Medina-Ramírez A, Flores-Díaz A A, Ruiz Camacho B, García-Ruiz G
Division de Ciencias Naturales y Exactas, Chemical Engineering Department, Universidad de Guanajuato, Campus Guanajuato. Noria Alta s/n, 36050, Guanajuato, Guanajuato, Mexico.
Nanotechnology Engineering, Universidad de La Ciénega del Estado de Michoacan de Ocampo, Av. Universidad #3000 Lomas de la Universidad, 56020, Sahuayo, Michoacan, Mexico.
Prog Biomater. 2018 Mar;7(1):61-71. doi: 10.1007/s40204-018-0085-2. Epub 2018 Feb 10.
The synthesis of calcium silicate supported zeolite membrane was carried out by second growth method. The chemical nature of the functionalizing agent on the formation of homogenous zeolite membrane was evaluated. One monomer and two cationic polymers were used: 3-aminopropyltriethoxysilane (APS), polyethylenimine (PEI) and polydiallyldimethylammonium chloride (PDDA). The support was subjected to chemical functionalization and then it was rubbed with zeolite crystals. The W zeolite was used as zeolite seed in two different Si/Al ratios. The functionalized and rubbed supports were submitted to hydrothermal treatment at 150 °C for 48 h. The bioactivity of the homogeneous zeolite membranes was evaluated by the biomimetic method through the membranes soaking in a simulated body fluid (SBF) at 37 °C for 21 days. Two immersion methods were evaluated. The products were characterized by XRD and SEM techniques. The results indicated that the supported functionalization with PDDA and the Si/Al ratio (higher than 1.8) of zeolite enhanced the interaction between the support and the zeolite precursor enhancing the formation of homogeneous zeolite membrane on the surface. The presence of the functional groups of PDDA on the membrane was detected by FTIR. After immersion in SBF, the zeolite membrane was stable and led to the formation of Ca-P layer on its surface. The re-immersion method led to the formation of richer Ca/P layer (1.36). These findings allowed generating a zeolite membrane with combined properties of calcium silicate and the controllable porosity of zeolitic material making it potentially useful for bone regeneration and drug releasing.
采用二次生长法合成了硅酸钙负载的沸石膜。评估了功能化剂的化学性质对均匀沸石膜形成的影响。使用了一种单体和两种阳离子聚合物：3-氨丙基三乙氧基硅烷（APS）、聚乙烯亚胺（PEI）和聚二烯丙基二甲基氯化铵（PDDA）。对载体进行化学功能化处理，然后用沸石晶体进行摩擦。以两种不同硅铝比的W沸石作为沸石晶种。将功能化并摩擦后的载体在150℃下进行48小时的水热处理。通过将均匀沸石膜在37℃的模拟体液（SBF）中浸泡21天的仿生方法评估其生物活性。评估了两种浸泡方法。通过XRD和SEM技术对产物进行表征。结果表明，用PDDA进行负载功能化以及沸石的硅铝比（高于1.8）增强了载体与沸石前驱体之间的相互作用，促进了表面均匀沸石膜的形成。通过FTIR检测到膜上存在PDDA的官能团。在SBF中浸泡后，沸石膜稳定，并在其表面形成了钙磷层。再浸泡法导致形成更富的钙/磷层（1.36）。这些发现使得能够制备出具有硅酸钙综合性能和可控孔隙率的沸石膜，使其在骨再生和药物释放方面具有潜在应用价值。
