A novel approach termed the "concentrated method" was developed for the instant fabrication of laccase@Co3(PO4)2•hybrid nanoflowers (HNFs). The constructed HNFs were obtained by optimizing the concentration of cobalt chloride and phosphate buffer to reach the highest activity recovery. The incorporation of 30 mM CoCl2 and 160 mM phosphate buffer (pH 7.4) resulted in a fast anisotropic growth of the nanomaterials. The purposed method did not involve harsh conditions and prolonged incubation of precursors, as the most reported approaches for the synthesis of HNFs. The catalytic efficiency of the immobilized and free laccase was 460 and 400 M−1S−1, respectively. Also, the enzymatic activity of the prepared biocatalyst was 113% of the free enzyme (0.5 U mL−1). The stability of the synthesized HNFs was enhanced by 400% at pH 6.5–9.5 and the elevated temperatures. The activity of laccase@Co3(PO4)2•HNFs declined to 50% of the initial value after 10 reusability cycles, indicating successful immobilization of the enzyme. Structural studies revealed a 32% increase in the α-helix content after hybridization with cobalt phosphate, which improved the activity and stability of the immobilized laccase. Furthermore, the fabricated HNFs exhibited a considerable ability to remove moxifloxacin as an emerging pollutant. The antibiotic (10 mg L−1) was removed by 24% and 75% after 24 h through adsorption and biodegradation, respectively. This study introduces a new method for synthesizing HNFs, which could be used for the fabrication of efficient biocatalysts, biosensors, and adsorbents for industrial, biomedical, and environmental applications.

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Organic-inorganic hybrid nanoflowers (HNFs) have been synthesized by soft biomineralization procedures and are mainly used in biocatalysis and biosensing. Previously-reported methods for the synthesis of HNFs have so far required a 3-day incubation, bath sonication, or shear stress tension, which possibly introduces damage to the organic component. In this study, a novel method for instant fabrication of laccase@Co3(PO4)2•HNFs was developed without using harsh conditions. The prepared HNFs were assembled instantly by the “concentrated method,” which resulted in the fast growth of the flower-shaped nanostructures by a higher collision rate of the primary nucleation sites. The obtained results indicated that catalytic efficiency and enzymatic activity of laccase@Co3(PO4)2•HNFs were 113% and 110%, respectively, compared to the free enzyme. Also, the stability of the immobilized enzyme was enhanced by 400% in basic pH values. The activity of laccase@Co3(PO4)2•HNFs declined to 50% of the initial value after 10 reusability cycles, indicating successful immobilization of the enzyme. Structural studies revealed a 32% increase in the α-helix content after hybridization with cobalt phosphate, which improved the activity and stability of the immobilized laccase. Furthermore, the fabricated HNFs exhibited a considerable ability to remove moxifloxacin as an emerging pollutant. The antibiotic (10 mg/L) was removed by 24% and 75% after 24 h through adsorption and biodegradation mechanisms, respectively. This study introduces a new method for synthesizing HNFs, which could be used for the instant fabrication of efficient biocatalysts, biosensors, and adsorbents to be potentially employed in industrial, biomedical, and environmental applications.