Abstract：Uniform size chitosan microspheres were prepared by a novel T-shaped microchannel. The effects of emulsifier, different flow rate ratios and flow rates on the preparation of chitosan microspheres were studied, respectively. In addition, chitosan droplets with different molecular weights were prepared using the T-shaped microchannel device, and the effects of different glutaraldehyde solutions on cross-linking of microspheres were studied. The preparation conditions of chitosan microspheres were determined as follows: the diameter of oil phase channel in the T-shaped microchannel was 350 mm, the diameter of water phase channel was 65 mm, and the joint diameter of two channel was 16 μm. 1.5%(w) chitosan was dissolved in aqueous acetic acid, which was used as a water phase. A mixture of liquid paraffin and petroleum ether 7:5(j) containing 4%(w) PO-500 emulsifier was used as an oil phase, the flow rate of water phase was 20 mL/min, and the flow rate ratio of oil to water phase was 15:1. The results show that the coefficient of variation (CV value) of all the chitosan droplets was below 10%. Glutaraldehyde toluene solution was finally chosen as the cross-linking agent of microspheres, the molar ratio of aldehyde group of glutaraldehyde to amino group of chitosan at 1:1 and the cross-linking time of glutaraldehyde 2 h.
2008, Vol. 8 
