a Schematic of RNA-6 PTXs chemical conjugation and 4WJ-X-24 PTXs self-assembly. b Conjugating six PTXs to an RNA, evaluated by denaturing PAGE. c HPLC chromatogram (absorbance 260 nm) with an inserted gel image of RNA-6 alkynes (blue) and RNA-6 PTXs (red). d Turbidity changes of PTX and RNA-6 PTXs in aqueous solution at two-fold serial dilution. e Step-wise self-assembly of 4WJ-X-24 PTXs and 4WJ-X-24 PTXs-EGFRapt, evaluated by native PAGE (M, D, and T indicate RNA monomer, dimer, and trimer conjugated with PTX, respectively). f Size comparison of 4WJ-X, 4WJ-X-24 PTXs, and PTX in aqueous solution by DLS (n = 3 independent samples, mean ± SD). Source data are provided as a Source Data file.