Silk protein mainly consists of sericin protein and silk fibroin protein. Among them, the biological materials made of silk fibroin protein possess excellent biocompatibility, superior mechanical properties, controllable degradability, and no toxic by-products. They have demonstrated superior potential and broad clinical translation potential in the field of regenerative medicine, and have been applied in the research of tissue repair for soft tissue, skin, cornea, bone, tendon/ligament, etc. The regenerated silk fibroin protein derived from silkworms can be reprocessed, modified, and regulated to prepare various types of scaffold materials, which can then be used in numerous fields such as tissue engineering, drug delivery, 3D printing, cell coating, microfluidics, and biosensors.
The preparation process of regenerated silk fibroin mainly includes alkali gel removal, high-concentration salt dissolution, ultrafiltration desalination, and freeze-drying. The freeze-dried powder of regenerated silk fibroin can be used as a raw material for cosmetics, a medical auxiliary material, and can also be reshaped and then used to manufacture implantable medical devices.
An important step in the preparation process of regenerated silk fibroin is the removal of high concentrations of lithium bromide or calcium chloride. For instance, removing bromide ions from a concentration of up to 80% to a level of ≤ 80 mg/g, and lithium ions to be less than 2 mg/g.
The removal of lithium bromide is usually carried out using methods such as dialysis bags, organic hollow membranes, and electrodialysis. Due to the particularity of regenerated silk fibroin, the desalination by static standing of the dialysis bags can yield qualified products, but there are problems such as large water consumption and small processing capacity, making it impossible to scale up the process. The biggest problem with the desalination of silk fibroin products is that the desalted products are prone to gelation, turbidity, precipitation, etc., which seriously affects production.
In response to the challenges encountered during the desalination process of silk fibroin, Wuhan Bona has meticulously designed and strictly controlled the process, successfully developing multiple sets of highly efficient and stable ultrafiltration desalination technologies and dedicated equipment. These technologies and equipment not only successfully achieved the desalination goal, but also produced products that met the process and quality requirements. Currently, these mature ultrafiltration desalination technologies have been widely applied in several enterprises and have achieved remarkable results.
With its rich engineering experience and separation purification expertise, Wuhan Bona is adept at overcoming technical challenges. It not only provides customers with high-quality equipment solutions but also offers excellent process solutions to alleviate their concerns and jointly promote industrial development.
