Saha-Shah Anumita, Green Curtis M, Abraham David H, Baker Lane A
Department of Chemistry, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN 47405, USA.
Analyst. 2016 Mar 21;141(6):1958-65. doi: 10.1039/c6an00028b.
We report development of a mobile and easy-to-fabricate theta pipette microfluidic device for segmented flow sampling. The theta pipettes were also used as electrospray emitters for analysis of sub-nanoliter segments, which resulted in delivery of analyte to the vacuum inlet of the mass spectrometer without multiple transfer steps. Theta pipette probes enable sample collection with high spatial resolution due to micron or smaller sized probe inlets and can be used to manipulate aqueous segments in the range of 200 pL to tens of nanoliters. Optimized conditions can enable sampling with high spatial and temporal resolution, suitable for chemical monitoring in biological samples and studies of sample heterogeneity. Intercellular heterogeneity among Allium cepa cells was studied by collecting cytoplasm from multiple cells using a single probe. Extracted cytoplasm was analyzed in a fast and high throughput manner by direct electrospray mass spectrometry of segmented sample from the probe tip.
我们报告了一种用于分段流动采样的可移动且易于制造的θ移液器微流控装置的开发。θ移液器还用作电喷雾发射器，用于分析亚纳升段，从而无需多次转移步骤即可将分析物输送到质谱仪的真空入口。由于探针入口尺寸为微米或更小，θ移液器探针能够以高空间分辨率进行样品采集，并且可用于处理200皮升至数十纳升范围内的水相段。优化的条件能够实现高空间和时间分辨率的采样，适用于生物样品中的化学监测和样品异质性研究。通过使用单个探针从多个细胞中收集细胞质，研究了洋葱细胞间的异质性。通过对来自探针尖端的分段样品进行直接电喷雾质谱分析，以快速且高通量的方式对提取的细胞质进行了分析。
