Herein, the immobilization of α–amylase onto hydroxyapatite (HA) and hydroxyapatite-decorated ZrO₂ (10%wt) (HA-ZrO₂) nanocomposite were investigated. The immobilization yield was 69.7% and 84% respectively. The structural differences were characterized using X-Ray diffraction, attenuated total reflectance-Fourier transform infrared spectra, Raman, and scanning electron microscope. After 10 repeated cycles, the residual activity of immobilized α–amylase onto HA and HA-ZrO₂ nanocomposite was 46% and 70%, respectively. The storage stability was recorded to be 27%, 50% and 69% from its initial activity in the case of free and immobilized enzyme onto HA and HA-ZrO₂ nanocomposite, respectively after 8 weeks. The pH-activity profile and temperature revealed pH 6.0 and temperature 50 °C as the optimal values of free α-amylase, while the optimum values for α-amylase on HA and HA-ZrO₂ was shifted to pH 6.5 and 60 °C after immobilization. The immobilized α-amylase onto HA-ZrO₂ showed comparatively higher catalytic activity than the free α-amylase. The Km value after the immobilization process onto HA was 2.1 folds highly than that of the free enzyme. In conclusion, it can be inferred that HA-ZrO₂ is more sustainable and beneficial support for enzyme immobilization and it represents promising supports for different uses of α–amylase in the biomedical applications.

本文研究了α-淀粉酶在羟基磷灰石（HA）和修饰羟基磷灰石修饰的ZrO ₂（10％wt）（HA-ZrO ₂）纳米复合材料上的固定化作用。固定化率分别为69.7％和84％。使用X射线衍射，衰减的全反射-傅立叶变换红外光谱，拉曼和扫描电子显微镜表征结构差异。经过10个重复循环，固定在HA和HA-ZrO ₂纳米复合材料上的α-淀粉酶的残留活性分别为46％和70％。在游离和固定化酶到HA和HA-ZrO ₂的情况下，记录的储藏稳定性比其初始活性分别高出27％，50％和69％。纳米复合材料，分别在8周后。pH活性曲线和温度显示，游离α-淀粉酶的最佳值为pH 6.0和温度50°C，而HA和HA-ZrO ₂上α-淀粉酶的最佳值在转移后分别移至pH 6.5和60°C固定。与游离α-淀粉酶相比，固定在HA-ZrO ₂上的α-淀粉酶显示出较高的催化活性。所述ķ固定化过程到HA之后米值比游离酶的2.1倍的高度。总之，可以推断出HA-ZrO ₂是酶固定化的更可持续和有益的支持，它代表了在生物医学应用中对α-淀粉酶的不同用途的有希望的支持。