Preparation process of high molecular weight silk fibroin freeze-dried powder

Abstract

The invention discloses a preparation process of high molecular weight silk fibroin freeze-dried powder. The silk fibroin freeze-dried powder can be rapidly and completely dissolved in water, and is applicable to various fields of biomedicine clinic. The preparation process, from controlling an interaction between molecules of the silk fibroin, changes pH value, ionic strength and concentration of a silk fibroin solution, and implements high pressure and high temperature sterilization to induce transformation of the silk fibroin from complex protein structures such as single molecule, polymer and nanoparticle to stable nanoparticle which is about 50-300nm, so as to inhibit interaction as well as coagulation and cross-linking between the molecules of the silk fibroin; therefore, the freeze-dried powder can be prepared through a basic freeze-drying procedure. The silk fibroin, which has been sterilized at high temperature before being freeze-dried, can be directly applied to clinic treatment without further disinfection treatment, thus greatly simplifying operation steps and saving cost.

Description

technical field [0001] The invention relates to the field of biological materials, in particular to a preparation process of large molecular weight silk fibroin freeze-dried powder. Background technique [0002] In recent years, starting from the regenerated silk fibroin solution, a variety of degradable biomaterials such as thin films, particles, porous scaffolds and hydrogels after further processing have been proved to have excellent biocompatibility and non-immunogenicity. It degrades slowly and is becoming a new type of medical biomaterial. It can be directly used as a product for tissue repair in the clinic, and can also be used as a drug and cell carrier scaffold for drug sustained release and tissue engineering to build artificial organs. Therefore, silk fibroin solution is the basis for preparing all silk fibroin-based biomaterials. How to purify silk fibroin solution with high quality, high molecular weight and high stability is the key to further develop silk fibr...

AI Technical Summary

Problems solved by technology

This has brought great inconvenience to the downstream material preparation and application, mainly reflected in: (1) waste of time and materials, every time the material is prepared, the silk fibroin solution needs to be re-purified; (2) product quality is difficult to control, repeated poor sex

Even if the large molecular weight regenerated silk fibroin solution is stored in a 4°C refrigerator, the structure of the silk fibroin is slowly changing, and the molecules are constantly aggregating, which may directly affect the performance of the prepared materials below; (3) It is difficult to store and transport, and the Regenerated silk fibroin solution is sold directly as a commodity, or sold as the main component of injectable gels, etc., all need to consider the storage temperature and conditions, which is also the primary problem restricting its large-scale application development

In addition, the regenerated silk fibroin solution required for the preparation and application of certain materials has a high concentration, and the purified silk fibroin solution can only be obtained by further concentration methods, such as polyethylene glycol dialysis, ultrafiltration, etc. Concentration silk fibroin solution, bringing additional cost and contamination risk to material preparation