CN-121971380-A - Injectable double-drug delivery hydrogel and preparation method thereof

CN121971380ACN 121971380 ACN121971380 ACN 121971380ACN-121971380-A

Abstract

The invention discloses injectable double-drug delivery hydrogel and a preparation method thereof, and belongs to the technical field of biomedical materials. According to the method, two kinds of nano microspheres with different charges are prepared by utilizing the characteristics of the type A gelatin and the type B gelatin, the positively charged medicine EGCG is specifically carried by the positively charged type A gelatin, the positively charged medicine SAG is carried by the negatively charged type B gelatin microsphere, and finally the two kinds of gelatin medicine carrying microspheres are mixed into a material with gelatin and zirconium ions as substrates to form the composite hydrogel. The hydrogel realizes immune regulation and bone formation regulation, also realizes long-acting release of two medicines, effectively solves the problems of bone resorption, difficult healing and the like of host tissues by cooperatively regulating inflammation and mobilizing bone formation genes, realizes personalized treatment and improves clinical treatment effect and efficiency.

Inventors

LI JIDONG
QIN ZHENGYANG
WANG JUN
YANG QIAN
XIE XUDONG
LI YUBAO

Assignees

四川大学

Dates

Publication Date: 20260505
Application Date: 20260403

Claims (10)

1. A method for preparing an injectable dual drug delivery hydrogel, comprising the steps of: s1, dissolving type A gelatin in deionized water, adjusting the pH to 7.6-10 to obtain a solution I, and adding the solution I into absolute ethyl alcohol in an ultrasonic state to obtain a solution II; S2, dissolving the type B gelatin in deionized water, adjusting the pH to 5-7.5 to obtain a solution III, and adding the solution III into absolute ethyl alcohol in an ultrasonic state to obtain a solution IV; s3, mixing 25% glutaraldehyde, absolute ethyl alcohol and water to obtain a solution V; s4, adding the second solution and the fourth solution into the fifth solution respectively, stirring for 3 hours, and standing for 12 hours to obtain a first suspension and a second suspension; S5, regulating the pH value of the suspension to 7, centrifuging, washing the precipitate with absolute ethyl alcohol, and drying the precipitate to obtain the gelatin microsphere A; S6, regulating the pH value of the suspension to 7, centrifuging, washing the precipitate with absolute ethyl alcohol, and drying the precipitate to obtain the gelatin microsphere B; S7, adding the type A gelatin microspheres into the EGCG solution, stirring, adding the type B gelatin microspheres into the SAG solution, stirring, and respectively centrifuging and drying to obtain type A gelatin microspheres carrying EGCG and type B gelatin microspheres carrying SAG; And S8, adding the EGCG-loaded type A gelatin microspheres and the SAG-loaded type B gelatin microspheres into the matrix gelatin solution, stirring and dispersing uniformly to obtain a precursor solution, and adding a cross-linking agent into the precursor solution to obtain the injectable double-drug delivery hydrogel.
2. The method of preparing an injectable dual drug delivery hydrogel of claim 1, wherein the A-type gelatin jelly strength is greater than or equal to 260 Bloom g and greater than or equal to 220 Bloom g.
3. The method of claim 1, wherein the concentration of the type A gelatin in the solution I is 4-6 g/mL, and the concentration of the type B gelatin in the solution III is 4-6 g/mL.
4. The method of preparing an injectable dual drug delivery hydrogel of claim 1, wherein the volume ratio of solution I to absolute ethanol in solution II is 1:2 and the volume ratio of solution III to absolute ethanol in solution IV is 1:2.
5. The method for preparing the injectable dual drug delivery hydrogel according to claim 1, wherein the volume ratio of 25% glutaraldehyde, water and absolute ethanol in the solution five is 1:40-60:90-110.
6. The method for preparing the injectable dual-drug delivery hydrogel of claim 1, wherein the concentration of the EGCG solution is 10-25 mg/mL, and the feed liquid ratio of the A-type gelatin microspheres to the EGCG solution is 5-10 mg/mL.
7. The method for preparing the injectable dual drug delivery hydrogel of claim 1, wherein the SAG solution has a concentration of 0.4-1 mg/mL and the feed liquid ratio of the type B gelatin microspheres to the SAG solution is 1-5 mg/mL.
8. The method for preparing the injectable dual drug delivery hydrogel of claim 1, wherein the concentration of the matrix gelatin solution is 0.15-0.3 g/mL and the cross-linking agent is a zirconium chloride solution with a concentration of 0.025-0.2 g/mL.
9. The method for preparing the injectable dual drug delivery hydrogel of claim 1, wherein the feed liquid ratio of EGCG-loaded type A gelatin microspheres, SAG-loaded type B gelatin microspheres, matrix gelatin solution and cross-linking agent is 10-100 mg/10 mL/1 mL.
10. The injectable dual-drug delivery hydrogel prepared by the method for preparing an injectable dual-drug delivery hydrogel according to any one of claims 1 to 9.

