【公開日：2024.07.25】【最終更新日：2024.06.29】
課題データ / Project Data
課題番号 / Project Issue Number
23UT0309
利用課題名 / Title
Effective design of PEGylated polyion complex (PIC) nanoparticles for enhancing PIC internalisation in cells utilising block copolymer combinations with mismatched ionic chain lengths
利用した実施機関 / Support Institute
東京大学 / Tokyo Univ.
機関外・機関内の利用 / External or Internal Use
内部利用（ARIM事業参画者以外）/Internal Use (by non ARIM members)
技術領域 / Technology Area
【横断技術領域 / Cross-Technology Area】（主 / Main）計測・分析/Advanced Characterization（副 / Sub）-
【重要技術領域 / Important Technology Area】（主 / Main）次世代ナノスケールマテリアル/Next-generation nanoscale materials（副 / Sub）-
キーワード / Keywords
Polyion complexes,電子顕微鏡/ Electronic microscope,ナノ粒子/ Nanoparticles
利用者と利用形態 / User and Support Type
利用者名（課題申請者）/ User Name (Project Applicant)
Fadlina Aulia
所属名 / Affiliation
東京大学 大学院工学系研究科
共同利用者氏名 / Names of Collaborators in Other Institutes Than Hub and Spoke Institutes
ARIM実施機関支援担当者 / Names of Collaborators in The Hub and Spoke Institutes
木村 鮎美
利用形態 / Support Type
（主 / Main）技術補助/Technical Assistance（副 / Sub）-
利用した主な設備 / Equipment Used in This Project
報告書データ / Report
概要（目的・用途・実施内容）/ Abstract (Aim, Use Applications and Contents)
This research demonstrated that fine-tuning the physicochemical properties of polyion complexes (PICs) is a promising solution for overcoming the PEG dilemma. Nanoparticles fabricated via electrostatic interaction between the anionic and cationic residues from PEGylated polypeptides as building blocks. Several physicochemical parameters of PICs, including polypeptide length, ionic residue crosslinking and chemical modification, and PEG length and morphology. Several morphologies could be prepared by adjusting PEG ratio of complexes. One of the morphologies possesses hollow nano capsule structure termed as Vesicle PIC. To confirm the general morphologies, basically transmission electron microscope (TEM) with Gd staining was utilized. Atomic Force Microscope (AFM) could also be used for morphology confirmation. However, for vesicle, to confirm the hollow membrane structure, cryoTEM was necessary to obtain high quality picture, particularly to verify formation unilamellar membrane.
実験 / Experimental
Cryo-TEM observation was performed to verify the inner hollow structure of the Vesicle PIC. The ultrapure water solution of the PIC (56, 100) with a crosslinking degree of 50% was dropped onto a Quantifoil grid (a copper grid coated with a thin film of R2/1 holey carbon, purchased from EM Japan, Tokyo, Japan). The Quantifoil grid containing the sample solution was blotted onto a paper to remove excess sample solution on a Leica EM GP plunge freezer (Leica Microsystems, Wetzlar, Germany). The sample solution was immediately vitrified by rapid immersion in liquid ethane (−175 °C). The frozen specimen was transferred to a JEM-2100F instrument (JEOL, Tokyo, Japan) using a cryo-transfer holder (Gatan 914, Gatan, Pleasanton, CA, USA) at liquid nitrogen temperature throughout the measurement. The microscope was equipped with a field emission gun (ZrO/W(100)) and a 4k × 4k CCD camera (UltraScan, Gatan, Pleasanton, CA, USA).
結果と考察 / Results and Discussion
To prepare Vesicle PIC, combinations between carboxyl groups from Poly(α,β-aspartic acid) (PAsp) as an anion source and amine groups from Poly-L-lysine (PLL) as a cation source were selected. PEG block with molecular weight 2000 was introduced at the terminal of anionic building block. The polymerization degree was designed to be between 60 and 100 repeating units. In current result, vesicle morphology was fabricated by combining PEG-PAsp(56) and homoPLL (100) in ionic charge mol ratio 1:1. Final PEG fraction value was 10%. Crosslinking treatment was performed at 50% of ionic residues to preserve the structure. As a result, Vesicle PIC can be obtained with size around 150 nm, confirmed by dynamic light scattering. By cryoTEM observation, formation of hollow membrane structure was observed, with the thickness of unilamellar membrane to be 12.0 ± 2.5 nm.
図・表・数式 / Figures, Tables and Equations
cryo-TEM images of Vesicle PIC (56,100; 50%-crosslinking) (Scale bar: 200 nm). Thickness of membrane was measured to be 11.98 ± 2.5 nm.
その他・特記事項（参考文献・謝辞等） / Remarks(References and Acknowledgements)
成果発表・成果利用 / Publication and Patents
論文・プロシーディング（DOIのあるもの） / DOI (Publication and Proceedings)
-
Fadlina Aulia, Effective design of PEGylated polyion complex (PIC) nanoparticles for enhancing PIC internalisation in cells utilising block copolymer combinations with mismatched ionic chain lengths, Journal of Materials Chemistry B, 12, 1826-1836(2024).
DOI: 10.1039/D3TB02049E
口頭発表、ポスター発表および、その他の論文 / Oral Presentations etc.
特許 / Patents
特許出願件数 / Number of Patent Applications：0件
特許登録件数 / Number of Registered Patents：0件