Polysilicate-polysilicone enzyme immobilization materials

Abstract

The present invention generally relates to improvements in enzyme immobilization, particularly for use in the field of carbon dioxide capture and sequestering. It has been discovered that the utilization of sol-gel processes to immobilize enzymes in polysilicate-polysilicone copolymer coatings and particles, and the deposition of these coatings on solid state supports or use of suspensions of these particles, provides significant benefits for use in industrial applications involving enzymatic catalysts.

1 .- 97 . (canceled) 
     
     
         98 . An immobilized enzyme comprising
 an enzyme; and   an immobilization material;   wherein the enzyme is entrapped within the immobilization material and the immobilization material is derived from reaction of a sol, the sol comprising (i) an alkoxy silane or an organotrialkoxy silane or metasilicate, (ii) a poly(silicone), and (iii) an enzyme.   
     
     
         99 . The immobilized enzyme of  claim 98  wherein the poly(silicone) comprises a poly(siloxane). 
     
     
         100 . The immobilized enzyme of  claim 98  wherein the sol further comprises a hydrophilic additive. 
     
     
         101 . The immobilized enzyme of  claim 100  wherein the sol further reacts with a catalyst. 
     
     
         102 . The immobilized enzyme of  claim 98  wherein the enzyme comprises a lipase, a glucose isomerase, a nitrilase, a glucose oxidase, a protease, a carbonic anhydrase, a pepsin, an amylase, a fungal amylase, a maltogenic amylase, a cellulase, a lactase, an esterase, a carbohydrase, a hemicellulase, a pentosanase, a xylanase, a pullulanase, a β-glucanase, an acetolactate decarboxylase, a β-glucosidase, a glutaminase, a penicillin acylase, a chloroperoxidase, an aspartic β-decarboxylase, a cyclodextrin glycosyltransferase, a subtilisin, an aminoacylase, an alcohol dehydrogenase, an amino acid oxidase, a phospholipase, a urease, a cholesterase, a desulfinase, a lignin peroxidase, a pectinase, an oxidoreductase, a dextranase, a glucosidase, a galactosidase, a glucoamylase, a maltase, a sucrase, an invertase, a naringanase, a bromelain, a ficin, a papain, a pepsin, a peptidase, a chymosin, a thermolysin, a trypsin, a triglyceridase, a pregastric esterase, a phosphatase, a phytase, an amidase, a glutaminase, a lysozyme, a catalase, a dehydrogenase, a peroxidase, a lyase, a fumarase, a histadase, an aminotransferase, a ligase, a cyclase, a racemase, a mutase, an oxidase, a reductase, a ligninase, a laccase, a chloroperoxidase, a haloperoxidase, a hydrogenase, a nitrogenase, an oxynitrilase, or a combination thereof. 
     
     
         103 . The immobilized enzyme of  claim 102  wherein the enzyme is a carbonic anhydrase. 
     
     
         104 . The immobilized enzyme of  claim 101  wherein the enzyme is a carbonic anhydrase. 
     
     
         105 . The immobilized enzyme of  claim 98  wherein the alkoxy silane is tetramethylorthosilicate, tetraethylorthosilicate, methyltriethylorthosilicate, ethyltrimethylorthosilicate, dimethyldiethylorthosilicate, tetraglyceryl silicate, or a combination thereof. 
     
     
         106 . The immobilized enzyme of  claim 98  wherein the organotrialkoxy silane is trimethoxymethylsilane, trimethoxyethylsilane, or a combination thereof. 
     
     
         107 . The immobilized enzyme of  claim 98  wherein the alkoxy silane comprises tetramethylorthosilicate. 
     
     
         108 . The immobilized enzyme of  claim 98  wherein the poly(silicone) is a poly(siloxane) selected from the group consisting of poly(dimethylsiloxane), poly(dimethylsiloxane)-co-poly(alkene oxide), or a combination thereof. 
     
     
         109 . The immobilized enzyme of  claim 108  wherein the poly(siloxane) comprises poly(dimethylsiloxane). 
     
     
         110 . The immobilized enzyme of  claim 108  wherein the poly(silicone) is silanol-terminated. 
     
     
         111 . The immobilized enzyme of  claim 100  wherein the hydrophilic additive is poly(vinyl alcohol), poly(ethylene oxide), a quaternary ammonium polymer, a crown ether, a cyclodextrin, a surfactant, hexadecyltrimethylammonium bromide, poly(1-methyl-4-vinylpyridinium bromide), poly(acrylamide-methacryloxyethyltrimethylammonium bromide), or a combination thereof. 
     
     
         112 . The immobilized enzyme of  claim 111  wherein the crown ether is 12-crown-4, 1,7-diaza-12-crown-4, 1,4,8,11-tetrathiacyclotetradecane, 1,4,8,12-tetraazacyclopentadecane, 15-crown-5,18-crown-6, dibenzo-18-crown-6, dicyclohexano-18-crown-6, (18-crown-6)-2,3,11,12-tetracarboxylic acid, 1-aza-18-crown-6, diaza-18-crown-6, or a combination thereof. 
     
     
         113 . The immobilized enzyme of  claim 112  wherein the crown ether comprises 18-crown-6. 
     
     
         114 . The immobilized enzyme of  claim 100  wherein the alkoxy silane comprises tetramethylorthosilicate, the poly(siloxane) comprises polydimethylsiloxane, and the hydrophilic additive comprises a crown ether. 
     
     
         115 . The immobilized enzyme of  claim 98  wherein the molar ratio of alkoxy silane or organotrialkoxy silane or metasilicate to poly(silicone) is from about 2:1 to about 8:1. 
     
     
         116 . A process for removing CO 2  from a CO 2 -containing gas, the process comprising
 contacting a liquid with a CO 2 -containing gas; and contacting the CO 2  in the liquid with the immobilized enzyme of  claim 104  to catalyze hydration of the CO 2  and form a treated liquid comprising hydrogen ions and bicarbonate ions.   
     
     
         117 . A system for removing CO 2  from a CO 2 -containing gas comprising a reaction vessel comprising a bottom portion containing a gas inlet and a liquid outlet, a top portion containing a liquid inlet and a gas outlet, and a middle portion containing a plurality of the immobilized enzymes of  claim 103 , the carbonic anhydrase being capable of catalyzing hydration of CO 2  into hydrogen ions and bicarbonate ions.