Synlogic Therapeutics, Cambridge, MA 02215, United States of America.
Department of Advanced Technology R&D, Nexcelom Bioscience LLC., Lawrence, MA 01843, United States of America.
J Microbiol Methods. 2022 Jan;192:106381. doi: 10.1016/j.mimet.2021.106381. Epub 2021 Nov 23.
The improvement of cell enumeration methods for the counting of Escherichia coli (E. coli) is important as E. coli gains in popularity as a basis for biopharmaceutical applications. In the biopharmaceutical industry, enumerating, characterizing, and dosing the accurate number of cells is imperative. In this work, we demonstrate the utilization of a chip-based image cytometer using a thin-gap, low volume counting chamber consumable to directly enumerate E. coli in bright field and fluorescence, and measure their viability using SYTOX™ Green. The total E. coli particles can be counted accurately label-free by adjusting the focus and targeting the linear range of the instrument. The E. coli are stained with SYTOX™ Green to count the membrane-compromised dead bacterial cells in the green fluorescence channel, while the total cells are counted using the bright field channel. Optimization of the system settings, image focus, cell counting range, and staining conditions have yielded a precise, rapid, and accurate E. coli cell enumeration and viability measurement.
提高用于计数大肠杆菌（E. coli）的细胞计数方法非常重要，因为大肠杆菌作为生物制药应用的基础越来越受欢迎。在生物制药行业中，计数、表征和准确剂量细胞数量是至关重要的。在这项工作中，我们展示了使用基于芯片的图像细胞仪的应用，该仪器使用薄间隙、小体积计数室耗材，可以直接在明场和荧光下对大肠杆菌进行计数，并使用 SYTOX™ Green 测量其活力。通过调整焦点并针对仪器的线性范围，可以对总大肠杆菌颗粒进行准确的无标记计数。SYTOX™ Green 对大肠杆菌进行染色，以在绿色荧光通道中计数膜受损的死细菌细胞，而总细胞则使用明场通道进行计数。对系统设置、图像焦点、细胞计数范围和染色条件进行优化，可实现精确、快速和准确的大肠杆菌细胞计数和活力测量。
