Nankai University, Tianjin 300071, P.R. China.
Chem Asian J. 2010 Jun 1;5(6):1332-40. doi: 10.1002/asia.200900463.
Magnetic silica-coated magnetite (Fe(3)O(4)) sub-microspheres with immobilized metal-affinity ligands are prepared for protein adsorption. First, magnetite sub-microspheres were synthesized by a hydrothermal method. Then silica was coated on the surface of Fe(3)O(4) particles using a sol-gel method to obtain magnetic silica sub-microspheres with core-shell morphology. Next, the trichloro(4-chloromethylphenyl) silane was immobilized on them, reacted with iminodiacetic acid (IDA), and charged with Cu(2+). The obtained magnetic silica sub-microspheres with immobilized Cu(2+) were applied for the absorption of bovine hemoglobin (BHb) and the removal of BHb from bovine blood. The size, morphology, and magnetic properties of the resulting magnetic micro(nano) spheres were investigated by using scanning microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and a vibrating sample magnetometer (VSM). The measurements showed that the magnetic sub-microspheres are spherical in shape, very uniform in size with a core-shell, and are almost superparamagnetic. The saturation magnetization of silica-coated magnetite (Fe(3)O(4)) sub-microspheres reached about 33 emu g(-1). Protein adsorption results showed that the sub-microspheres had a high adsorption capacity for BHb (418.6 mg g(-1)), low nonspecific adsorption, and good removal of BHb from bovine blood. This opens a novel route for future applications in removing abundant proteins in proteomic analysis.
磁性硅烷化磁铁矿 (Fe(3)O(4)) 亚微米球固定化金属亲和配体用于蛋白质吸附。首先，通过水热法合成磁铁矿亚微米球。然后，使用溶胶-凝胶法在 Fe(3)O(4) 颗粒表面涂覆硅烷，得到具有核壳结构的磁性硅烷化亚微米球。接下来，将三氯(4-氯甲基苯基)硅烷固定在其上，与亚氨基二乙酸 (IDA) 反应，并加载 Cu(2+)。所得固定化 Cu(2+) 的磁性硅烷化亚微米球用于吸附牛血红蛋白 (BHb) 和从牛血中去除 BHb。使用扫描显微镜 (SEM)、透射电子显微镜 (TEM)、X 射线衍射 (XRD) 和振动样品磁强计 (VSM) 研究了所得磁性微(纳)球的尺寸、形貌和磁性能。测量结果表明，磁性亚微米球呈球形，尺寸非常均匀，具有核壳结构，几乎具有超顺磁性。硅烷化磁铁矿 (Fe(3)O(4)) 亚微米球的饱和磁化强度约为 33 emu g(-1)。蛋白质吸附结果表明，亚微米球对 BHb 具有高吸附能力 (418.6 mg g(-1))，非特异性吸附低，从牛血中去除 BHb 效果好。这为未来在蛋白质组学分析中去除丰富蛋白质的应用开辟了新途径。
