前面我们所学的凝胶过滤法、离子交换法以及电泳等一系列分离纯化生物大分子的 手段，比起早期采用的盐析法，有机溶剂及等电点沉淀法等，分离效果要好得多。但是， 这些方法中，或是利用生物大分子在一定条件下不同的溶解度、电荷分布、总电荷的不 同，或是依据其分子的大小和形状的不同。一句话，多是利用生物分子间物理和化学性 质的差异来进行分离纯化的。由于这些方法的特异性比较低，加之待分离物质之间的物 化性质差异较小，常常要综合不同的分离方法。经过许多步骤才能使生物分子达到一定 的纯度

1.了解提纯固体有机化合物的常用方法 2.掌握重结晶方法来提纯固体有机化合物

1. 本实验是一个多步骤综合性实验，也是一个密切 联系生产实际的实验，每步实验得到的产品，又是 下一步合成的原料。通过本实验旨在训练学生综合 运用所学知识解决实际问题的能力，并且培养同学 们的绿色化学理念，启迪学生的创新思维

从固态到气态,然后直接回到固态。此纯化技巧既漂亮又实用 的。找出此影片中为什么用大气压力来升华二茂铁(Ferrocene) From solid to gas, and then straight back to solid. This purification technique is both beautiful and useful. Find out why by watching the atmospheric pressure sublimation of ferrocene in this video

薄层分析法在许多研究实业室是最常用的此影片将带领你每 步骤,从准备跑瓶到计算RF(retention factor)值 步骤, Thin-layer chromatography is the most commonly used analytical technique in many research labs. This video walks you through every step from setting up a developing chamber to calculating Rf values

再结晶须有耐心,但它是值得的!此影片让你用一种溶剂与两种 溶剂的再结晶方法从溶解度测试到冷过滤来经验此过程 Recrystallization takes patience, but it's worth it! This video walks you through the procedure, from solubility tests to cold filtration, with information on one-solvent and two-solvent recrystallizations

萃取、冲洗和干燥:还没到结束不能算结束。藉由分液漏斗示 。 范液相-液相萃取并学习如何用”反应检查步骤”检查你的反应。这 是一个你不会想错失的一个纯化技巧! Extracting, Washing and Drying: It ain't over 'til it's over. Learn how to \work up\ your reaction using a separatory funnel to perform a liquid-liquid extraction. This is one purification technique you don't want to miss!

将液体从固体中分开来的最简易方法是什么?过滤在此影片中 将学习如何有效的用重力过露及真空过滤来进行。 The easiest way to separate a liquid from a solid? Filtration! Learn how to effectively carry out gravity and vacuum filtrations in this video

Working on a vacuum manifold: See LLP chapter 9.2 for an excellent discussion on working with air-sensitive reagents, including how to use a two-way manifold. De-gassing solvents: The best way to remove water and oxygen from a solvent is to distill it over an appropriate drying agent (such as sodium). This can sometimes be a lengthy (and dangerous)task. Since we

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