Jack bean urease, the first nickel metalloenzyme, and crystallized enzymes have historical significance due to their several applications in the biomedical and other fields. For the first time, cross-linker free pH-responsive hydrogel–urease bioconjugates have been reported. Without the use of divinyl benzene or divinyl acrylamide derivatives, urease was immobilized inside the hydrogel matrix and various grades of bioconjugates were synthesized. The hydrogel–urease bioconjugate exhibits excellent swelling–deswelling and pH-responsive characteristics without affecting the urease enzyme. The pH-responsive bioconjugates were characterized by FT-IR, powder XRD, SEM, TGA, and UV-vis spectroscopy. Urea hydrolysis and enzyme affinity have been investigated at pH 4, pH 7, and pH 11 using bioconjugates and free urease. At basic pH, BCs showed excellent enzyme activity. In summary, this technique is effective for stabilizing biomacromolecules at different pHs for a variety of real applications.

中文翻译：

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新设计的基于丙烯酰胺衍生物的 pH 响应水凝胶-尿素酶生物共轭物：合成和催化尿素水解

刀豆脲酶、第一种镍金属酶和结晶酶因其在生物医学和其他领域的多种应用而具有历史意义。首次报道了无交联剂的 pH 响应水凝胶-尿素酶生物偶联物。在不使用二乙烯基苯或二乙烯基丙烯酰胺衍生物的情况下，将脲酶固定在水凝胶基质内，并合成了各种等级的生物偶联物。水凝胶-尿素酶生物偶联物在不影响尿素酶的情况下表现出优异的溶胀-消溶胀和 pH 响应特性。通过 FT-IR、粉末 XRD、SEM、TGA 和紫外-可见光谱对 pH 响应性生物缀合物进行了表征。使用生物共轭物和游离脲酶在 pH 4、pH 7 和 pH 11 下研究了尿素水解和酶亲和力。在碱性 pH 值下，BC 表现出优异的酶活性。总之，该技术可有效稳定不同 pH 值下的生物大分子以用于各种实际应用。