Development of a Novel Hydrogel to Prevent Bacterial Infectious Diseases

Abstract

Temperature-induced phase separation (TIPS) technique was applied to create cyclodextrin (CD) immobilized 2-hydroxypropyl cellulose (HPC) gel sheets. A heterogeneous polymer network could be fixed when the reaction temperature was stepwise increased above a lower critical solution temperature (LCST) of the HPC polymer at approximately 40°C during the cross-linking reaction. Dynamics of polymer network formation was characterized by measuring the viscosity change of the pre-gel solution with or without the TIPS process. A temperature increase is responsible for drastic increase of the viscosity of which change was translated as the acceleration of the cross-linking reaction rates. The immobilized α-CD or hydroxypropyl-β-CD (HP-β-CD) onto the TIPS-generated polymer network effectively decreased the production of red pigment prodigiosin that was one of the second metabolites through the cell-population-density dependent quorum sensing (QS) system in Serratia marcescens AS-1. Since virulence expression in some opportunistic pathogens was regulated by diffusible acylhomoserine lactone (AHL) mediated QS system, trapping AHLs onto the host matrices could make the CD-immobilized gels interrupt the hierarchical QS system from outside of cells. The AHL-mediated prodigiosin production could be drastically decreased to approximately 10% using the CD-AHL inclusion complex formation when the TIPS process was applied to HPC/α-CD gel synthesis with optimized condition of the phase separation.