Elucidation and technological development of methodologies that can ensure long-term aqueous dispersion stability of nanocrystal aqueous dispersion formulations

2021 Fiscal Year Final Research Report

• Project/Area Number: 18K04887
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 28030:Nanomaterials-related
• Research Institution: Osaka University
• Principal Investigator: Baba Koichi 大阪大学, 医学系研究科, 寄附講座教授 (00436172)
• Project Period (FY): 2018-04-01 – 2022-03-31
• Keywords: 薬剤ナノ結晶 / ステロイド / 眼内移行性向上 / 製剤の分散安定性

Outline of Final Research Achievements

Drug nanocrystal eye drops are expected to improve drug delivery into the eye due to their nano-order particle size effect. However, since drug nanocrystals easily aggregate in water, it is necessary to ensure the long-term aqueous dispersion stability of the particles from the viewpoint of formulation. The theme of this study was to elucidate the methodology and develop the technology to ensure the long-term aqueous dispersion stability of nanocrystal aqueous dispersion formulations. As a result, we developed a new method to prepare nanocrystal eye drops of fluorometholone, a steroidal ophthalmic drug, and found that by coating the surface of the nanocrystals with a compound called lanolin, the water dispersion stability of the drug nanocrystals can be maintained for about six months in refrigerated storage. This method is expected to be useful for research and development of aqueous dispersion formulations of nanocrystals in the future.

Free Research Field

ナノ結晶の作製と評価

Academic Significance and Societal Importance of the Research Achievements

一般に点眼液の眼への移行性は低いとされる。これは眼には様々なバリア機能が発達している為である。例えば、瞬きや涙液によって点眼後の薬剤は速やかに目の表面から洗い流され、鼻腔を通り体全体に拡散される。このため体全体への副作用が問題になることがある。点眼液を効率よく眼の中に移行させることが一つの課題であるが、我々は薬剤をナノメートルオーダーまで小さくしたナノ結晶点眼液の作製に成功し、点眼薬剤の眼内移行性が向上することを明らかにした。また比較的長期間、薬剤ナノ結晶の粒子分散性を確保できた。将来的にナノ結晶点眼液の開発が期待されるが、技術開発の際に役立つ基礎研究的な成果を挙げることに成功した。