〔Abstract〕 Objective To investigate the antibacterial properties and biocompatibility of a novel hydrogel fabricated by integrating plasma-activated water(PAW) and bletilla striata polysaccharide(BSP).Methods The experiments were carried out by dividing the hydrogels into four groups based on their compositions:the deionized water(DW)-carbomer 940(CBM940)-carboxymethyl chitosan(CMCS) hydrogel group(H group),the PAW-CBM940-CMCS hydrogel(PAH) group,the DW-BSP-CBM940-CMCS hydrogel(BSPH) group,and the PAW-BSP-CBM940-CMCS hydrogel(PA/BSPH) group.Physical properties of the hydrogels were evaluated by testing water loss rate and water vapor transmission rate.The content of active substances was determined using a microplate reader and an electron spin resonance spectrometer(ESR).The pH and ORP values were measured using a pH meter and an oxidation-reduction potential(ORP) electrode.The antibacterial mechanism was elucidated by analyzing the integrity of bacterial biofilms.Antibacterial activity was evaluated via the zone of inhibition assay.Cytotoxicity testing was performed using the cell counting kit-8(CCK-8) assay,and combined with the cell scratch assay,to collectively evaluate the effects of the hydrogel on cellular biocompatibility and migration ability.Results The water loss rate and water vapor transmission rate of PA/BSPH hydrogel were(32.3±2.3) % and(2 228.2±181.1) g/(m2·d).Compared with the H group hydrogel,the contents of hydrogen peroxide(H_2O2) and hydroxyl radicals(·OH) in PAH and PA/BSPH groups significantly increased(P 2 and·OH in PAW.The incorporation of BSP enhances the water retention and breathability of the wound dressing while significantly reducing the cytotoxicity of PAW.This modification endows the hydrogel with improved biocompatibility and promotes cell proliferation.The PA/BSPH hydrogel demonstrates clinical potential by offering a novel therapeutic strategy for chronic infected wound management.