title: Controlled rupture of magnetic polyelectrolyte microcapsules for drug delivery.
abstract: In this study, a magnetic-sensitive microcapsule was prepared using Fe 3O 4/poly(allylamine) (Fe 3O 4/PAH) polyelectrolyte to construct the shell. Structural integrity, microstructural evolution, and corresponding release behaviors of fluorescence dyes and doxorubicin were systematically investigated. Experimental observations showed that the presence of the magnetic nanoparticles in the shell structure allowed the shell structure to evolve from nanocavity development to final rupture of the shell under a given magnetic stimulus of different time durations. Such a microstructural evolution of the magnetic sensitive shell structure explained a corresponding variation of the drug release profile, from relatively slow release to burst-like behavior at different stages of stimulus. It has proposed that the presence of magnetic nanoparticles produced heat, due to magnetic energy dissipation (as Brown and Neel relaxations), and mechanical vibration and motion that induced stress development in the thin shell. Both mechanisms significantly accelerated the relaxation of the shell structure, causing such a microstructural evolution. With such a controllable microstructural evolution of the magnetic-sensitive shell structure, active substances can be well-regulated in a manageable manner with a designable profile according to the time duration under magnetic field. A cell culture study also indicated that the magnetic-sensitive microcapsules allowed a rapid uptake by the A549 cell line, a cancerous cell line, suggesting that the magnetic-sensitive microcapsule with controllable rupturing behavior of the shell offers a potential and effective drug carrier for anticancer applications.
authors.affiliation: Department of Materials Sciences and Engineering, National Chiao Tung University, Hsinchu, Taiwan, 300, Republic of China.
authors.forename: Shang-Hsiu
authors.initials: SH
authors.lastname: Hu
authors.forename: Chia-Hui
authors.initials: CH
authors.lastname: Tsai
authors.forename: Chen-Fu
authors.initials: CF
authors.lastname: Liao
authors.forename: Dean-Mo
authors.initials: DM
authors.lastname: Liu
authors.forename: San-Yuan
authors.initials: SY
authors.lastname: Chen
mesh_terms: D000970:Antineoplastic Agents / Q000494:pharmacology; D002214:Capsules / Q000737:chemistry*; D045744:Cell Line, Tumor; D004337:Drug Carriers; D016503:Drug Delivery Systems; D004573:Electrolytes; D005290:Ferric Compounds / Q000737:chemistry; D006801:Humans; D008280:Magnetics; D053768:Metal Nanoparticles / Q000737:chemistry; D008855:Microscopy, Electron, Scanning; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry; D011073:Polyamines / Q000737:chemistry; D013997:Time Factors
chemical_list: D000970:Antineoplastic Agents; D002214:Capsules; D004337:Drug Carriers; D004573:Electrolytes; D005290:Ferric Compounds; D011073:Polyamines; C000499:ferric oxide; C063994:polyallylamine