The delivery of therapeutics across the cell membrane and into the cytoplasm is a major challenge that limits the development of new therapies. This challenge is compounded by the lack of a general assay for cytosolic delivery. Here we develop this assay based on the pro-fluorophore CrAsH-EDT2, and provide cytosolic penetration results for a variety of drug delivery agents (polyethyleneimine, poly-arginine, Ferritin, poly [maleic anhydride-alt-isobutene] grafted with dodecylamine, and cationic liposomes) into HeLa and T98G cells. Our results show that this method can be widely applicable to different cells and drug delivery agents, and yield statistically robust results. We later use this method to optimize and improve a model drug delivery agent's (Ferritin) cytosolic penetration.

治疗剂穿过细胞膜进入细胞质是限制新疗法开发的主要挑战。由于缺乏细胞溶质递送的一般测定，这一挑战变得更加复杂。在这里，我们基于前荧光团 CrAsH-EDT2 开发了这种检测方法，并提供了各种药物递送剂（聚乙烯亚胺、聚精氨酸、铁蛋白、接枝了十二胺的聚 [马来酸酐-alt-异丁烯]和阳离子脂质体）进入 HeLa 和 T98G 细胞。我们的结果表明，这种方法可以广泛适用于不同的细胞和药物递送剂，并产生统计稳健的结果。我们后来使用这种方法来优化和改进模型药物输送剂（铁蛋白）的细胞溶质渗透。