IBA-DAPNe: a new system for sub-micron scale molecular speciation and quantification

我们的愿景是开发一种独特的分子成像和剖析资源，使其真正在国际上处于领先地位。分子成像被广泛用于材料的表征，有许多方法可以从表面产生和释放离子，从而生成化学浓度图，包括使用质谱仪(MS)的方法。自2004年以来，在环境条件下分析样品的新的MS方法如雨后春笋般涌现。这使得能够对不兼容真空的样品进行高通量分析，并显著加快了样品处理的速度，这通常是基于真空的技术的时间限制因素。定量、化学形态和空间分辨率是众多应用的三个关键驱动因素，目前还没有一种技术能够在亚微米尺度上提供所有这些属性。直接分析探针纳米提取质谱仪(DAPNe-MS)是一种使用连接到纳米操纵器上的毛细管尖端从表面选择和去除少量物质的方法。然后通过纳米电喷雾电离将提取的物质引入质谱仪。这项技术已经达到了图像级的灵敏度，特别适合于从表面拾取痕量材料。与成像质谱学技术不同，样品移除和电离过程是分离的，碎裂最小。与其他环境下MS方法相比，这提供了更好的选择性和更好的定量机会。由于最近成立，DAPNe在英国还不存在。萨里郡的离子束中心(IBC)拥有世界上唯一提供亚微米分子成像的环境压力成像MeV-二次离子质谱仪(SIMS)系统(EP/I036516/1)。SIMS是一种离子束分析(IBA)技术，以其优异的空间分辨率而闻名，但缺点是在溅射过程中发生碎裂。目前在萨里和NPL可用的技术具有高空间分辨率的成像能力，可以区分分子物种，甚至可以提供分子浓度图。在环境条件下提供ppb级别的痕量元素信息的技术(粒子诱导X射线发射-PIXE，也是一种IBA技术)也很容易获得。缺少的部分是跟踪分子信息，DAPNe将提供这些信息。我们将使用目前的技术来突出特定的区域，这些区域需要使用这种新的独特探头进行更详细的分析，并具有非常高的灵敏度。IBA和DAPNe(IBA-DAPNe)的互补使用在国际上是独一无二的，将在全环境条件下提供前所未有的亚微米级样品表征水平。拟议的IBA-DAPNe系统将为任何学科的研究人员提供缺失的信息，研究项目将根据科学卓越程度进行优先排序。头两年将免费提供访问。我们看到那些在EPSRC的6个关键主题工作的人特别受益：能源、面向未来的制造、医疗保健技术、全球不确定性、ICT和工程。

Our vision is to develop a unique resource for molecular imaging and profiling that will be truly internationally leading. Molecular imaging is widely used for the characterisation of materials, and there are numerous methods available for generating and liberating ions from a surface and hence generating a chemical concentration map including those using mass spectrometry (MS). Since 2004, there has been an explosion of new MS methods in which a sample is analysed under ambient conditions. This has enabled the high throughput analysis of samples that are not vacuum compatible and has significantly speeded up the sample handling, which is often the time-limiting factor of vacuum-based techniques. Quantification, chemical speciation and spatial resolution are three key drivers for a multitude of applications, and there is currently not a single technique that can provide all these attributes at the sub-micron scale.Direct Analyte Probed Nano Extraction Mass Spectrometry (DAPNe-MS) is a method of selecting and removing a small quantity of material from a surface, using a capillary tip attached to a nanomanipulator. The extracted material is then introduced into a mass spectrometer via nanoelectrospray ionisation. The technique has achieved sensitivity at the attogram level and is particularly suited to picking up trace materials from surfaces. Unlike imaging mass spectrometry techniques, the process of sample removal and ionisation are decoupled and there is minimal fragmentation. This provides better selectivity and opportunities for superior quantification compared with other ambient MS methods. Due to its recent inception, no DAPNe facility exists in the UK. Surrey houses in its Ion Beam Centre (IBC) the only ambient pressure imaging MeV-Secondary Ion Mass Spectrometry (SIMS) system in the world which offers sub-micron molecular imaging (EP/I036516/1). SIMS, an Ion Beam Analysis (IBA) technique, is known for its excellent spatial resolution but a drawback is the fragmentation that occurs during the sputtering process. Currently available techniques at Surrey and NPL have imaging capability with high spatial resolution, can distinguish between molecular species and even provide molecular concentration maps. Techniques which provide trace element information at the ppb level in ambient conditions (Particle Induced X-ray Emission - PIXE, also an IBA technique) are also readily available. The missing component is trace molecular information, which DAPNe will provide. We will use current techniques to highlight specific regions which require a more detailed analysis with very high sensitivity using this new unique probe. Complementary use of IBA and DAPNe (IBA-DAPNe) is unique internationally and would provide unprecedented level of characterisation of samples at the sub-micron scale in full ambient conditions. The proposed IBA-DAPNe system will provide missing information for researchers from any discipline and research projects will be prioritised on the basis of scientific excellence. Access will be provided free of charge for the first two years. We see particular benefits for those working across 6 key EPSRC themes: Energy, Manufacturing for the Future, Healthcare Technologies, Global Uncertainties, ICT and Engineering.