To investigate the preparation conditions of the oligochitosan-alginate microcapsules and analyze the membrane thickness, mechanical strength and permeability so as to make a microcapsule with the best performance.METHODS:
The microcapsule was prepared by changing the pH value of the oligochitosan solution and reaction time. Inverted phase contrast microscope was used to observe and calculate the membrane thickness. Mechanical strength of microcapsule was determined with a shaker and a pressure testing machine. Membrane permeability was estimated with bovine serum albumin (BSA) release profiles.RESULTS:
Membrane thickness of the microcapsule was increased with the increase of the reaction time when the pH value of the oligochitosan solution reached 7. Under this condition, the compress modulus of the microcapsule had reached 5.12 Kpa after 10 minutes and none of them damaged after shaking for 6 hours. Protein release rate of the microcapsule decreased with the increase of reaction time. When reaction for 10 minutes, protein release rate decreased with the increase of the concentration of salt ions; however, protein release rate increased with the increase of the concentration of salt ions after 20 minutes.CONCLUSION:
The microcapsules prepared under the pH value 7 exhibited good mechanical properties. The membrane permeability, under short reaction time, was mainly affected by membrane thickness. However, the membrane permeability was mainly affected by membrane density when reaction time was prolonged.