Chitosan/gelatin and chitosan/gelatin/nanohydroxyapatite hydrogels were rapidly and stably prepared without any crosslinking materials by using an engineered tyrosinase (mTyr-CNK) with high catalytic activity for tyrosine/DOPA-tethered polymeric biomaterials throughout a broad pH range. A dual-barrel syringe with one part containing chitosan/mTyr-CNK solution and the other containing gelatin solution with/without nanohydroxyapatite was successfully used to form homogeneous hydrogels at room temperature followed by 37 °C to simulate an in situ injection approach. The obtained hydrogels exhibited an average pore size greater than 150 µm and high swelling ratios with similar mechanical properties to other chemically crosslinked chitosan/gelatin hydrogels. The in vitro degradation properties and cellular viability suggested that the hydrogels could be used as biodegradable and biocompatible scaffolds for biomedical applications, such as space filling biomaterials and delivery vehicles for bioactive molecules and cells. These results demonstrated that mTyr-CNK-mediated hydrogels have remarkable promise as an injectable scaffold biomaterial.

中文翻译：

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酪氨酸酶介导的快速和永久壳聚糖/明胶和壳聚糖/明胶/纳米羟基磷灰石水凝胶

壳聚糖/明胶和壳聚糖/明胶/纳米羟基磷灰石水凝胶在没有任何交联材料的情况下通过使用对酪氨酸/多巴连接的聚合物生物材料具有高催化活性的工程酪氨酸酶（mTyr-CNK）在很宽的pH范围内快速稳定地制备。一个双管注射器，一部分含有壳聚糖/mTyr-CNK 溶液，另一部分含有含有/不含纳米羟基磷灰石的明胶溶液，成功用于在室温下形成均匀的水凝胶，然后在 37°C 下模拟原位注射方法。所得水凝胶的平均孔径大于 150 µm，具有与其他化学交联壳聚糖/明胶水凝胶相似的机械性能和高溶胀率。体外降解特性和细胞活力表明，水凝胶可用作生物医学应用的可生物降解和生物相容性支架，例如空间填充生物材料和生物活性分子和细胞的递送载体。这些结果表明，mTyr-CNK 介导的水凝胶作为可注射支架生物材料具有显着的前景。