Vancomycin-loaded N,N-dodecyl,methyl-polyethylenimine nanoparticles coated with hyaluronic acid to treat bacterial endophthalmitis: Development, characterization, and ocular biocompatibility.

Vancomycin-loaded N,N-dodecyl,methyl-polyethylenimine nanoparticles coated with hyaluronic acid (VCM-DMPEI nanoparticles/HA) were synthesized as an adjuvant for the treatment of bacterial endophthalmitis. The nanoparticles were formulated by experimental statistical design, thoroughly characterized, and evaluated in terms of bactericidal activity and both in vitro and in vivo ocular biocompatibility. The VCM-DMPEI nanoparticles/HA were 154 ± 3 nm in diameter with a 0.197 ± 0.020 polydispersity index; had a + 26.4 ± 3.3 mV zeta potential; exhibited a 93% VCM encapsulation efficiency; and released 58% of the encapsulated VCM over 96 h. VCM and DMPEI exhibited a synergistic bactericidal effect. The VCM-DMPEI nanoparticles/HA were neither toxic to ARPE-19 cells nor irritating to the chorioallantoic membrane. Moreover, the VCM-DMPEI nanoparticles/HA did not induce modifications in retinal functions, as determined by electroretinography, and in the morphology of the ocular tissues. In conclusion, the VCM-DMPEI nanoparticles/HA may be a useful therapeutic adjuvant to treat bacterial endophthalmitis.

Nanoemulsion composed of 10-(4,5-dihydrothiazol-2-yl)thio)decan-1-ol), a synthetic analog of 3-alkylpiridine marine alkaloid: development, characterization, and antimalarial activity.

Malaria treatment is based on a reduced number of antimalarial drugs, and drug resistance has emerged, leading to the search for new antimalarial drugs incorporated into pharmaceutical formulations. In this study, 10-(4,5-dihydrothiazol-2-yl)thio)decan-1-ol) (thiazoline), a synthetic analog of 3-alkylpiridine marine alkaloid, and a potent antimalarial substance, was incorporated into O/W nanoemulsion. This formulation was prepared by a 23 factorial design. It was characterized by globule diameter, polydispersity index, zeta potential, encapsulation efficiency, in vitro thiazoline release at pH 2 and 6.86, and accelerated stability. In vitro and in vivo antimalarial activity was determined against P. falciparum and P. berghei, respectively. Thiazoline nanoemulsion showed 248.8 nm of globule diameter, 0.236 of polydispersity index, -38.5 mV of zeta potential, 96.92% encapsulation efficiency, and it was stable for 6 months. Thiazoline release profiles differed in acidic and neutral media, but in both cases, the nanoemulsion controlled and prolonged the thiazoline delivery. Thiazoline nanoemulsion exerted in vitro antimalarial activity against the parasite (IC50 = 1.32 µM), and it significantly reduced the in vivo parasitemia for 8 days without increasing the survival time of animals. Therefore, the thiazoline nanoemulsion represents a strategy to treat malaria combining an antimalarial candidate and a new nanocarrier.