Description

Injectable double-drug delivery hydrogel and preparation method thereof Technical Field The invention belongs to the technical field of biomedical materials, and particularly relates to an injectable double-drug delivery hydrogel and a preparation method thereof. Background Periodontitis is a common disease in which the host tissue microenvironment is deregulated and is the leading cause of tooth loss in adults. The pathological characteristics of the dental caries include deregulated immune response (expressed by immune cell infiltration and high secretion of proinflammatory cytokines), osteoclast formation and activation, and finally periodontal tissue destruction, so that bone defect repair of tooth sockets after tooth extraction faces challenges such as insufficient bone mass, continuous interference of inflammatory microenvironment and the like. Although the traditional periodontitis tooth socket treatment method (such as autologous bone grafting or heterogeneous bone replacement material) can partially maintain the bone profile, the traditional periodontitis tooth socket treatment method still has the limitations that the formation rate of new bone is low, the inflammation and the osteogenesis process cannot be synchronously regulated and controlled, and the like. In recent years, injectable hydrogels become research hotspots for alveolar ridge preservation due to their minimally invasive nature, good anatomical compliance and drug carrying capacity, however, achieving controlled drug release to synergistically balance anti-inflammatory and osteogenic effects remains a key challenge to be solved. Gelatin is widely used in tissue engineering as a collagen derivative due to its excellent biocompatibility and easy modification properties. However, conventional gelatin hydrogels often suffer from low mechanical strength and rapid degradation rates. The present study introduced zirconium ions (Zr 4+) as cross-linkers, which by forming stable coordination bonds with the carboxyl groups on the gelatin chain (presumably mainly octahedral geometry), constructed hydrogels (GZ) with good stability and injectability. The design not only mimics the characteristics of the natural bone extracellular matrix (ECM), but also provides an ideal carrier for constructing a drug delivery system. And a drug delivery system is better constructed by combining gelatin to form microspheres. Epigallocatechin gallate (EGCG) is the monomer with the strongest biological activity in green tea catechin, and has multiple biological effects of strong antioxidation, anti-inflammatory, antibacterial, anti-tumor, tissue repair promotion and the like. A great number of researches show that EGCG has remarkable effects in preventing and treating periodontitis, can effectively inhibit the growth of key periodontal pathogenic bacteria and the formation of biological membranes, lighten the direct damage of pathogens to tissues, and more importantly, can remarkably regulate overactive host immune inflammatory reaction, inhibit the expression of pro-inflammatory cytokines (such as TNF-alpha, iNOS and IL-6) and reduce inflammatory infiltration, and simultaneously, has the potential of inhibiting the activity of osteoclast, protecting gingival fibroblasts, reducing connective tissue damage and the like, and provides possibility for inhibiting alveolar bone absorption and promoting periodontal regeneration. Gli1 + cells are an important functional subset of periodontal ligament stem cells (PDLSCs), a key source of osteoblasts and cementum cells, normally involved in physiological remodeling of alveolar bone and cementum. However, in severe inflammatory microenvironments, gli1 + cells may be significantly inhibited in their osteogenic activity and may even exhibit pro-inflammatory behavior. Therefore, regulating Gli1 + cell activity is a strategy with great potential for repairing periodontitis bone defects. SAG (Smoothened Agonist) serving as a small molecule agonist of a Hedgehog (Hh) signal channel can specifically activate Smoothened (Smo) receptor, obviously up-regulate transcription and protein expression of Gli1 genes in Gli1 + cells, enhance differentiation capacity of the Gli1 genes to osteoblasts and cementum cells, and provide a new idea for periodontal bone regeneration. In the actual treatment process, the periodontitis bone defect has an irregular shape, and a minimally invasive and good anatomical compliance biological material is urgently needed for treatment. In addition, the periodontitis bone defect has the conditions of persistent inflammation, easy infection, bone absorption and the like, and the existing solution (single-function hydrogel and simple composite hydrogel) can only solve one or part of the problems, so that two aspects of inflammation and bone injury can not be well and synchronously coordinated. Therefore, for the difficult problem of unbalanced inflammatory microenvironment and bone regeneration process in periodon