PROBLEM TO BE SOLVED: To provide a super-paramagnetic iron-oxide nano-particle having a positive charge, a contrast medium using this and a manufacturing method thereof.SOLUTION: A super-paramagnetic iron-oxide nano-particle having a positive charge according to the present invention comprises: a super-paramagnetic iron-oxide nano-particle a high polymer layer including a high polymer containing many carboxyl groups with which a surface of the nano-particle is coated and a positive ionicity substance connected with a surface of the high polymer layer by an amide bond. According to the present invention, the super-paramagnetic iron-oxide nano-particle can be produced easily and with sufficient repeatability so as to have a hydrophilic property and strong positive ionicity. The produced super-paramagnetic iron-oxide nano-particle having the positive charge has high intracellular absorption efficiency and stability, and can be utilized variously as an effective contrast medium using a non-invasive organism image.COPYRIGHT: (C)2012,JPO&INPIT【課題】正電荷性の超常磁性酸化鉄ナノ粒子と、これを利用した造影剤及びその製造方法を提供する。【解決手段】本発明による正電荷性の超常磁性酸化鉄ナノ粒子は、超常磁性酸化鉄ナノ粒子と、前記ナノ粒子の表面にコーティングされた多数のカルボキシル基を含有する高分子を含む高分子層と、前記高分子層の表面にアミド結合で連結された陽イオン性物質とを含む。本発明によれば、超常磁性酸化鉄ナノ粒子を親水性且つ強い陽イオン性を有するように、簡単に且つ再現性良く製造することができる。製造された正電荷性の超常磁性酸化鉄ナノ粒子は、高い細胞内吸収効率及び安定性を有し、非侵襲的生体画像を用いた効果的な造影剤として多様に活用されることができる。【選択図】図1
