Dissolution rate enhancement of the poorly water-soluble drug Tibolone using PVP, SiO₂, and their nanocomposites as appropriate drug carriers

Abstract

Immediate release formulation was created for Tibolone as well as new nanocomposite matrices of PVP/SiO((2)), which drastically change the release profile of the drug to a sustained delivery.

Synthesis of biocompatible poly(ε-caprolactone)-block-poly(propylene adipate) copolymers appropriate for drug nanoencapsulation in the form of core-shell nanoparticles

“…Zeta potential values higher than 30 mV show good stability during shelf-life. 35 In the present study, DFOloaded polymers presented zeta potential between −28.21 and −34.60 mV. This range suggests that both suspensions might classify as physically stable, since particle aggregation is not likely to occur under these conditions of electrostatic repulsion between the particles.…”

“…Low values of polydispersity index for all polymer carriers suggest a relatively narrow size distribution. 35 The copolymers with higher PPAd content, as well as neat PPAd, tended to yield nanoparticles with higher size, possibly due to the lower degree of crystallinity of these copolymers. The analysis of zeta potential, which is the electric potential at the plane of shear, is a useful marker to predict the physical storage stability of colloidal systems.…”

Novel Biodegradable Polyesters. Synthesis and Application as Drug Carriers for the Preparation of Raloxifene HCl Loaded Nanoparticles

“…This is an indication that the drug is entrapped mainly in a crystalline phase in the polyesters rather that in the amorphous state, but in a different crystalline structure than the initial drug. This is very usual in drugs that are recrystallized from solvents [ 41 , 42 , 43 ]. Since the size of nanoparticles is lower than 300 nm, it is concluded that the drug is entrapped in polymer nanoparticles in the form of nanocrystals.…”

Desenvolvimento e validação de método para o doseamento de tibolona em cápsulas por cromatografia líquida de alta eficiência

“…8,9 Na literatura foram encontrados estudos que empregam métodos para o doseamento de tibolona e metabólitos em fluidos biológicos e ensaios de dissolução. [10][11][12][13] Foram encontradas monografias em compêndios oficiais com métodos para a determinação do teor deste fármaco em matérias-primas e comprimidos.…”

“…8,9 Na literatura foram encontrados estudos que empregam métodos para o doseamento de tibolona e metabólitos em fluidos biológicos e ensaios de dissolução. [10][11][12][13] Foram encontradas monografias em compêndios oficiais com métodos para a determinação do teor deste fármaco em matérias-primas e comprimidos.14 Embora seja possível a transposição destes métodos para a análise de cápsulas, não existe estudo específico sobre a análise desta forma farmacêutica, que pode apresentar matrizes diferentes de outros formas sólidas. Considerando os aspectos mencionados, o presente trabalho teve por objetivo desenvolver e validar método para a determinação de tibolona em cápsulas, utilizando cromatografia líquida de alta eficiência (CLAE) com detecção no UV.…”