Since we have used a fairly short ester linker between Ptx (bulky and very hydrophobic) and the polymer backbone (also hydrophobic), even lower IC 50 values could be reached by using a more hydrophilic, solvated linker thanks to the versatility of this synthetic approach. Importantly, nanoparticles PT2* showed greater cytotoxicity than nanoparticles PT1, demonstrating that making degradable polymer prodrug nanoparticles by rROPISA did not impair cytotoxicity, which is a significant improvement compared to the previous work in the field. Interestingly, nanoparticles PT1, PT4 and PT6 exhibited fairly similar IC 50 values, suggesting that F CKA or F ptx do not contribute significantly to nanoparticle cytotoxicity, and that there is no significant impact of using BMDO rather than MPDL.