Encapsulation efficiency and dissolution of bromelain from chitosan-poly(N-vinylpyrrolidone) semi-IPN hydrogel

Bromelain is one of protease enzyme used in many medical fields, such as inflammation systemic oral, anticoagulant, therapeutic effect like antithrombotic and fibrinolytic. However, a controlled enzyme formula is required so that enzyme can sustain in the stomach for a period of time so that it will increase its absorption in the intestine. In this research, a chitosan-PNVP semi-IPN hydrogel is made to encapsulate bromelain as a carrier to release bromelain in the intestine without losing its activity. Hydrogel was synthesized using semi-IPN method with formaldehyde as a crosslinking agent. Furthermore, a bromelain solution was encapsulated into hydrogel matrix with post loading method. Artificial gastric and intestine fluid was used to evaluate the dissolution of bromelain. The encapsulation efficiency of bromelain was 97%, respectively. Dissolution occurred at pH 7.4 for 10 hours and pH 1.2 for 2 hours and pH 7.4 up to 12 hours each gives value equal to 57.4% and 99.9%. Enzyme activity assay conducted to the bromelain released shows the activity can be maintained up to 0.366 U/mL until it reaches artificial intestine environment.