Nanoincorporation of Plumbagin in Micelles Increase Its in Vivo Anti-Plasmodial Properties

BACKGROUND: The application of plumbagin (PLN), with a wide use in pharmaceutical science, is limited due to its low water solubility and poor bioavailability. Micelles can encapsulate hydrophobic drugs due to their hydrophobic core. The aim of this study was to develop and characterize a polymeric micelle formulation of PLN and evaluate its in vivo anti-plasmodial property. METHODS: The study was conducted at Zanjan University of Medical Sciences, Zanjan, Iran in 2018. The triblock copolymeric micelles of PLN was prepared by e-caprolactone ring-opening polymerization, by PEG as the macroinitiator and using Sn(Oct)(2) for its catalytic properties. The synthesized nanoparticles were characterized by (1)H NMR, FTIR, GPC, AFM, and DLS. The encapsulation efficiency, drug loading capacity, and drug release were measured by UV-Vis at 520 nm. Also in vivo anti-plasmodial potential of fabricated drug loaded micelle was investigated using the 4-day suppressive test against Plasmodium berghei infection in mice. RESULTS: The nanoparticles average diameter was obtained less than 80 nm. The loading capacity and encapsulation efficiencies were 18.9±1.3% and 81±0.78%, respectively. In vitro, PLN release studies showed a sustained-release pattern until 7 days in PLN-loaded micelles (M-PLN) and drug release rate in acidic condition was higher than neutral condition. In vivo, anti-plasmodial results against P. berghei displayed an 8-fold increase in anti-plasmodial activity of M-PLN when compared to free PLN at the tested dosage level on the 7(th) day. CONCLUSION: Based on these results, PCL–PEG–PCL micelles have a great potential to be the carrier for PLN for the malaria targeting.