Snyder,Joseph J. Kirkland,Joseph L. Glajch. Practical HPLC Method Development 2nd. John Wiley & Sons, Inc. 1997, 175 摘录自博纳艾杰尔