Single-cell detection and linear discriminant analysis of bacterial Raman spectra in glass filter microholes.

We report a study of micro-Raman spectroscopy towards an optimal approach for single cell measurements for the detection of bacteria by vibrational spectroscopy. The use of glass membrane filters was tested by microfiltration to separate individual bacterial cells. The glass membrane filters were applied to the study of Raman spectral classification analysis. This approach achieved the capture and individual detection of spiked bacterial cells. Linear discriminant analysis (LDA) of Raman spectra measured on glass membrane filters was successfully used to distinguish several bacterial species.

High-performance glass filters for capturing and culturing circulating tumor cells and cancer-associated fibroblasts.

Various liquid biopsy methods have been developed for the non-invasive and early detection of diseases. In particular, the detection of circulating tumor cells (CTCs) and cancer-associated fibroblasts (CAFs) in blood has been receiving a great deal of attention. We have been developing systems and materials to facilitate such liquid biopsies. In this study, we further developed glass filters (with various patterns of holes, pitches, and non-adhesive coating) that can capture CTCs, but not white blood cells. We optimized the glass filters to capture CTCs, and demonstrated that they could be used to detect CTCs from lung cancer patients. We also used the optimized glass filters for detecting CAFs. Additionally, we further developed a system for visualizing the captured cells on the glass filters. Finally, we demonstrated that we could directly culture the captured cells on the glass filters. Based on these results, our high-performance glass filters appear to be useful for capturing and culturing CTCs and CAFs for further examinations.