Preparation and characterization of 3s-PLA/CS/nHA drug-loaded composites by supercritical carbon dioxide technology

Amidst the relentless innovation in materials science and bone tissue engineering, the quest for next-generation bone graft materials with bespoke functionalities has emerged as a pivotal research domain. This study produced and characterized a novel bone healing material. First, we explained how three-armed polylactic acid (3s-PLA) was created in supercritical carbon dioxide (ScCO₂) and utilized as a matrix material. Following that, we described how the solution blending approach was employed to create three-armed polylactic acid/chitosan/nanohydroxyapatite (3s-PLA/CS/nHA) composites. The composites were then drug-loaded with prednisone acetate as a model drug utilizing the supercritical impregnation technique. Ultimately, the Ritger-Peppas model was substantially followed by the drug release of the drug-loaded composites when the in vitro drug-release kinetics of the drug-loaded materials were investigated. The porous structure of 3s-PLA was demonstrated by differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR) hydrogen spectroscopy. Morphologic studies using scanning electron microscopy (SEM) revealed the homogeneous distribution of drug in the matrix of the mixtures as well as the porous structure of 3s-PLA and 3s-PLA/CS/nHA. The hydrophilicity of 3s-PLA/CS/nHA was examined by the use of water contact angle (WCA), revealing that the material in question has a hydrophilic water contact angle of 45.69°. Furthermore, research was conducted using one-way tests and investigations to characterize in vitro drug-release carrier materials under various drug conditions and temperatures. The carrier material consistently released up to 84.8% of prednisone acetate over the course of 72 h, demonstrating good control over prolonged release, according to the results.

Graphical abstract