Alkaline phosphatase-induced gelation and biomimetic mineralization of silk protein solution

Abstract

The invention discloses a method for alkaline phosphatase to induce gelation and biomimetic mineralization of silk protein solution. The invention introduces a small molecule polypeptide that is sensitive to ALP and has good biocompatibility and self-assembly properties as a gelling factor The precursor, which can remove the phosphate group on the molecule under the catalysis of ALP to generate NY, triggers supramolecular self-assembly, thereby synergistically inducing SF co-self-assembly, and finally leads to the rapid formation of SF hydrogel. The ALP encapsulated in the SF‑NY hydrogel network still maintains its catalytic activity and induces the formation of apatite minerals in the gel by catalyzing β‑glycerophosphate to release free phosphate ions. Due to the mild gelation process and the formation of apatite minerals in the gel matrix, the biomimetic mineralized SF gel could not only be used as a biomimetic scaffold to promote the adhesion of rat BMSCs in vitro, Proliferation and osteogenic differentiation, and can also promote natural healing of femoral defects in a rat model.

Description

technical field [0001] The invention relates to a method for inducing gelation and bionic mineralization of silk protein solution by alkaline phosphatase, which belongs to the field of material technology. Background technique [0002] In nature, the biomineralization process is affected by many organic components, including proteins, polysaccharides, and enzymes, which play an important role in regulating the growth of hydroxyapatite crystals. During natural bone formation, alkaline phosphatase (ALP) secreted by osteoblasts increases the local phosphate concentration by releasing inorganic phosphate ions from organophosphate, prompting hydroxyapatite (HA ) mineralization. In the water environment, alkaline phosphatase (alkalinephosphatase) can catalyze the removal of the phosphate group on the substrate molecule, so that the hydrophobicity of the substrate is enhanced. In 2004, Xu et al. reported for the first time that under the catalysis of alkaline phosphatase, the sub...

AI Technical Summary

Problems solved by technology

[0004] However, these traditional methods still face some challenges and deficiencies when they are applied in clinical medicine.

For example, when the rapid gelation of silk protein solution is induced by physical methods such as ultrasonic treatment, swirling shear and electrification, the gelation process under non-physiological conditions triggered by electronic instruments does not match the clinical medical environment

Although the gelation time of silk protein was shortened to a certain extent by adding organic reagents, inorganic compound, ionic liquid, high-pressure carbon dioxide, surfactants and synthetic polymers to the silk protein solution, this series The gelation process is incompatible with some clinical use environments, such as the potential cytotoxicity of organic molecules, the biological inertness of high molecular polymers, and the disadvantages of being difficult to degrade in vivo

In addition, although scientists also use poly(ethylene glycol diglycidyl ether) (PGDE), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC), geni Ping, chloroauric acid, etc. are used as chemical cross-linking agents to obtain silk protein gel materials with good mechanical strength and stability, but the potential cytotoxicity of the remaining chemical cross-linking agents in the system affects the biological properties of silk protein gel materials. compatibility

In summary, although these measures can shorten the gelation time of silk protein to a certain extent, the obtained silk protein gel material has poor biocompatibility and high cytotoxicity. These problems lead to its application in biomedical materials. The application of the aspect is greatly limited

Images