酸化鉄ナノ粒子生物毒性のメカニズムとして,表面媒介によるヒドロキシルラジカルの生成
Maxim A Voinov1, Jason O Sosa Pagán, Erin Morrison
1Department of Chemistry, North Carolina State University, 2620 Yarbrough Drive, Raleigh, North Carolina 2769-8204, USA.
Journal of the American Chemical Society
|December 15, 2010
まとめ
酸化鉄ナノ粒子の表面は,フェントン反応を通じて反応性ヒドロキシルラジカルを生成します. ナノ粒子の表面によって媒介されるこの激素生成は,溶けたイオンより強力であり,表面の修正によって容易に抑制されません.
科学分野:
- ナノテクノロジー ナノテクノロジー
- マテリアルサイエンス 材料科学
- 環境科学 環境科学
背景:
- ナノサイズの鉄酸化物は,ナノテクノロジーでますます使用され,環境と健康上の懸念を提起しています.
- ナノマテリアルの誘発による根幹生成の理解は,潜在的生物毒性を評価する上で極めて重要です.
研究 の 目的:
- ガンマ-Fe(2) O(3) ナノ粒子によるヒドロキシルラジカル生成のメカニズムを調査する.
- ナノ粒子の表面と溶けた鉄イオンのラジカル生成効果を比較する.
- ラジカル生成を緩和する表面改変の効果を評価する.
主な方法:
- 電子パラマグネティック共振 (EPR) のスピントラップ実験.
- スーパーオキシード駆動フェントン反応条件.
- ナノ粒子と溶解したFe3+) イオンから発生するラジカルの比較分析.
- ナノ粒子の表面をオイル酸と牛の血清アルブミンで改造する.
主要な成果:
- ガンマ-Fe(2) O(3) ナノ粒子 (20-40 nm) は,フェントン反応を通じてヒドロキシル基 (OH(•)) の生成を媒介する.
- ラジカル生成は主に表面触媒反応によるもので,溶けたイオンによるものではありません.
- ナノ粒子の表面触媒センターは,溶解したFe3+) イオンよりも,少なくとも50倍も効率的にOHを生成します.
- 油酸塩またはBSAで表面の受動化は,OHの生産を抑制する上でほとんど効果的ではなかった.
結論:
- ガンマ-Fe(2) O(3) ナノ粒子の表面は,反応性のあるヒドロキシルラジカルの大量発生源である.
- 既存の表面改変戦略は,急性生成を防ぐには不十分である.
- 開発された実験プロトコルは,ナノ材料によるフリーラジカルの生成を評価し,生物毒性評価を支援することができます.
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