HPLC的使用步骤.docVIP

高效液相色谱法测定止痛药 By David L. Zellmer and Robert Williams由David L. Zellmer和罗伯特 - 威廉姆斯 (Based on an experiment by Marian Hyman of Texas AM University) （基于由得克萨斯州A＆M大学的玛丽安海曼的实验） April 1997 1997年4月 Version 1.02 (minor additions and corrections), May 2000版本1.02（轻微的补充和修正），2000年5月 The Method该方法 We will use High Performance Liquid Chromatography (HPLC) to separate acetylsalicylic acid, caffeine, and acetaminophen in commercially available pain relievers.我们将使用高效液相色谱法（HPLC）分离市售的止痛药乙酰水杨酸，咖啡因和对乙酰氨基酚。 You must choose a product that has at least two of the above ingredients in it.你必须选择一个产品，至少有两个在它上面的成分。 The package should give you the manufacturers composition.该软件包应该给你制造商组成。 At the conclusion of the analysis you can compare your results with those stated on the package.在分析的结论，你可以比较你的结果，与包装上指明的。 Dont assume that the package is correct.不要以为包是正确的的。 The purpose of the written report is to establish the credibility of your analysis.书面报告的目的是，建立你的分析信誉。 The structures of the compounds we are separating are given below.下面给出我们分离的化合物的结构。 One more compound has been added, Salicylic Acid.一个化合物已增加，水杨酸。 This substance will be our Internal Standard, and will be added in constant amount to all our standard and unknown runs.这种物质将我们的内部标准，将在不断的金额加入到我们所有的标准和未知的运行。 Our chromatographic column will be a 30 cm C-18 column, relatively non-polar in character.我们的色谱柱将是一个30厘米C - 18柱，在性格上比较非极性。 Our mobile phase will be a mixture of water, methanol and acetic acid.我们的流动相，将水，甲醇和醋酸的混合物。 By varying the water-methanol mix we can control the polarity of our solvent.通过不同的水 - 甲醇混合，我们可以控制我们的溶剂的极性。 By varying the acetic acid, we can vary its pH.通过改变醋酸，我们可以改变它的pH值。 Under acid conditions we might expect that one of the nitrogens in acetaminophen or caffeine (both look like they might be weak bases) to pick up a proton and become a highly polar cation, while acetylsalicylic acid and salicylic acid (both weak acids) remain as less polar molecular species.在酸性条件下，我们可以期望，对乙酰氨基酚或咖啡因氮原子（两个看起来像他们可能会弱碱）拿起一个质子和成为一个高度极性的离子，而乙酰水杨酸