【摘要】：介孔材料自發(fā)現(xiàn)以來(lái)，憑借自身的一些優(yōu)異的特征，例如大的比表面積、可調(diào)變的介孔孔徑、表面可通過(guò)各種修飾實(shí)現(xiàn)“官能化”等，在催化、分離、藥物與生物活性分子的負(fù)載等許多領(lǐng)域有廣泛的應(yīng)用前景。隨著納米制備技術(shù)的發(fā)展，介孔納米顆粒在基因載體和藥物載體方面，發(fā)現(xiàn)越來(lái)愈多的應(yīng)用前景。介孔二氧化硅納米顆粒作為理想基因和藥物載體，對(duì)其顆粒的尺寸、形貌、分散性等的參數(shù)的要求便至關(guān)重要。因此，探討球狀單分散的介孔二氧化硅MCM-41納米顆粒的合成的方法便具有理論與現(xiàn)實(shí)的意義。 本文使用了兩種方法制備了球狀單分散介孔二氧化硅MCM-41納米顆粒，并探討了合成因素的影響。一是添加劑法，即在尿素合成體系中，加入合適的添加劑，利用其某些特定作用包括抑制、分散、封裝等去改善介孔二氧化硅納米顆粒的質(zhì)量、大小以及均一性等；二是緩沖劑法，利用Tris-HCl緩沖溶液消除pH值不穩(wěn)定帶來(lái)的納米顆粒不均相增長(zhǎng)，制備出單分散形貌均一的二氧化硅納米顆粒。然后，改變溫度和體系的pH值合成一系列的介孔二氧化硅納米顆粒。 在添加劑法中，通過(guò)SEM、TEM、XRD、熱重分析等測(cè)試手段表明：添加劑的加入使尿素的使用量的大大降低，，從9.300g降低到了3.096g；在乙醇胺、酒石酸和丙三醇的幫助下，合成的介孔二氧化硅納米顆粒具有較好的XRD衍射峰，高的單分散性和大小均一的球形形貌，顆粒的尺寸可以被調(diào)制在75nm到200nm。與沒(méi)有添加劑相比，在顆粒的形貌與單分散性保證的前提下，顆粒尺寸下降了一個(gè)數(shù)量級(jí)。 在Tris-HCl緩沖體系中，能夠得到非常完美的介孔二氧化硅納米顆粒。結(jié)果表明：當(dāng)體系反應(yīng)溫度為60℃，pH值在7.8～8.2范圍內(nèi)，反應(yīng)時(shí)間為16h，為合成理想的、單分散、球形均一的介孔的材料的最佳反應(yīng)條件。此外，通過(guò)改變溫度以及合成pH值，可以制備出尺寸在80～300nm可調(diào)，分散性高的、形貌均一的、有序的介孔MCM-41納米顆粒，為其應(yīng)用成為理想的基因載體和藥物載體做了良好的鋪墊。
[Abstract]:Since its discovery, mesoporous materials have been catalyzed and separated by their own excellent characteristics, such as large specific surface area, adjustable mesoporous pore size, and "functionalization" of the surface through various modifications. Many fields, such as drug and bioactive molecule loading, have a wide application prospect. With the development of nanometer preparation technology, more and more applications of mesoporous nanoparticles have been found in gene carriers and drug carriers. As an ideal gene and drug carrier, mesoporous silica nanoparticles are very important for their particle size, morphology and dispersity. Therefore, it is of theoretical and practical significance to study the synthesis of spherical monodisperse mesoporous silica MCM-41 nanoparticles. In this paper, the spherical monodisperse mesoporous silica MCM-41 nanoparticles were prepared by two methods, and the effects of synthesis factors were discussed. One is additive method, that is, adding suitable additive in urea synthesis system, using some specific functions, such as inhibition, dispersion, encapsulation and so on, to improve the quality, size and uniformity of mesoporous silica nanoparticles. Secondly, the Tris-HCl buffer solution was used to eliminate the uneven phase growth of nano-particles caused by the instability of pH value, and the monodisperse silica nanoparticles were prepared. Then, a series of mesoporous silica nanoparticles were synthesized by changing the temperature and pH value of the system. In the additive method, the addition of the additive reduced the usage of urea from 9.300 g to 3.096 g, with the help of ethanolamine, tartaric acid and glycerol. The synthesized mesoporous silica nanoparticles have good XRD diffraction peak, high monodispersity and uniform spherical morphology. The size of the particles can be modulated from 75nm to 200nm. Compared with no additives, the particle size decreased by one order of magnitude under the guarantee of the morphology and monodispersity of the particles. Perfect mesoporous silica nanoparticles can be obtained in Tris-HCl buffer system. The results show that when the reaction temperature is 60 鈩

本文編號(hào)：2185476