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A promising strategy for lipase immobilization based on the natural polymers of polysaccharides (hyaluronan (HA) and chitosan (CHI)) functionalized magnetic microspheres (Fe3O4@SiO2@{CHI/HA}3) was developed. First, Fe3O4 magnetic microspheres and Fe3O4@SiO2 core/shell microspheres were synthesized by hydrothermal reaction and sol–gel method, respectively. Owing to the abundant carboxyl groups in HA chains, the lipase was covalently bonded on the surface of the polysaccharide-functionalized magnetic supports by ultilizing 1-ethyl-3-(3-(dimethylamino)-propyl) carbodiimide and N-hydroxysuccinimide chemistry to produce robust biocatalysts of Fe3O4@SiO2@{CHI/HA}3@lipase. The morphology, core–shell structure, and magnetic property of the supports and immobilized lipase were investigated through various analytical techniques, including FT-IR analysis, transmission electron microscopy, scanning electron microscopy equipped with energy dispersive spectrometer, elemental analysis, vibrating sample magnetometer, thermogravimetric analysis, and X-ray diffraction. Consequently, the magnetic Fe3O4@SiO2@{CHI/HA}3 microspheres exhibited a superior performance in terms of immobilizing lipase. The magnetic immobilized lipase showed good thermal and long-term stability, reusability, and catalytic activity for the synthesis of the structured lipid of 1,3-dioleoyl-2-palmitoylglycerol (OPO), which has recently received much interest as a healthy component of food, oil, and pharmaceutical intermediates. The magnetic immobilized lipase could be considered a green and sustainable biocatalyst for the highly efficient synthesis of OPO.

Postsurgical peritoneal adhesions are a common and serious postoperative complication after various peritoneal surgeries, such as pelvic and abdominal surgery. Various studies have shown that peritoneal adhesions can be minimized or prevented by physical antiadhesion barriers, including membranes, knits, and hydrogels. Hydrogels have attracted great attention in preventing peritoneal adhesions because the dimensional architecture of hydrogels is similar to that of the native extracellular matrix. However, chemical cross-linkers had to be used in the preparation of chemical hydrogels, which may have problems in cytotoxicity or unwanted side effects. This fact prompts us to create alternative cross-linking methods for the development of biocompatible hydrogels as physical barriers. Herein, we report a physically cross-linked flexible hyaluronan (HA) cryogel prepared via a freeze−thaw technique as a novel anti-adhesion biomaterial for completely preventing postsurgical peritoneal adhesions. In vitro studies demonstrated that this physically cross-linked HA cryogel exhibited excellent biocompatibility, the inherently desirable biocompatibility and functionality of HA being integrally retained as much as possible. Intriguingly, the rheological properties and appropriate biodegradability of the cryogels were readily tailored and tunable by way of the gelation process. In vivo assessments suggested that the cryogel, as a physical barrier, satisfactorily prevented fibroblast penetration and attachment between the injured tissues and nearby normal organs. Furthermore, the molecular mechanism studies revealed that the HA cryogel could prevent peritoneal adhesion by inhibiting inflammatory response and modulation of the fibrinolytic system. Our results show that HA ultrasoft cryogel is a promising clinical candidate for prolonged adhesion prevention.