eGFP(cy5) mRNA is a chemically modified synthetic mRNA designed for high-sensitivity tracking of gene delivery processes. The compound features a dual-functional design: its nucleotide sequence encodes the enhanced Green Fluorescent Protein (eGFP) to quantify translation efficiency, while the mRNA backbone is covalently labeled with the near-infrared fluorophore Cy5. This dual-labeling system enables researchers to distinguish the physical distribution of mRNA (uptake/endocytosis, visualized as Cy5 red signal) from its functional biological activity (protein expression, visualized as eGFP green signal) at the single-cell level. It is widely utilized in lipid nanoparticle (LNP) formulation optimization, endocytic pathway elucidation, and tissue distribution studies.