Formulation and in vitro characterization of poly(DL-lactide-co-glycolide)/Eudragit RLPO or RS30D nanoparticles as an oral carrier of levofloxacin hemihydrate

The main objective of this study was to design positively charged Levofloxacin Hemihydrate (Levo-h)-loaded nanoparticles with improved entrapment efficiency and antibacterial activity. PLGA alone or in combinations with Eudragit(R) RLPO or RS30D with or without positively charged inducing agent; 1,2-dioleoyl-3-trimethylammonium-propane, chloride salt (DOTAP); were used for preparation of nanoparticles. Blending between PLGA and Eudragit(R) RLPO or RS30D with inclusion of DOTAP caused a marked increase in entrapment efficiency and switched zeta potential from negative to positive. Nanoparticle formulations; NR3 (Levoh: PLGA: Eudragit(R) RLPO; 1: 1: 1 w/w with DOTAP) and NS3 (Levo-h: PLGA: Eudragit(R) RS30D; 1: 1: 1 w/w with DOTAP) that possess high positive zeta potential (59.3 +/- 7.5 and 55.1 +/- 8.2 mV, respectively) and Efficient Levo-h entrapment (89.54 +/- 1.5 and 77.65 +/- 1.8%, respectively) were selected for further examinations; in vitro release, physical stability and microbiological study. NR3 and NS3 showed significant sustained release of Levo-h. NR3 and NS3 exhibited good stability after storage at room temperature. Microbiological assay showed strengthened antibacterial activity of NR3 against both types of gram-negative bacteria (E. coli, Ps. aeruginosa) and of NS3 against Ps. aeruginosa compared to free Levo-h solution. NR3 and NS3 appear to be promising oral delivery system for Levo-h.