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Amphoteric diblock copolymers (S10Vn, n = 5, 10, and 20) composed of anionic poly(sodium p-styrenesulfonate) and cationic poly(vinylbenzyl trimethylammonium chloride) blocks were prepared via a controlled radical polymerization method. S10V10 was insoluble in pure water owing to its electrostatic interactions, but S10V5 and S10V20 were soluble in pure water. S10V5 and S10V10 exhibited upper critical solution temperature behaviors, and the transition temperature decreased with increasing sodium chloride concentration. [ABSTRACT FROM AUTHOR]

Horseradish peroxidase (HRP) is a kind of enzyme commonly used in clinical trials that is rich in the plant horseradish. It has a wide range of applications in the fields of pharmacy and pollution control. However, free enzymes are easily denatured and inactivated by environmental influences, which is not conducive to the normal progress of the reaction. At the same time, the cost of enzymes is relatively high, and it is difficult to separate and recover during the reaction. In this study, the UCST-type temperature- responsive polymer was combined with HRP under the optimal immobilization reaction conditions of 3% polymer solution concentration, 60 ℃, and pH= 8 through affinity interaction to produce UCST-type smart polymerase. The smart polymerase has stronger temperature stability, pH stability and storage stability than free enzymes. In the simulated pollutant degradation experiment, under the molar ratio of phenol to H 2 O 2 is 1:1, the temperature of 60 ℃, and pH= 7, smart polymerase can degrade 91% of phenol in a 100 mg/L phenol solution within 1 h. After five cycles of catalytic reaction, 68% of smart polymerase was recovered through cooling precipitation. In the phenol degradation experiments of two different real water samples, 88% and 90% of the phenol in the water were removed, respectively, and most of the highly active immobilized enzymes were recovered at the same time. Finally, the biotoxicity of the catalyzed reaction product is significantly reduced was demonstrated. [Display omitted] • A new UCST-type temperature-sensitive polymer P (NAGA-b-VBA) was synthesized, and the mechanism of its UCST behavior has been explored. • P (NAGA-b-VBA) combined with horseradish peroxidase to form a smart polymerase with UCST properties. • The immobilized HRP can be dissolved in water and substrate for high-speed liquid-liquid phase catalysis at high temperature, and it can be easily precipitated and recovered at low temperature. • The immobilized HRP has better temperature stability, pH stability, storage stability and operational stability than free enzyme. • The immobilized HRP can catalyze phenol in actual water samples, and the biological toxicity of the catalytic product is greatly reduced. [ABSTRACT FROM AUTHOR]

Upper critical solution temperatures (UCSTS ± 0.05 K) and mutual solubilities of phenol + water systems are reported separately with 0.5 millimol kg-1 (mm kg-1) proteins (casein, pepsin, egg-albumin), vitamins (B1-thiamine, B2-riboflavin, B6-pyridoxine), amino acids (glycine, β-alanine, L-leucine) and surfactants (dodecyl trimethylammonium bromide- DTAB, trimethylsulphoxonium iodide-TMSOI, methyltrioctylammonium chloride- MTOAC, orcinol). The additives decrease the UCSTs by about 0.50-2 °C with slight enhancement in mutual solubilities but the leucine with two -CH3 (methyl) and two - CH2- (methylene) groups produce negligible increase in the solubilities. The -CH3 and - CH2- groups develop stronger hydrophobic interactions but the glycine develops stronger hydrophilic interactions due to -N+H3 (amino) and -COO- (carboxylic) groups and weaker hydrophobic due to single -CH2- group. The leucine increases the solubility by 0.009 mole fractions with a 0.7 °C decrease in USCT as compared to phenol-water. The mole fractions of additives restricted to 0.002 to 0.005 range, the conjugations of casein and vitamins in place of -CH3 groups of amino acids enhance the solubility with lower UCST values. [ABSTRACT FROM AUTHOR]