When a research peptide is described as “HPLC verified” or “HPLC + MS tested”, two complementary analytical techniques are doing the work. They are often mentioned together, but they measure different things. Knowing the distinction makes every Certificate of Analysis easier to interpret.
What HPLC measures: purity
高效液相色谱在高压下将溶解的样品推过填充柱。不同的分子以不同的速度穿过色谱柱，具体取决于它们与色谱柱材料相互作用的强度，因此主要肽与相关杂质分离。检测器将每个成分记录为峰值。通过将主峰下的面积相对于总面积进行积分，分析人员可以计算出纯度百分比。
HPLC is therefore a purity tool. It tells you how much of the sample is the dominant compound versus everything else — but on its own it does not prove what that dominant compound actually is.
质谱测量的内容：同一性
Mass Spectrometry (MS) ionises the molecules and measures their mass-to-charge ratio with high precision. For a peptide, the measured mass is compared against the theoretical mass derived from its amino-acid sequence. A close match confirms identity: the molecule really is the sequence on the label, and not a different peptide of similar size.
MS is an identity tool. It is exceptionally good at confirming “this is the right molecule” but is not the primary way purity is quantified.
Why both are used together
Consider the gaps each technique leaves:
- 单独使用 HPLC 就可以显示出纯正的单峰——错误的肽。
- 仅 MS 就可以确认正确的质量——而样品的纯度仅为 80%。
Used together, HPLC answers “how pure?” and MS answers “is it the right molecule?”. A COA that includes both gives a far more complete picture than either in isolation, which is why “HPLC + MS” has become the practical standard for research-grade peptide documentation.
Reading the two results side by side
在合并报告中，您应该看到 HPLC 色谱图（理想情况下是具有规定纯度百分比的干净主峰）和 MS 谱图或表格，其中给出了计算质量旁边的观察质量。检查观察到的质量是否与产品规格上的分子量相符，并且纯度数字是否符合您订购的等级。
Practical takeaways
- 将纯度 (HPLC) 和身份 (MS) 作为两个单独的问题。
- 更喜欢用这两种技术记录的批次。
- 将 MS 观察到的质量与公布的分子量进行匹配。
- 如果可能，请根据独立实验室报告交叉核对这些数字。
一旦您在脑海中清楚地区分这两种技术，研究肽 COA 就不再是一堵数字墙，而是成为一种快速、自信的验证。
引用的化合物是研究级参考材料，仅供实验室使用，不可供人类或动物食用。