PDF(Pubmed)
Abstract：
OBJECTIVE: This study was designed to test the feasibility of using thin-film freezing (TFF) to prepare aerosolizable dry powders of plasmid DNA (pDNA) for pulmonary delivery.
METHODS: Dry powders of pDNA formulated with mannitol/leucine (70/30, w/w) with various drug loadings, solid contents, and solvents were prepared using TFF, their aerosol properties (i.e., mass median aerodynamic diameter (MMAD) and fine particle fraction (FPF)) were determined, and selected powders were used for further characterization.
RESULTS: Of the nine dry powders prepared, their MMAD values were about 1-2 µm, with FPF values (delivered) of 40-80%. The aerosol properties of the powders were inversely correlated with the pDNA loading and the solid content in the pDNA solution before TFF. Powders prepared with Tris-EDTA buffer or cosolvents (i.e., 1,4-dioxane or tert-butanol in water), instead of water, showed slightly reduced aerosol properties. Ultimately, powders prepared with pDNA loading at 5% (w/w), 0.25% of solid content, with or without Tris-EDTA were selected for further characterization due to their overall good aerosol performance. The pDNA powders exhibited a porous matrix structure, with a moisture content of < 2% (w/w). Agarose gel electrophoresis confirmed the chemical integrity of the pDNA after it was subjected to TFF and after the TFF powder was actuated. A cell transfection study confirmed that the activity of the pDNA did not change after it was subjected to TFF.
CONCLUSIONS: It is feasible to use TFF to produce aerosolizable pDNA dry powder for pulmonary delivery, while preserving the integrity and activity of the pDNA.
METHODS: Dry powders of pDNA formulated with mannitol/leucine (70/30, w/w) with various drug loadings, solid contents, and solvents were prepared using TFF, their aerosol properties (i.e., mass median aerodynamic diameter (MMAD) and fine particle fraction (FPF)) were determined, and selected powders were used for further characterization.
RESULTS: Of the nine dry powders prepared, their MMAD values were about 1-2 µm, with FPF values (delivered) of 40-80%. The aerosol properties of the powders were inversely correlated with the pDNA loading and the solid content in the pDNA solution before TFF. Powders prepared with Tris-EDTA buffer or cosolvents (i.e., 1,4-dioxane or tert-butanol in water), instead of water, showed slightly reduced aerosol properties. Ultimately, powders prepared with pDNA loading at 5% (w/w), 0.25% of solid content, with or without Tris-EDTA were selected for further characterization due to their overall good aerosol performance. The pDNA powders exhibited a porous matrix structure, with a moisture content of < 2% (w/w). Agarose gel electrophoresis confirmed the chemical integrity of the pDNA after it was subjected to TFF and after the TFF powder was actuated. A cell transfection study confirmed that the activity of the pDNA did not change after it was subjected to TFF.
CONCLUSIONS: It is feasible to use TFF to produce aerosolizable pDNA dry powder for pulmonary delivery, while preserving the integrity and activity of the pDNA.
摘要：
目的：本研究旨在测试使用薄膜冷冻（TFF）制备用于肺部递送的质粒DNA（pDNA）的可雾化干粉的可行性。
方法：用甘露醇/亮氨酸（70/30，w/w）配制的pDNA干粉，固体含量，使用TFF制备溶剂，它们的气溶胶特性(即，确定质量中值空气动力学直径（MMAD）和细颗粒分数（FPF）），和选择的粉末用于进一步表征。
结果：在制备的九种干粉中，它们的MMAD值约为1-2μm，FPF值（交付）为40-80%。粉末的气溶胶性质与TFF之前pDNA负载和pDNA溶液中的固体含量成反比。用Tris-EDTA缓冲液或共溶剂制备的粉末(即，1,4-二恶烷或叔丁醇在水中），而不是水，显示气溶胶性质略有降低。最终,用5%(w/w)的pDNA负载制备的粉末，0.25%的固体含量，选择有或没有Tris-EDTA用于进一步表征,因为它们的总体良好的气溶胶性能。pDNA粉末表现出多孔基质结构，水分含量<2%(w/w)。琼脂糖凝胶电泳证实pDNA在进行TFF后和TFF粉末活化后的化学完整性。细胞转染研究证实pDNA的活性在进行TFF后没有变化。
结论：使用TFF生产可雾化的pDNA干粉用于肺部给药是可行的，同时保持pDNA的完整性和活性。
方法：用甘露醇/亮氨酸（70/30，w/w）配制的pDNA干粉，固体含量，使用TFF制备溶剂，它们的气溶胶特性(即，确定质量中值空气动力学直径（MMAD）和细颗粒分数（FPF）），和选择的粉末用于进一步表征。
结果：在制备的九种干粉中，它们的MMAD值约为1-2μm，FPF值（交付）为40-80%。粉末的气溶胶性质与TFF之前pDNA负载和pDNA溶液中的固体含量成反比。用Tris-EDTA缓冲液或共溶剂制备的粉末(即，1,4-二恶烷或叔丁醇在水中），而不是水，显示气溶胶性质略有降低。最终,用5%(w/w)的pDNA负载制备的粉末，0.25%的固体含量，选择有或没有Tris-EDTA用于进一步表征,因为它们的总体良好的气溶胶性能。pDNA粉末表现出多孔基质结构，水分含量<2%(w/w)。琼脂糖凝胶电泳证实pDNA在进行TFF后和TFF粉末活化后的化学完整性。细胞转染研究证实pDNA的活性在进行TFF后没有变化。
结论：使用TFF生产可雾化的pDNA干粉用于肺部给药是可行的，同时保持pDNA的完整性和活性。
