Otro
Loading of praziquantel in the crystal lattice of solid lipid nanoparticles Studies by DSC and SAXS
Registro en:
Journal of Thermal Analysis and Calorimetry. Dordrecht: Springer, v. 108, n. 1, p. 353-360, 2012.
1388-6150
10.1007/s10973-011-1871-4
WOS:000302704500048
0000-0002-7984-5908
Autor
Ribeiro de Souza, Ana Luiza
Andreani, Tatiana
Nunes, Fernando M.
Cassimiro, Douglas Lopes
de Almeida, Adelia Emilia
Ribeiro, Clovis Augusto
Vitorino Sarmento, Victor Hugo
Daflon Gremiao, Maria Palmira
Silva, Amelia M.
Souto, Eliana B.
Resumen
Praziquantel (PZQ) is the drug of choice for oral treatment of schistosomiasis and other fluke infections that affect humans. Its low oral bioavailability demands the development of innovative strategies to overcome the first pass metabolism. In this article, solid lipid nanoparticles loaded with PZQ (PZQ-SLN) were prepared by a modified oil-in-water microemulsion method selecting stearic acid as lipid phase after solubility screening studies. The mean particle size (Z-Ave) and zeta potential (ZP) were 500 nm and -34.0 mV, respectively. Morphology and shape of PZQ-SLN were analysed by scanning electron microscopy revealing the presence of spherical particles with smooth surface. Differential scanning calorimetry suggested that SLN comprised a less ordered arrangement of crystals and the drug was molecularly dispersed in the lipid matrix. No supercooled melts were detected. The entrapment efficiency (EE) and loading capacity of PZQ, determined by high performance liquid chromatography, were 99.06 +/- 0.3 and 17.48 +/- 0.05, respectively. Effective incorporation of PZQ into the particles was confirmed by small angle X-ray scattering revealing the presence of a lipid lamellar structure. Stability parameters of PZQ-SLN stored at room temperature (25 degrees C) and at 4 degrees C were checked by analysing Z-Ave, ZP and the EE for a period of 60 days. Results showed a relatively long-term physical stability after storage at 4 degrees C, without drug expulsion. Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)