Bifunctional　periodic　mesoporous　organosilicas　(PMOs)　with　ethane　bridging　groups　within　the　framework　and　various　amounts　of　terminally　bonded　groups　in　the　pore　channels　was　synthesized　by　the　co-condensation　of　1,2-bis(triethoxysilyl)ethane　(BTESE)　and　3-glycidoxypropyltrimethoxylsilane　(GPTMS)　in　the　presence　of　triblock　copolymer　poly(ethylene　glycol)-b-poly(propylene　glycol)-b-poly(ethylene　glycol)　(P123)　surfactants　under　acidic　conditions　and　utilized　as　supports　for　enzyme　immobilization　It　is　revealed　that　glycidoxypropyl　groups　have　been　successfully　covalently　attached　to　the　pore　wall　of　PMOs　and　a　fraction　of　them　have　experienced　epoxy　ring　opening　reaction　to　form　diol　groups.　The　functional　materials　still　preserve　a　mesoscopic　ordering　at　a　concentration　of　GPTMS　as　high　as　10%　in　the　reaction　mixtures　The　BET　surface　area,　pore　volume　and　pore　size　of　the　functionalized　materials　decrease　with　increasing　amount　of　GPTMS,　but　a　desirable　pore　structure　remains　when　the　GPTMS　amount　Increases　to　10%　The　coexistence　of　the　epoxy　groups　and　the　diol　groups　provides　an　efficient　two-step　covalent　enzyme　immobilization　mechanism.　The　bifunctional　PMOs　materials　exhibit　higher　papain　immobilization　efficiency　and　stability　than　pure　PMOs　because　of　the　covalent　interaction　between　the　amino　groups　of　papain　and　the　epoxy　groups　of　functionalized　PMOs　(C)　2010　Elsevier　Inc　All　rights　reserved.