## 2 Organic-Inorganic Hybrid Nanofibers
### Combination of Hybridized HNFs with Other Immobilization Methods  
Despite the many advantages of HNFs, their structure, characterized by numerous fragile petal-like structures, is prone to breakage during processes such as stirring or centrifugation, leading to structural fragility [80]. This mechanical instability limits their reusability and application in the field of biocatalysis [81]. Scientists have addressed this issue by enhancing the mechanical strength of HNFs through the introduction of connections between petals, resulting in the synthesis of efficient, durable, and recyclable HNFs. Natural biopolymers such as gelatin (Ge) and chitosan (CS) possess an ample number of amino and hydroxyl groups, serving as nucleation points for crystal formation. They reduce the nucleation barrier of crystal formation and promote the heterogeneous nucleation process of inorganic minerals [82], achieving controlled mineralization. The regulation of biomineralization by natural biopolymers represents a promising immobilization method characterized by excellent stability and recyclability. [PERSON] et al. utilized the natural biopolymer CS to regulate the biomimetic mineralization of calcium phosphate (CaP). Through self-assembly, they immobilized sucrose phosphorylase (SPase), creating a novel type of HNF with excellent stability and catalytic activity: CS-CaP@SPase (Figure 4). Even after 10 cycles, the relative activity of CS-CaP@SPase remained around 80%, and after 15 days, it maintained a relative activity of approximately 75% [82]. The incorporation of carbon nanotubes (CNTs) into HNFs can enhance the mechanical strength of the nanoflowers and provide additional accessible adsorption binding sites, effectively improving enzyme activity. [PERSON] et al. synthesized HRP-NF@CNTs composed of horseradish peroxidase (HRP), Cu\({}^{2+}\), and CNTs using an in situ method. Due to the synergistic integration of CNTs and Cu\({}_{3}\)(PO\({}_{4}\))\({}_{2}\) crystals, HRP-NF@CNTs exhibited outstanding peroxidase-like activity and stability. Compared to HRP-NF, HRP-NF@CNTs also demonstrated excellent stability after 10 cycles. Furthermore, compared to free HRP, the kinetic parameters of HRP-NF@CNTs were improved, with a reduction in the Km value by 18.05 times [83]. [PERSON] et al. coupled amine-functionalized Fe\({}_{3}\)O\({}_{4}\) magnetic nanoparticles (MNPs) with glucose oxidase (GOx) molecules, followed by the addition of Cu\({}_{3}\)(PO\({}_{4}\))\({}_{2}\) to prepare embedded MNPs-GOx NFs. MNPs-GOx NFs exhibited excellent peroxidase-like activity and demonstrated more sensitive glucose detection activity compared to MNPs mixed  
Figure 4: Schematic illustration of the preparation process of the CS-CaP@SPase [82]. with free GOx. The close proximity between MNPs and Cu\({}_{3}\)(PO\({}_{4}\))\({}_{2}\) crystals facilitated the accumulation of H\({}_{2}\)O\({}_{2}\) molecules produced during the catalysis of glucose oxidation by GOx, creating a substrate channel environment that enhanced catalytic activity. MNPs-GOx NFs prepared through this strategy demonstrated excellent selectivity, stability, and magnetic reusability [84]. For cofactor-dependent reactions, the recycling of expensive cofactors is crucial for implementing enzyme catalysis at an industrial scale. The immobilization of cofactors is considered an effective strategy to address these challenges. [PERSON] and colleagues pioneered the co-immobilization of omega-transaminase (\(\omega\)-ta) and 5\({}^{\prime}\)-pyridoxal phosphate (PLP) within Co\({}_{3}\)(PO\({}_{4}\))\({}_{2}\) nanoflowers, creating a novel self-sufficient biocatalyst, \(\omega\)-TA-PLP@Co\({}_{3}\)(PO\({}_{4}\))\({}_{2}\). In comparison to free \(\omega\)-ta, \(\omega\)-TA-PLP@Co\({}_{3}\)(PO\({}_{4}\))\({}_{2}\) demonstrated higher catalytic efficiency, stability, storage stability, and repeatability [56].