Hybrid Organic-Inorganic Nanoflowers as Efficient Supports for Lipase Immobilization

Lipases are versatile biocatalysts widely used in the food, pharmaceutical, and biofuel industries, but their free form exhibits low stability and limited reusability. In this study, we present an innovative approach for the immobilization of the commercial lipase Lipozyme TL in hybrid organic–inorganic nanoflowers synthesized with two distinct metallic salts (CuSO₄ and CaCl₂). Unlike previous works, this is the first study to conduct a systematic comparative evaluation between these two supports, combining structural, kinetic, and thermodynamic characterizations to elucidate the mechanisms of enzymatic stabilization. In addition, we demonstrate an optimized synthesis route, enabling the preparation of CaCl₂ nanoflowers in just 3 h, significantly reducing the time compared to the conventional method (24 h), which represents an advance in terms of practical applicability. The results show that the immobilized lipases exhibited up to twice the activity of the free enzyme (409.68 U/g in CaCl₂ vs. 210.55 U/g), high thermal stability (retaining > 80% activity after prolonged exposure at 50–70 °C), and excellent reusability (up to 14 cycles in the case of CuSO₄). Thermodynamic analysis confirmed greater structural robustness, with positive ΔG and negative ΔS values, indicating lower propensity to denaturation. These findings highlight the potential of hybrid nanoflowers as robust and economically viable platforms for industrial processes that require reusable and thermally stable biocatalysts.

Graphical Abstract