Effect of 70-kDa and 148-kDa dextran hydrogels on praziquantel solubility

Abstract

Praziquantel is an anthelmintic widely used in the treatment of schistosomiasis. Although a highly permeable drug, praziquantel is poorly soluble in water, limiting its bioavailability. Improving the solubility of poorly watersoluble drugs has become an important issue for analysis in pharmaceutical research. The use of dextran hydrogels is an advantageous strategy and the focus of extensive research. In this study, several hydrogels were developed from homologous polymer blends using 70 and 148 kDa dextrans in different proportions containing praziquantel, with the aim of evaluating the effects of polymeric release systems on the solubility of poorly water-soluble drugs such as praziquantel. Nine formulations were prepared, and the solubility of the drug incorporated was assessed. Three of the formations were selected to be characterized by DSC for the study in order to gain a better understanding of the thermal behavior of praziquantel incorporated into dextran hydrogels and the influence of polymers on the solubility of the drug, complemented by XRD and SEM techniques. According to the results, formation of crystallites of praziquantel occurred, probably due to the preparation procedures of the formulations, covering the surface of the polymer matrix and promoting a slight improvement in solubility.These data show that the use of hydrogels for the purposes of improving the solubility of poorly water-soluble drugs represents an effective strategy.

Dextran: Sources, Structures, and Properties

“…There is no direct relationship between the characteristics of the molecule and the variation of the properties [14,35,41,68,79]. However, regardless of the degree of solubility, dextrans are considered soluble EPS due to their ability to incorporate large amounts of water and form hydrogels [80].…”

“…The rheology and viscosity of polymers show their behavior as flow or deformation under an applied force, respectively [81], which is associated with -OH groups that easily interact with other molecules through hydrogen bonds, which are they break during shear [80]. Generally, the viscosity of dextran is directly related to the concentration and the shear rate, which means that at low concentrations they have a Newtonian behavior (independent of the shear rate) and at high concentrations their behavior is non-Newtonian (or pseudoplastic) [29].…”

Short Communication: Dextran production using Leuconostoc mesenteroides strains isolated from Borassus flabellifer sap

“…The solubility and rheological properties of dextran are influenced by its molecular weight and branching (Guo et al 2017). Dextran is a soluble type of EPS because of its ability to combine large amounts of water and form hydrogels (Campos et al 2016).…”