DEVELOPMENT OF AN INTELLIGENT SAMPLE INTRODUCTION SYSTEM FOR MASS SPECTROMETRY

描述：用于质谱分析的智能进样系统的开发迫切需要新的技术来实现快速测量，而不会对分析数据造成重大影响。在这里，我们建议开发一种基于强健的质谱仪(MS)的表面采样设备，该设备能够直接分析包括生物组织和活微生物在内的各种材料，有望实现这一目标。该设备的基础是液体微连接表面采样探头(LMJSSP)，这是一组同轴微流控毛细管，被泵送和吸入以将溶剂带到感兴趣的表面和远离感兴趣的表面，其中微量提取在探头和样品之间的界面上进行。Prosolia已经从AB Sciex获得了LMJSSP技术的许可，并将通过NIH Lab to Marketplace计划与橡树岭国家实验室的原始发明者合作，通过使该技术更加强大和用户友好，用于各种生物分析工作流程中的应用，创造出面向商业可行产品的先进原型。这个项目的任务可以分为三个目标。第一个和第二个目标是确保设备的硬件足够易于使用 商业可行性。这包括对当前原型的表征，以及探索一些有希望的方法来自动控制匹配的液体流量，这是连续萃取连接保持在探头和表面之间所需的。此外，建立一种在探头和表面之间保持理想距离的机制将是成功实施的关键。一旦建立了具有优化控制和合理制造潜力的流量和高度管理方法，这些硬件改进将用于确定仪器运行的分析条件。具体而言，将制定标准，以确定在各种条件下(包括在不同的实验室内)提取的情况和效率。这些将确定潜在使用、维护和支持的预期限制，以确保针对各种方法校准的稳健操作。在这一部分的工作中，将对通过较小的变体从标准探测布置到分辨率的潜在提高进行调查，以确定诊断和生物标记物研究人员感兴趣的组织学上相关样本大小的分析指标。使用另一种基于MS的表面采样技术-解吸电喷雾电离对活微生物进行直接生物分析的早期实验能够生成细菌菌落的光谱图谱；然而，生成这些结果的过程需要频繁清洗和交换仪器毛细管，因为细菌从表面吹出进入仪器入口。使用我们的原型LMJSSP系统获得的初步光谱已经以一种更容易的方式收集，并显示了一些特别有趣的特征，用于区分和表征不同的细菌物种和菌株。然而，为了确定这些数据的统计意义和适用性，必须获取更多的指纹。此外，我们将建立在不同生长点和胁迫条件下采样的影响，以便生成一个潜在的自动分类文库。在实施了自动化和优化的更改后，我们用于直接分析表面的原型将是一个简单的样本引入系统，从少数人使用的学术原型过渡到可以部署到许多人的商业原型。通过遵循我们提出的里程碑：进行适当的硬件更改，确定与溶剂和探针大小对应的分析指标，并收集用于细菌分析的统计相关数量的配置文件，将评估不插手微生物图谱的能力。因此，我们的第二阶段提案将包括进一步的硬件改进、更广泛的样本选择、增强的数据集成和处理软件。

DESCRIPTION: Development of an Intelligent Sample Introduction System for Mass Spectrometry There is a pressing need for new technologies that enable rapid measurements without significant compromise to the analytical data. Herein, we propose to develop a robust mass spectrometry (MS) based surface sampling device that enables direct analysis of a variety of materials including biological tissue and live microorganisms that promises to deliver on this objective. The basis for this device is the Liquid Micro junction Surface Sampling Probe (LMJSSP), a set of coaxial microfluidic capillaries that are pumped and aspirated to bring solvent to and away from a surface of interest, where micro extraction takes place at the interface between the probe and the sample. Prosolia has licensed the LMJSSP technology from AB Sciex and will partner with the original inventor at Oak Ridge National Laboratory via the NIH Lab to Marketplace program to create an advanced prototype towards a commercially viable product by making the technology more robust and user-friendly for applications in various bio analytical workflows. The tasks of this project can be divided into three Aims. The first and second Aims are to ensure that the hardware of the device is sufficiently easy to use for commercial viability. This includes characterization of the present prototype and exploration of a few promising methods for automatic control of matched liquid flows required for a continuous extractive junction to persist between probe and surface. Additionally, establishing a mechanism for maintaining an ideal distance between the probe and surface will be critical for successful implementation. Upon establishing methods for flow and height management with optimized control and reasonable potential for manufacture, these hardware modifications will be used to determine the analytical conditions for instrument operation. Specifically, standards will be created to determine the profile and efficiency of extraction under a variety of conditions (including within different laboratories). These will determine the expected limits for potential use, maintenance, and support to ensure robust operations calibrated for a variety of methodologies. During this section of work, investigations into potential increases in resolution from the standard probing arrangement via smaller variants will be performed to identify analytical metrics at histologically relevant sampling sizes of interest to diagnostic and biomarker researchers. Early experiments using another MS-based surface sampling technique, Desorption Electrospray Ionization, for direct bio analysis of live microorganisms were able to generate spectral profiles for bacterial colonies; however, the process to generate these results required frequent cleaning and exchanging of instrument capillaries due to fouling with bacteria that were blown off the surface and into the instrument inlet. Preliminary spectra obtained using our prototype LMJSSP system have been collected in a much more facile manner, and have shown some particularly interesting features for distinguishing and characterizing different species and strains of bacteria. However, more fingerprints must be acquired in order to determine statistical significance and applicability of these data. In addition, we will establish he effects of sampling at various growth points and stress conditions in order to generate a potential library for automated classification. After implementing changes for automation and optimization, our prototype for direct analysis of surfaces, will be a simple sample introduction system transitioning from an academic prototype used by a few to a commercial prototype that can be deployed to many. By hewing to the milestones we propose: making appropriate hardware changes, determining analytical metrics corresponding to solvents and probe sizes, and gathering a statistically relevant number of profiles for bacterial analysis, the capacity for hands-off microorganism profiling will have been assessed. As such our phase II proposal will include further hardware refinements, a broader selection of samples, enhanced data integration, and processing software.