我想用核酸染料来追踪我的细胞，比如DAPI或者Hoechst染料。您有什么建议吗？
这是不推荐的。这些染料与DNA和RNA的结合会影响核酸的正常功能，扰乱转录和增殖。诸如CellTracker染料或Qtracker试剂在不严重扰乱细胞正常活动的条件下对其进行追踪。如果您仍需要使用核酸染料进行标记且细胞是哺乳动物和非血液来源的话，CellLight 细胞核试剂可通过瞬时转染进入细胞，在核表达蛋白上表达GFP或RFP长达数天而不影响其功能。
我想追踪细胞，但贵司有很多产品可供选择，我该如何选择？
请浏览这里（https://www.thermofisher.com/us/en/home/life-science/cell-analysis/cell-tracing-tracking-and-morphology/cell-tracking.html）以帮助您选择适合您的应用的产品。首先确定追踪细胞的时间，然后考虑染料结合机制。钙黄绿素染料标记均匀且对短期细胞迁移示踪效果极佳，但也会被某些类型细胞迅速外排。亲脂性的花青素染料，如DiI，DIO，和类似的染料能标记细胞膜而不破坏其功能，并且能持续更长时间，但如果发生膜融合则可能会染上其他细胞。此外，它们还会在透化过程中丢失。CellTracker染料更有利于长期标记，其带有温和的氯甲基反应基团使之能够与细胞组分共价结合。CFDA SE也能共价地结合于细胞组分。在所有列出的试剂中，细胞内保留与否取决于细胞分裂的速率和细胞的固有特性（主动外排，膜和蛋白质的周转率等）。其中共价结合试剂比非共价结合的试剂展现出更长的保留时间。
Qtracker试剂是最持久并且荧光强度最高的细胞示踪染料，它通过内吞作用被细胞摄入。在许多样品中它们产生的信号可以持续检测长达数周，而且信号足够强，即使在固定和通透甚至加热和石蜡处理过程中，仍然能够维持较好的荧光信号。
我想标记细胞膜，但可选的染料有多种，该如何选择？
如果进行活细胞成像，CellVue和CellMask 质膜染色剂染色最均匀，被细胞内吞的速度最慢。如果想固定和通透细胞（如进行抗体标记），这种产品并不是最佳选择。麦胚凝集素（WGA）偶联物也能标记活细胞，或者甲醛固定的细胞。它们可以在随后的去垢剂（如TritonX-100）通透处理后保存下来。但如果细胞已经进行通透处理，WGA也会标记内部结构。因此，如果细胞已通透，则只能使用靶向质膜蛋白的抗体。亲脂性花青染料（如DiI）会标记活细胞的所有膜结构，而不仅仅是细胞质膜。此网页（https://www.thermofisher.com/us/en/home/life-science/cell-analysis/cell-structure/plasma-membrane.html）的内容可帮助您进行选择。
I'm labeling live cells with Vybrant DiI or DiD lipophilic cyanine dyes. DiI gives a nice even membrane labeling, but DiD is more "spotty". What can be done?
This is expected. DiD (which is far-red fluorescent) is never as uniform as DiI (which is orange fluorescent). If uniformity is desired, try increasing the label time and concentration, but it still isn't likely to be as uniform as DiI. CellMask Deep Red Plasma Membrane stain is much more uniform and is about the same wavelength as DiD. However, if you intend to do cell tracking over days, CellMask stain has not been tried for that application.
Find additional tips, troubleshooting help, and resources within our Cell Analysis Support Center.
I want to track my cells with a nucleic acid stain, like DAPI or Hoechst dye. Do you recommend this?
This is not recommended. When these stains bind to DNA and RNA, they may affect the normal function of the nucleic acids, disrupting transcription, as well as replication. Other reagents, such as CellTracker dyes or Qtracker reagents are more optimized for tracking without disrupting normal activity. If a nuclear label is still desired, though, and the cells are mammalian and non-hematopoietic, CellLight nuclear reagents can transiently transfect cells to express GFP or RFP on a nuclear-expressing protein for up to several days without affecting function.
Find additional tips, troubleshooting help, and resources within our Cell Tracing and Tracking Support Center.
