Silica Gel Functionalized with Polyethylenimine as Advanced Sorbents for the Removal of Endotoxin from Gelatin

Gelatin is one of the essential materials for tissue engineering for its unique physicochemical properties. The endotoxin in gelatin needs to be controlled at a reasonable level to guarantee biosafety when applied to the human body. However, the isothermal titration calorimetry results showed specific interactions between gelatin and endotoxin, suggesting the difficulties of removing endotoxin from gelatin in mild conditions. In this work, a polyethyleneimine-grafted silica gel adsorbent for endotoxin was designed and prepared. Results showed that the prepared endotoxin adsorbent could remove endotoxin from gelatin without significantly changing the structures and properties of gelatin.