Self-assembly and drug release mechanisms of mechano-responsive and antibacterial F127-Rif hydrogels

The self-assembly and drug release mechanism of F127-RIF drug-loaded hydrogels were studied based on dissipative particle dynamics (DPD) simulation. The F127 (PEO 99 -PPO 65 -PEO 99 ) was chosen as the candidate matrix, rifampicin (Rif) was used as an antibacterial drug. The self-assembly procedure and drug release mechanism of the F127 polymeric rifampicin-loaded (F127-Rif) micelles in the aqueous solution were simulated. The results show that F127 macromolecules tended to aggregate into clusters due to their hydrophobic property in an aqueous environment, thus forming a core–shell structure. In the case of low drug loading, the self-assembly process was likely to form multiple relatively dispersed small micelles. When the drug loading reached 15–20%, the drug was exposed because of exceeding the coating limit of the polymer gels. It was more appropriate to control the optimal drug loading at about 10–13%. Under the unidirectional tensile force, the F127-Rif hydrogel bundle was slowly stretched, which helped rifampicin molecules diffuse from the micelle’s core to the outer layer. The greater the force loaded, the higher the drug release efficiency. At the same time, the F127-Rif micelle was cracked and caused the carrier to fail if the tensile force was too large. The appropriate loading force value was 50–70 kcal/mol/Å. Graphical abstract This paper investigated the self-assembly process and mechanism of F127-Rif hydrogels formed by PEO-PPO-PEO and rifampicin in aqueous environment using DPD simulation experiments. With the increase of drug concentration, the micelles gradually aggregate to the center, so that they reach the micelle wrapping limit and diffuse directly into water. The greater the external force loading, the faster the MSD change and the higher the release efficiency