title: Preparation and properties of BSA-loaded microspheres based on multi-(amino acid) copolymer for protein delivery.
abstract: A multi-(amino acid) copolymer (MAC) based on ω-aminocaproic acid, γ-aminobutyric acid, L-alanine, L-lysine, L-glutamate, and hydroxyproline was synthetized, and MAC microspheres encapsulating bovine serum albumin (BSA) were prepared by a double-emulsion solvent extraction method. The experimental results show that various preparation parameters including surfactant ratio of Tween 80 to Span 80, surfactant concentration, benzyl alcohol in the external water phase, and polymer concentration had obvious effects on the particle size, morphology, and encapsulation efficiency of the BSA-loaded microspheres. The sizes of BSA-loaded microspheres ranged from 60.2 μm to 79.7 μm, showing different degrees of porous structure. The encapsulation efficiency of BSA-loaded microspheres also ranged from 38.8% to 50.8%. BSA release from microspheres showed the classic biphasic profile, which was governed by diffusion and polymer erosion. The initial burst release of BSA from microspheres at the first week followed by constant slow release for the next 7 weeks were observed. BSA-loaded microspheres could degrade gradually in phosphate buffered saline buffer with pH value maintained at around 7.1 during 8 weeks incubation, suggesting that microsphere degradation did not cause a dramatic pH drop in phosphate buffered saline buffer because no acidic degradation products were released from the microspheres. Therefore, the MAC microspheres might have great potential as carriers for protein delivery.
authors.affiliation: College of Physical Science and Technology, Sichuan University, Chengdu, Shanghai, People's Republic of China.
authors.forename: Xingtao
authors.initials: X
authors.lastname: Chen
authors.affiliation: College of Physical Science and Technology, Sichuan University, Chengdu, Shanghai, People's Republic of China.
authors.forename: Guoyu
authors.initials: G
authors.lastname: Lv
authors.affiliation: Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, People's Republic of China.
authors.forename: Jue
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, People's Republic of China.
authors.forename: Songchao
authors.initials: S
authors.lastname: Tang
authors.affiliation: College of Physical Science and Technology, Sichuan University, Chengdu, Shanghai, People's Republic of China.
authors.forename: Yonggang
authors.initials: Y
authors.lastname: Yan
authors.affiliation: Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, People's Republic of China.
authors.forename: Zhaoying
authors.initials: Z
authors.lastname: Wu
authors.affiliation: Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, People's Republic of China.
authors.forename: Jiacan
authors.initials: J
authors.lastname: Su
authors.affiliation: Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai, People's Republic of China.
authors.forename: Jie
authors.initials: J
authors.lastname: Wei
mesh_terms: D000596:Amino Acids / Q000737:chemistry*; D002214:Capsules / Q000138:chemical synthesis*; D003692:Delayed-Action Preparations / Q000008:administration & dosage / Q000737:chemistry*; D004058:Diffusion; D008422:Materials Testing; D010316:Particle Size; D012710:Serum Albumin, Bovine / Q000008:administration & dosage / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D000596:Amino Acids; D002214:Capsules; D003692:Delayed-Action Preparations; D012710:Serum Albumin, Bovine
keywords: degradation; poly (amino acid) copolymer; release