Preparation and properties of drug-carrying microspheres of konjac glucomannan/sodium alginate/hydroxyapatite

Bone tissue engineering microspheres have become a prominent focus in bone repair research. This is due to their potential for targeted therapy and controlled drug release. The current research direction of bone tissue engineering microspheres primarily emphasizes composite microspheres. In this context, konjac glucomannan (KGM) has emerged as a promising composite microsphere preparation material for bone tissue engineering due to its exceptional water-absorbing and swelling properties, as well as its high biocompatibility. In order to expand the application of KGM in the field of bone tissue engineering, microspheres were designed and prepared in this paper by using KGM, hydroxyapatite (HA), and sodium alginate (SA). The quaternary amination modification of KGM was carried out to prepare the white flocculated Cationic Konjac Glucomannan (CKGM). CKGM was prepared in an amorphous state, and FT-IR and 1 H NMR results proved the successful synthesis of CKGM. The preparation of KGM/SA/HA and CKGM/SA/HA microspheres with rough surfaces involved emulsification, cross-linking, and coating methods. These microspheres exhibited absorption peaks for SA and CKGM. In addition, the XRD diffraction peaks of the two were found to be essentially identical to those of HA. The experimental results demonstrated that the drug release process of both drug-carrying microspheres was pH-responsive, with a direct correlation between the pH level and the cumulative release rate, with lower pH values corresponding to higher release rates. And the cumulative release rate of CKGM/SA/HA@DOX microspheres was slightly lower than that of KGM/SA/HA@DOX microspheres. Secondly, both microspheres had good biocompatibility, thermal stability and bacteriostatic properties.