In contrast to the other two polymers, A-pBuOx-A micelles seem to shrink in size in the presence of CUR. At a CUR concentration of 1 g/L, the overall size of the micelles reduces to approximately 60 Å, even though a second shell becomes apparent (Figure and). This can be explained by splitting of the initial shell into shell 1 and shell 2. Therefore, the thickness of the first shell is reduced by half and also the core size is reduced (Figure and). Such a compaction of the aggregate structure could be a hint towards strong polymer-CUR interactions. Interestingly, stronger drug-polymer interactions were recently suggested in the system A-pBuOx-A/CUR compared to A-pPrOzi-A/CUR by fluorescence up-conversion studies. Although A-pPrOzi-A enables extremely high CURloadings up to 54 wt.%, in contrast to 24 wt.% of A-pBuOx-A , at low loading, the molecular mobility of CUR within A-pBuOx-A was lower than in A-pPrOzi-A. This was interpreted with stronger, more defined A-pBuOx-A/CUR interactions, whereas CUR seemed to be more loosely incorporated into A-pPrOzi-A.