Hongfei Liu, Jie Zhu, Pengyue Bao, Yueping Ding, Jiapeng Wang, Yi Du, Yang Qu and Ying Xu* Pages 1 - 12 ( 12 )
Background: Protein drugs have disadvantages, such as short half-lives, unstable biological activities, and low utilization efficiency.
Objective: In this paper, a porous ion-responsive targeted drug delivery system was designed, combining biodegradable carriers with ion exchange technology to overcome problems for protein drug delivery systems.
Method: Carboxymethyl chitosan porous microspheres (CCPM) were prepared using an emulsification-chemical crosslinking method. Chitosan-bovine serum albumin-carboxymethyl chitosan porous microspheres (CBCCPM) were prepared using a dynamic ion exchange method and static self-assembly technology.
Results: CCPM were round in appearance mostly with a particle size distribution of 5-15 μm, which facilitates passive targeting to the lungs. CCPM had a total ion exchange capacity of 9.97 ± 0.07 mmol/g and showed a strong ability to attract and contain positively charged drugs. A potentiometric titration curve was used to identify the dissociation behavior of exchangeable groups on the microspheres; the optimal pH for ion exchange of microspheres was ≥ 4.3. CCPM had ion responsiveness, in vitro degradation ability, thermal stability and biocompatibility. In vitro release results confirmed that BSA and CCPM were mainly bound together by ionic bonds and the drug release mechanism of the self-assembled microspheres changed from particle diffusion to membrane diffusion under pH 7.4 PBS solution containing 0.02% Tween 80. Circular dichroism and sodium dodecyl-sulfate polyacrylamide gel electrophoresis results showed no significant change in the secondary structure and purity of BSA after binding to CCPM. The cumulative in vitro release rate of microspheres after 24 hours was 86.78%.
Conclusion: In this paper, CBCCPM, a porous ion-responsive targeted drug delivery system, was designed.
carboxymethyl chitosan porous microspheres (CCPM), targeted drug delivery system, ion exchange, in vitro evaluation, protein drugs, self-assembly technology
Jiangsu University,Wuyi University, College of pharmacy,School of Biotechnology and Health Sciences, Jiangsu University, College of pharmacy, Chia Tai Tianqing Pharmaceutical Group Co., LTD, Formulation development, Jiangsu Sihuan Biopharmaceutical Co., Ltd, Formulation development, Jiangsu University, College of pharmacy, Wuyi University, School of Biotechnology and Health Sciences, Jiangsu University,Chia Tai Qingjiang Pharmaceutical Industry Co., Ltd, College of pharmacy,Formulation development, Jiangsu University, College of pharmacy, Jiangsu University, Xuefu Road 301, Zhenjiang, 212013