| 内容提要: |
Firstly, the amphiphilic block copolymer mPEG-Azo-PAsp-IM (200 mg) was dissolved in 20 mL methanol, and photosensitizer Chlorin e6(Ce6) (20 mg) was dissolved in 5 mL methanol. The solution of Ce6 was added dropwise to the solution of polymer with constantly stirring and the ratio of polymer to Ce6 is 10:1 (w/w) in the mixture solution, and then the mixture solution was dried at 45oC using a rotary evaporator to remove methanol.
Secondly, PBS solution (pH 7.4, 0.18 M) was added to the dried film and stirred for 1 h in dark at room temperature.
Thirdly, the excess Ce6 was eliminated by the following 2 steps: centrifugation (7,000 g × 15 min) to discard the undissolved Ce6, and then with ultrafiltration membrane (MWCO=3,000 Da, 2000 g×20 min) to get rid of the free Ce6 in PBS solution. The concentrated solution was collected and lyophilized. |