Detection of mRNA expression in live cells during treatment is a challenging task, despite its importance in tumor biology and potential therapeutic leads. Here a multilayer ratiometric fluorescent nanomachine for live‐cell perturbation and imaging of mRNA at single cell resolution is reported. The nanomachines fabricated by microfluidic approaches consist of fluorescent polymeric cores and multiple lipid layers, which can efficiently deliver siRNA and molecular beacons (MBs) to cytosol and then release the cargo in a sequential way. The siRNA molecules released from the outer lipid layers lead to silencing of multidrug resistance 1 (MDR1) gene, and the MBs from the middle lipid layers detect the presence of MDR1 mRNA. The fluorescent ratio of MBs to fluorescent polymeric cores positively correlates with the expression level of MDR1 mRNA in MCF‐7/ADR cells during siRNA treatment. The nanomachines provide comparable results with traditional qPCR for quantifying mRNA, showing great potential for modulation and imaging of intratumoral mRNA in vitro and in vivo.

中文翻译：

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用于在活细胞中成像 mRNA 的多层比例荧光纳米机器

尽管在肿瘤生物学和潜在的治疗线索中很重要，但在治疗期间检测活细胞中的 mRNA 表达是一项具有挑战性的任务。本文报道了一种用于活细胞扰动和单细胞分辨率下 mRNA 成像的多层比例荧光纳米机器。通过微流体方法制造的纳米机器由荧光聚合物核心和多个脂质层组成，可以有效地将 siRNA 和分子信标 (MBs) 传递到细胞质，然后以顺序方式释放货物。从外部脂质层释放的 siRNA 分子导致多药耐药性 1 (MDR1) 基因沉默，而来自中间脂质层的 MBs 检测到 MDR1 mRNA 的存在。在 siRNA 处理期间，MBs 与荧光聚合物核心的荧光比率与 MCF-7/ADR 细胞中 MDR1 mRNA 的表达水平呈正相关。纳米机器提供了与传统 qPCR 定量 mRNA 相当的结果，显示出在体外和体内调节和成像瘤内 mRNA 的巨大潜力。