Noninvasive, safe and cost-effective cell viability assay is important in many fields of biological research such as cell culture and counting. We examined ten typical natural pigments extracted from food to find that Monascus pigment (MP) or anthocyanin pigment (AP: purple sweet potato and purple cabbage) with Tris (Trimethylolaminomethane) works as a good indicator of viability assay for dye exclusion test (DET) of Paramecium. This was confirmed spectrally by scan-free, non-invasive absorbance spectral imaging A (x, y, λ) microscopy. We developed a new method of cell capture using a metal mesh to confine live Paramecium in a restricted space. This has the advantage that a low-cost and robust capture can be fabricated without using special equipment, compared to a conventional lab-on-a-chip. As a result, MP and AP stained dead cells as quick as methylene blue (MB), a synthetic dye conventionally used in DET within 1 min when treated with microwave and benzalkonium chloride. The natural pigments with Tris had little effect on inhibiting the growth of Paramecium, but MB killed all the cells within 1 h. MP is most useful because it allows non-invasive DET without Tris. This approach provides less invasive and safe DET.

无创、安全且经济高效的细胞活力测定在细胞培养和计数等许多生物学研究领域中非常重要。我们检查了从食品中提取的十种典型天然色素，发现红曲色素 (MP) 或花青素色素 (AP：紫甘薯和紫甘蓝) 与 Tris（三羟甲基氨基甲烷）可作为染料排除试验 (DET) 活力测定的良好指示剂草履虫。_ 这通过免扫描、非侵入性吸收光谱成像A ( x , y , λ ) 显微镜进行了光谱证实。我们开发了一种新的细胞捕获方法，使用金属网将活草履虫限制在有限的空间内。与传统的芯片实验室相比，其优点是无需使用特殊设备即可实现低成本且稳健的捕获。结果，当用微波和苯扎氯铵处理时，MP 和 AP 对死细胞的染色速度与亚甲蓝 (MB) 一样快，亚甲蓝是 DET 中常用的合成染料，可在 1 分钟内完成。含有Tris的天然色素对抑制草履虫生长作用不大，但MB在1小时内杀死了所有细胞。MP 是最有用的，因为它允许在没有 Tris 的情况下进行非侵入性 DET。这种方法提供了侵入性较小且安全的 DET。