行业面试的见解

您能否告诉我们Quadram Institute和牛津工具之间的合作如何？狗万正网地址

The Quadram Institute has worked with high-resolution, high-field NMR (Nuclear Magnetic Resonance) for a number of years, but in 2012, we really started to develop an interest in benchtop technology. Working with the UK's Technology Strategy Board, we began to collaborate with Oxford Instruments – a collaboration that is still active today.

为什么Quadram在植物油组合上的工作如此至关重要？

我们与植物油的主要目标是确定Benchtop NMR是否可以提供标记所需的信息类型。有标准化的参考方法，允许这个 - 例如，GC-FID（气相色谱 - 火焰离子化探测器） - 但我们希望在不需要制备样品的同时开发一种更快的耗材成本。

We take neat oils directly from the bottle before placing these in the NMR tubes for analysis. This means that our test, from beginning to end, only takes five minutes per sample.

Benchtop NMR可以向我们展示什么植物油？

We employ benchtop NMR to examine various parts of the molecules of vegetable oils. Analysing NMR signals from the molecules’ bisallylic and olefinic regions provides us with important information about the degree of unsaturation of the oils.

我们还可以使用来自甘油酯区域的信号来帮助我们量化测量，因为这些信号通常在样品之间是恒定的。一旦我们获得了油的脂肪酸曲线，我们就可以开始将其用于广泛的应用。万博电脑网页版登录

您能否告诉我们您的工作，开发筛选方法来确定魔刀的真实性？

为了开发筛选方法，我们需要提供有保证物质的魔刀油。我们从联合国的粮食和农业组织的联系人中获得了这些石油，该组织对于对农业食品认证的成本效益筛查方法具有特别兴趣的组织。整个样本收集由数百种真实的魔刀，以及一系列可能的掺杂剂组成。

We acquired and processed proton NMR spectra from all the oils. Because argan oil is a natural product, we anticipated a fairly high degree of variation between the spectra, but our results were wholly consistent with the values for different fatty acid proportions provided in the literature.

在排除在储存期间氧化的少量样品之后，我们统计地考虑了剩余的数据，在本集团周围放置置信区。这是我们预期的地方，发现95％的真实魔芋油。

The confidence region provides us with a simple means of detecting mixtures with other oils, down to concentrations of about 20 %. This is a helpful percentage for a rapid screening tool.

Should the fatty acid profile of a contaminating oil be too similar to that of argan oil, however, then this approach would not offer adequate sensitivity.

我们将需要从整个频谱中使用信息，而不仅仅是来自几个峰值积分。为了解决这个问题，我们使用单级建模，也称为异常或异常检测。再次，我们将边界定义为接受或拒绝来自类的项目，但在这种情况下，使用全频谱，并且在数学上，边界更复杂。

你和咖啡也开展工作。为什么咖啡nother important product in the food industry that must be authenticated?

咖啡供应链很长。咖啡只在热带国家生长，但它是在全球范围内加工和消费的。因此，高度重视的阿拉比卡咖啡易受欺诈的影响，因为一旦豆子烤并研磨，就实际上不可能通过目视检查来检测差异。一种形式的分析测试是必要的，因此我们想知道Benchtop NMR是否可以解决这个问题。

从地面烘焙咖啡取悦的亲脂相的质子NMR谱包括来自初级代谢物，分解产物和来自焙烧过程的次要化合物的一系列信号。在60 MHz时，大量这些峰值重叠，因此只能挑选出更多的主要化合物。

Conversely, caffeine gives us some clear, easy to recognize signals. And critically, a small isolated peak can also be seen from a compound called 16-O-methylcafestol, or 16-OMC, which is noteworthy because it seems to be present in extracts from Robusta yet not Arabica coffees.

这可能会提供快速，简单，经济高效的真实性测试的途径。

你能告诉我们关于使用Benchtop NMR识别精神活性药物吗？

This work began a couple of years ago. We had been asked to develop a benchtop NMR test capable of rapidly identifying novel psychoactive drugs, also known as designer drugs or legal highs.

Since then we have expanded this work to examine small-molecule pharmaceuticals, alongside investigating controlled substances more widely. This work has been undertaken in collaboration with Manchester Metropolitan University, an organization which holds one of a handful of UK licenses for the synthesis and storage of these substances.

我在这个特定项目中的工作已经专注于自动化数据分析。与该区域的挑战，特别是用缉获的药物样品，包括来自不受控制的储存，未知的活性成分的未知浓度的样品的因素，以及与其他物质混合的样品。值得庆幸的是，我们现在具有工作常规，能够识别完全未知的样品，例如单个化合物，甚至与赋形剂或其他活性物质的混合物。该例程实现了非常高的准确性。

The approach uses pattern matching against a database of reference compounds, working based on the identification of several nearest neighbours with some extra manipulations that help it work with mixtures. A patent application for this method is currently in progress.

我们从一个未知样品的频谱开始，预处理它仅提取我们想要查看的感兴趣区域。因此，例如，我们可以从溶剂中排除峰值。

The next step in the process is a comparison of the sample spectrum using a database of known compounds. This database includes controlled substances, pharmaceuticals, and a series of excipients - several hundred reference spectra overall. The closest matches are then ranked in order of similarity.

如果找不到近距离匹配，这可能表示混合。在这些情况下，顶部单个化合物匹配的组合将用于通过光谱加成合成进一步的混合光谱集合。最后，将与这些混合物进行比较样品谱，识别最佳总体匹配。

This method and work were recently published in an open-access paper. We looked at more than 400 seized samples in total, throughout the study. Our work allowed us to conclude that benchtop NMR, working alongside pattern recognition technology, offers a highly effective tool for the rapid screening of seized street drugs. In fact, throughout the study, we were able to successfully identify controlled substances in 99 % of the samples that we analysed.

关于Kate Kemsley.

Professor Kate Kemsley is based at Quadram Institute in Norwich, UK, where she is head of the Core Science Resources team. Her group works with a large platform of technologies supporting the science of the institute, such as microscopy, mass spectrometry, flow cytometry, and NMR.