Enzymes are nearly perfect catalysts with excellent selectivity and high turnover frequencies. A long-standing goal has been enabling enzymes to operate ex vivo in non-aqueous solvents, but the structures of native enzymes are typically compromised under these conditions. Polymer-enzyme bioconjugates have shown some promise-albeit limited-in this regard. The clickable poly(propargyl methacrylate) (PPMA) was proposed as a platform to enhance different polymer structures versus the residual enzymatic activities. The degree of polymerization and polydispersity are two factors that affect the polymer properties and can affect the enzymatic activities of the polymer-enzyme bioconjugates. The literature examples of PPMA with degree of polymerization greater than 200 are limited. In the atom transfer radical polymerization (ATRP) conditions we discovered, the degree of polymerization and the polydispersity of poly(trimethylsilylpropargyl methacrylate) (PTMSPMA) can be precisely adjusted by the initiator and monomer ratio, the copper catalyst loading, and the reducing agent loading (copper wire). After deprotection, PPMA is further reacted with different mole fraction compositions of hydrophilic triethylene glycol monomethyl ether (mDEG) azide and hydrophobic dodecyl azide to prepare amphiphilic polymers as enzyme stabilizers. The activities of the model enzyme, Subtilisin Carlsberg (SC), and polymer-SC bioconjugates were determined by 4-nitrophenolate and 4-thiopyridone assays, and the polymer-enzyme bioconjugate SC 82%mDEG-PPMA was found to be more active than SC alone in toluene. The SC 82%mDEG-PPMA is also more active than SC 100%mDEG-PPMA in 4-nitrophenolate assay, proving that the side chain structure of the polymer micelles can affect the polymer-enzyme bioconjugates. The micelle 80%mDEG-PPMA may isolate the enzyme from the bulk toluene better than 100%mDEG-PPMA. Deprotonated amino acid salts are great alternatives to the synthesized alkylamines as post-combustion CO2 absorbents due to their non-toxic and low volatile nature. For CO2 capture, gas uptake was measured when solutions of monodeprotonated amino acids were sparged with CO2. The speciation between dissolved CO32-, HCO3-, and CO2(aq), and CO2 captured as carbamates of the deprotonated amino acids, was quantified by 13C{1H} and 1H NMR spectroscopy. Less hindered amino acids like glycine tend to have faster CO2 absorption kinetic and higher carbamate concentrations due to the formation of relatively stable carbamates. One equivalent of carbamate forms requires one equivalent of amino acid as sacrificial base. Therefore, the formation of carbamate decreases the total CO2 absorption capacity and is an unfavorable pathway for CO2 capture. While the amino acids containing substituents at the Îł carbon atom adjacent to the amino group, like alanine and proline, destabilize their carbamates by unfavorable steric interaction and lead to carbamate hydrolysis to CO32-/HCO3- and enhance the CO2 capture capacity. Therefore, mixing different amino acids can have the fast absorption kinetics and higher absorption capacity. Based on the results, the mixture amino acid solutions were observed to have higher CO2 absorption capacity than the single amino acid counterparts.
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