All calibration standards contain not only ketoprofen (the analyte), but also uracil as an additive. Our solvent system will be slightly acidic (acetonitrile:water 70:30 plus 0.1 % formic acid) and we will use a reverse-phase column. Which of the two compounds will elute first? Ketoprofen (image: https://webbook.nist.gov/) Uracil (image: https://webbook.nist.gov/)单项选择题

题目图片
A

a. Ketoprofen

B

b. Uracil

C

c. Both will elute at the same time

D

d. Neither will elute in the sample time

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All calibration standards contain not only ketoprofen (the analyte), but also uracil as an additive.所有校准标准不仅含有酮洛芬（分析物），还含有尿嘧啶作为添加剂。 Our solvent system will be slightly acidic (acetonitrile:water 70:30 plus 0.1 % formic acid) and we will use a reverse-phase column.我们的溶剂系统将为微酸性（丙腈：水70：30加0.1%甲酸），并使用反相色谱柱。 Which of the two compounds will elute first?两种化合物中哪一种会先被洗脱？ Ketoprofen (image: https://webbook.nist.gov/) 酮普洛芬（图片来源：https://webbook.nist.gov/） Uracil (image: https://webbook.nist.gov/) 尿酸（图片：https://webbook.nist.gov/）

所有校准标准不仅含有酮洛芬（分析物），还含有尿嘧啶作为添加剂。 我们的溶剂系统将为微酸性（丙腈：水70：30加0.1%甲酸），并使用反相色谱柱。 两种化合物中哪一种会先被洗脱？ 酮普洛芬（图片：https://webbook.nist.gov/） 尿酸（图片：https://webbook.nist.gov/）

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