PROBLEM TO BE SOLVED: To provide an adsorbing material having high blood group compatibility while suppressing deterioration of protein adsorbability.SOLUTION: The protein adsorbing material satisfies the following items (a)-(c). The item (a) is that a ratio of a nitrogen atom to all atoms on the surface of the protein adsorbing material is 0.1-8 (atomic number%) when measured by an X-ray electron spectroscopy (ESCA) method. The item (b) is that the amount of the β2-microglobulin to be adsorbed thereon is 0.05 μg/cm2 or larger. The item (c) is that the number of the blood platelets to be stuck to the surface thereof is 10 (pieces/4.3×103 μm2) or smaller.COPYRIGHT: (C)2015,JPO&INPIT【課題】本発明の課題は、タンパク質の吸着能の低下を抑制しつつ血液適合性の高い吸着材料を提供することにある。【解決手段】以下の項目を満たすことを特徴とするタンパク質吸着材料。（ａ）Ｘ線電子分光法（ＥＳＣＡ）により検出される、表面の全原子に対する窒素原子の割合が、０．１（原子数％）以上、８（原子数％）以下（ｂ）β２－マイクログロブリン吸着量０．０５μｇ／ｃｍ２以上（ｃ）表面の血小板付着数が１０（個／４．３×１０３μｍ２）以下【選択図】なし
