Torchilin V P, Papisov M I, Smirnov V N
J Biomed Mater Res. 1985 Apr;19(4):461-6. doi: 10.1002/jbm.820190410.
Magnetic materials were suggested as carriers for protein immobilization about 10 years ago [1,2]. The main advantage of these carriers is their ability to be concentrated near magnetic terminals upon the application of the external magnetic field. This property is used in technological processes for selective catalyst removal from the reaction mixture [3], in immunological studies for the separation of cells to which magnetic particles are specifically bound modified with antibodies against cell surface components [4], in experiments for the drug targeting in vivo into appropriate tissues under the action of external magnetic field [5]. The properties of magnetic carriers are reviewed in [3]. There exist a number of methods to obtain porous magnetic carriers, containing immobilized matter not only on the surface, but also in the volume of a particle. Normally, these preparations are obtained by the granule formation from the suspension of ferromagnetic particles in the solution or melt of appropriate high-molecular-weight compound [5,6]. The drawback of the above-mentioned methods is the pronounced aggregation of ferromagnetic particles. The aggregation does not permit to use concentrated enough suspensions of magnetic particles and causes the formation of the product with a variety of sizes and magnetic properties. We made an attempt to synthesize the magnetic carrier for protein immobilization on the basis of commercial Sephadex porous spheres. Sephadex granules were made magnetic by adsorptional fixation of ferromagnetic particles in its pores. The properties of the "native" and "magnetic" Sephadexes as carriers for protein immobilization were compared by parallel immobilization on both carriers of alpha-chymotrypsin and 131I-albumin. In in vivo experiments we studied the ability of magnetic Sephadex to be concentrated in a desired region of the circulation under the action of external magnetic field.
大约10年前，人们提出将磁性材料用作蛋白质固定的载体[1,2]。这些载体的主要优点是，在施加外部磁场时，它们能够在磁终端附近聚集。这一特性被用于从反应混合物中选择性去除催化剂的工艺过程[3]、用于免疫研究中分离与磁性颗粒特异性结合的细胞，这些磁性颗粒用针对细胞表面成分的抗体进行了修饰[4]、用于在外部磁场作用下将体内药物靶向输送到合适组织的实验中[5]。[3]中对磁性载体的特性进行了综述。有多种方法可获得多孔磁性载体，其中不仅在颗粒表面，而且在颗粒内部都含有固定化物质。通常，这些制剂是通过从铁磁颗粒在适当的高分子化合物溶液或熔体中的悬浮液形成颗粒来制备的[5,6]。上述方法的缺点是铁磁颗粒明显聚集。聚集不允许使用浓度足够高的磁性颗粒悬浮液，并导致形成具有各种尺寸和磁性的产物。我们尝试以市售的葡聚糖多孔球为基础合成用于蛋白质固定的磁性载体。通过将铁磁颗粒吸附固定在葡聚糖颗粒的孔中，使葡聚糖颗粒具有磁性。通过在α-胰凝乳蛋白酶和131I-白蛋白的两种载体上平行固定，比较了“天然”和“磁性”葡聚糖作为蛋白质固定载体的特性。在体内实验中，我们研究了磁性葡聚糖在外部磁场作用下在循环系统中所需区域聚集的能力。
