Novel amphiphilic heparin-pluronic P123 copolymers exhibiting a great potential for Cisplatin delivery

In the study, we introduced a series of amphiphilic pluronic P123-conjugated heparin (hep-P123) copolymers which were characterized for drug delivery. In regard to the research, various grafted hep-P123 copolymers investigated its potential in the delivery of hydrophobic Cisplatin (Cis) anticancer drugs and its aquated species (CisOH) via hydrophobic interaction and complex formation, respectively. Hep-P123 was obtained via conjugation of the partially NPC-activated pluronic P123 (NPC-P123-OH) onto the aminated heparin (hep-DAB). The obtained copolymers were characterized by ¹H-NMR and thermal gravimetric analysis. The effect of P123 conjugation degree on size distribution of nanocarriers was evaluated by transmission electron microscopy (TEM) and dynamic light scattering (DLS). The results showed that size distribution of hep-P123 nanogels range from 62.2 ± 19.4 nm to 114.5 ± 21.7 nm by TEM and 94.4–182.4 nm by DLS. Complex formation of the CisOH was clarified by FT-IR. Loading efficiency of Cis/CisOH was evaluated by inductively coupled plasma atomic emission spectroscopy that indicated a relation between the conjugated degree of hep-P123 and amount of loaded drugs. In addition, hep-P123 exhibited a higher CisOH binding efficiency via complexation as compared to the loaded Cis by hydrophobic interaction. The CisOH and hep-P123 nanocomplex performed a high activity against NCI-H460 cancer cell growth. The obtained results offered an appropriate selection of the hep-P123 platform for dual drugs delivery of CisOH and other hydrophobic anticancer drugs which could utilize both hydrophobic interaction and complex formation.