Universidade Estadual do Norte Fluminense Darcy Ribeiro - UENF, Av. Aberto Lamego 2000, Parque California, 28015-620 Campos dos Goytacazes, RJ, Brazil.
Universidade de São Paulo - USP, Av. Prof. Almeida Prado 1280, Butantâ, 05508-900 São Paulo, SP, Brazil.
Int J Biol Macromol. 2021 Jan 1;166:448-458. doi: 10.1016/j.ijbiomac.2020.10.203. Epub 2020 Oct 27.
Poly-3-hydroxybutyrate (P(3HB)) and poly-3-hydroxybutyrate-co-3-hydroxyhexanoate (P(3HB-co-3HHx)) are biocompatible and bioabsorbable biopolymers produced by different bacteria with potential for drug delivery in thermo-responsive magnetic microcarriers. Microparticles of P(3HB) and P(3HB-co-3HHx), with 5.85% mol of 3HHx, produced by Burkholderia sacchari, containing nanomagnetite (nM) and lipophilic hormone were prepared by simple emulsion (oil/water) technique leading to progesterone (Pg) encapsulation efficiency higher than 70% and magnetite loads of 3.1 and 2.3% (w/w) for P(3HB)/nM/Pg and P(3HB-co-3HHx)/nM/Pg, respectively. These formulations were characterized by Infrared spectroscopy, X-ray diffraction, Thermal gravimetric analysis and Electron microscopy (TEM, SEM) techniques. The P(3HB)/nM/Pg and P(3HB-co-3HHx)/nM/Pg microparticles presented spherical geometry with wrinkled surfaces and average size between 2 and 40 μm for 90% of the microparticles. The release profiles of the P(3HB)/nM/Pg and P(3HB-co-3HHx)/nM/Pg formulations showed a hormone release trigger (6.9 and 11.1%, respectively) effect induced by oscillating external magnetic field (0.2 T), after 72 h. Progesterone release in non-magnetic tests with P(3HB-co-3HHx)/nM/Pg revealed a slight increment (5.6%) in relation to P(3HB)/nM/Pg. The experimental release of the P(3HB)/nM/Pg and P(3HB-co-3HHx)/nM/Pg samples presented a good agreement with Higuchi model. The 3HHx comonomer content improves the hormone release of the P(3HB-co-3HHx)/nM/Pg formulation with potential for application to synchronize the estrous cycle.
聚 3-羟基丁酸酯（P(3HB)）和聚 3-羟基丁酸酯-共-3-羟基己酸酯（P(3HB-co-3HHx)）是由不同细菌产生的具有生物相容性和可生物降解性的生物聚合物，具有在热响应磁性微载体中药物输送的潜力。由 Burkholderia sacchari 产生的 5.85%mol 3HHx 的 P(3HB)和 P(3HB-co-3HHx)微球，含有纳米磁铁矿（nM）和亲脂性激素，通过简单的乳液（油/水）技术制备，导致孕酮（Pg）包封效率高于 70%，磁铁矿负载分别为 3.1%和 2.3%（w/w），用于 P(3HB)/nM/Pg 和 P(3HB-co-3HHx)/nM/Pg。这些制剂通过红外光谱、X 射线衍射、热重分析和电子显微镜（TEM、SEM）技术进行了表征。P(3HB)/nM/Pg 和 P(3HB-co-3HHx)/nM/Pg 微球呈现出球形几何形状，表面有皱纹，90%的微球平均粒径在 2 至 40 μm 之间。P(3HB)/nM/Pg 和 P(3HB-co-3HHx)/nM/Pg 制剂的释放曲线显示，在磁场（0.2 T）振荡后，激素释放触发（分别为 6.9%和 11.1%）。在没有磁场的 P(3HB-co-3HHx)/nM/Pg 测试中，与 P(3HB)/nM/Pg 相比，孕酮释放略有增加（5.6%）。P(3HB)/nM/Pg 和 P(3HB-co-3HHx)/nM/Pg 样品的实验释放与 Higuchi 模型吻合较好。3HHx 共聚单体含量提高了 P(3HB-co-3HHx)/nM/Pg 制剂中激素的释放，具有同步发情周期的应用潜力。
