Production of PMMA Nanoparticles Loaded with Praziquantel Through “In Situ” Miniemulsion Polymerization

Abstract

PZQ is the primary drug for treatment of schistosomiasis, but its efficiency is severely affected by its bitter taste. The main objective of this paper is the preparation of PMMA nanoparticles loaded with PZQ through in situ miniemulsion polymerizations and intended for oral formulations. Polymerizations are performed with an ultra turrax and a high‐pressure homogenizer. Obtained nanoparticles are analyzed by DSC, HPLC, DLS, GC, SEM, and PZQ dissolution profiles. Obtained results indicate the successful encapsulation of PZQ in all runs. Obtained data also show that the high‐pressure homogenizer leads to the best performance, allowing for preparation of stable latexes, with narrower particle size distributions and higher encapsulation efficiencies. magnified image

In Situ Incorporation of Praziquantel in Polymer Microparticles through Suspension Polymerization for Treatment of Schistosomiasis

“…Besides, the DSC thermograms ( Figure 16 ) of the copolymers loaded with PZQ did not present the characteristic melting point of the drug, indicating that PZQ did not form a distinct crystalline phase and was dissolved in the copolymer matrix. Similar interpretations have been reported by Fonseca et al., Mainardes et al., and Lorca et al . for polymer materials loaded with drugs.…”

“…As shown in Figure 5 , PMMA microparticles exhibited narrower molar mass distributions in presence of PZQ. Besides, addition of PZQ shifted the molar mass distributions toward lower molar masses, indicating that the drug affects the kinetic behavior of the reaction system, as also reported by Fonseca et al . and Oliveira et al .…”

“…Similar behaviors were obtained for PMMA microparticles prepared in presence of the additives (Figure B,C), showing that the addition of chloroform and EGDMA was not sufficient to modify the release profiles, confirming the nonporous nature of the polymer matrixes and suggesting that the release process is controlled by diffusion of PZQ through the polymer matrix. It must be observed that Fonseca et al . and Moustafa et al .…”

Comparative Analysis of Sunscreen Nanoencapsulation Processes

“…This can certainly be explained by the high lipophilicity of the used sunscreens, which prevents migration to the aqueous phase. These results confirm the high encapsulation efficiencies reported in other studies for polymer nanoparticles prepared through miniemulsion polymerizations, also allowing for much higher loads of active chemicals when compared to liposomal preparations.…”

“…The thermograms of the analyzed sunscreens also indicate the presence of additional peaks at lower temperatures (possibly related to changes in the crystalline form of the solid phase) and higher temperatures (related to degradation of filters). However, the characteristic melting peak of AVO could not be observed in the thermogram of the nanoparticle loaded with AVO, indicatind that the sunscreen did not form a crystalline phase and was completely dissolved in the polymer matrix, indicating the chemical and physical affinity between AVO and PMMA . In the thermogram of nanoparticles loaded with BZ, a small peak could be observed at 90 °C, suggesting that this chemical was not completely dissolved in the polymer matrix.…”