Mass-based Flow Cytometry

描述（由申请人提供）：虽然商业流式细胞仪能够以令人印象深刻的灵敏度进行高通量颗粒分析，但它们对分析小颗粒的灵敏度有限。通过光散射对病毒的检测极限远低于现有的灵敏度，并且已经证明难以检测某些类型的细菌。此外，与其他基于微流体的样品提取和制备芯片的集成仍然很困难。该项目的目标是开发一种全新的流式细胞术方法，该方法基于测量流经悬浮微通道谐振器（SMR）的生物组分的质量。在传统的流式细胞术中，荧光标记的亲和分子（例如抗体）使特定组分（例如细胞）比背景组分更亮，并且荧光标记组分的数量用光学读数来确定。在所提出的方法中，纳米颗粒亲和缀合物将使特定组分比背景组分重，并且纳米颗粒标记的组分的数量将通过用SMR对其进行称重来确定。我们最近已经证明，SMR可以测量溶液中的质量与~1毫微微克的分辨率在一个流通的格式。这样的分辨率代表了比高端商业石英晶体微量天平六个数量级的改进。或者，一毫微微克相当于45纳米金纳米颗粒的质量，或E质量的百分之一。大肠杆菌。本提案的总体目标是开发特定病毒和细胞的聚集试验，并验证SMR定量聚集程度和目标浓度的性能。我们设想SMR的纳米级分辨率加上其鲁棒性，低成本和微流体格式将使基于质量的流式细胞术成为研究环境的有用工具。

DESCRIPTION (provided by applicant): While commercial flow cytometers enable high-throughput particle analysis with impressive sensitivity, they have limited sensitivity for analyzing small particles. The detection limit for viruses by light scattering is well below the existing sensitivity, and the detection of certain types of bacteria has proven to be difficult. Furthermore, integration with other microfluidic-based sample extraction and preparation chips remains difficult. The goal of this project is to develop a fundamentally new approach for flow cytometry that is based on measuring the mass of biological components as they flow through a suspended microchannel resonator (SMR). In conventional flow cytometry, fluorescently labeled affinity molecules (e.g. antibodies) make specific components (e.g. cells) brighter than the background ones, and the number of fluorescently labeled components is determined with optical readout. In the proposed approach, nanoparticle-affinity conjugates will make specific components heavier than the background ones, and the number of nanoparticle labeled components will be determined by weighing them with the SMR. We have recently demonstrated that the SMR can measure mass in solution with ~1 femtogram resolution in a flow-through format. Such a resolution represents a six order of magnitude improvement over a high-end commercial quartz crystal microbalance. Alternatively, one femtogram is equivalent to the mass of a 45 nm gold nanoparticle, or one percent of the mass of an E. coli bacterium in solution. The overall goal of this proposal is to develop aggregation assays for specific viruses and cells, and to validate the performance of the SMR for quantifying the degree of aggregation and hence target concentration. We envision that the nanoscale resolution of the SMR coupled with its robustness, low-cost, and microfluidic format will make mass-based flow cytometry a useful tool for the research environment.