PLA membranes loaded with dba analogs. Controlled release study during hydrolitic degradation

Abstract

In this research two dibenzylideneacetone (DBA) analogs compounds: (1E,4E)-1-(4-(dimethylamino)phenyl)-5-(4-methoxyphenyl)penta-1,4-dien-3-one (DBA-1) and (1E,4E)-1-(4-methoxyphenyl)-5-(4-nitrophenyl)penta-1,4-dien-3-one (DBA-2) were encapsulated in poly(lactic acid) (PLA) membranes. These DBA analogs can have several applications such as in the development of controlled drug release systems and tissue engineering. The membranes were elaborated by solvent casting. It was found that these fluorescent compounds have a small percentage of hemolysis in human blood red cells at concentrations between 200-500 µg/mL. Therefore, they can be considered not-toxic at these concentrations. The hydrolytic degradation of PLA membranes loaded with the DBA analogs was studied at a temperature of 37 °C under solutions at acid, neutral, and basic pH conditions for a maximum time of six weeks. The hydrolysis was monitored by measuring the loss of mass of the membranes, changes in pH environments, variations in the molecular weight of PLA matrix, and changes in surface morphology observed through Scanning the Electron Microscopy (SEM) technique. Applying UV-visible spectrophotometry, the amount released from the DBA analogs in the PLA membranes was determined during the degradation time, and finally, the release profile was obtained. It was observed employing SEM that the membranes presented a major degradation under basic pH conditions, with a higher percentage of release in an acid medium for both analogues of DBA studied