One-step formation of lipid-polyacrylic acid-calcium carbonate nanoparticles for co-delivery of doxorubicin and curcumin PengJianqing FumotoShintaro MiyamotoHirotaka ChenYi KurodaNaotaka NishidaKoyo 2017 <p>A doxorubicin (Dox) and curcumin (Cur) combination treatment regimen has been widely studied in pre-clinical research. However, the nanoparticles developed for this combination therapy require a consecutive drug loading process because of the different water-solubility of these drugs. This study provides a strategy for the “one-step” formation of nanoparticles encapsulating both Dox and Cur. We took advantage of polyacrylic acid (PAA) and calcium carbonate (CaCO<sub>3</sub>) to realise a high drug entrapment efficiency (EE) and pH-sensitive drug release using a simplified preparation method. Optimisation of lipid ratios and concentrations of CaCO<sub>3</sub> was conducted. Under optimal conditions, the mean diameter of PEGylated lipid/PAA/CaCO<sub>3</sub> nanoparticles with encapsulated Cur and Dox (LPCCD) was less than 100 nm. An obvious pH-sensitive release of both drugs was observed, with different Dox and Cur release rates. Successful co-delivery of Cur and Dox was achieved via LPCCD on HepG2 cells. LPCCD altered the bio-distribution of Dox and Cur <i>in vivo</i> and decreased Dox-induced cardiotoxicity. The current investigation has developed an efficient ternary system for co-delivery of Dox and Cur to tumours, using a “one-step” formation resulting in nanoparticles possessing remarkable pH-sensitive drug release behaviour, which may be valuable for further clinical studies and eventual clinical application.</p>