Dudás Zoltán, Fagadar-Cosma Eugenia, Len Adél, Románszki Loránd, Almásy László, Vlad-Oros Beatrice, Dascălu Daniela, Krajnc Andraž, Kriechbaum Manfred, Kuncser Andrei
Wigner Research Centre for Physics, Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P.O. 49, 1525 Budapest, Hungary.
Institute of Chemistry Timisoara of Romanian Academy, Laboratory of Inorganic Chemistry, Bv. Mihai Viteazul, No. 24, RO-300223 Timișoara, Romania.
Materials (Basel). 2018 Apr 6;11(4):565. doi: 10.3390/ma11040565.
This work is focused on a novel class of hybrid materials exhibiting enhanced optical properties and high surface areas that combine the morphology offered by the vinyl substituted silica host, and the excellent absorption and emission properties of 5,10,15,20-tetrakis(-methyl-4-pyridyl)porphyrin-Zn(II) tetrachloride as a water soluble guest molecule. In order to optimize the synthesis procedure and the performance of the immobilized porphyrin, silica precursor mixtures of different compositions were used. To achieve the requirements regarding the hydrophobicity and the porous structure of the gels for the successful incorporation of porphyrin, the content of vinyltriacetoxysilane was systematically changed and thoroughly investigated. Substitution of the silica gels with organic groups is a viable way to provide new properties to the support. An exhaustive characterization of the synthesized silica samples was realised by complementary physicochemical methods, such as infrared spectroscopy (FT-IR), absorption spectroscopy (UV-Vis) and photoluminescence, nuclear magnetic resonance spectroscopy (Si-MAS-NMR) transmission and scanning electron microscopy (TEM and SEM), nitrogen absorption (BET), contact angle (CA), small angle X ray and neutron scattering (SAXS and SANS). All hybrids showed an increase in emission intensity in the wide region from 575 to 725 nm (Q bands) in comparison with bare porphyrin. By simply tuning the vinyltriacetoxysilane content, the hydrophilic/hydrophobic profile of the hybrid materials was changed, while maintaining a high surface area. Good control of hydrophobicity is important to enhance properties such as dispersion, stability behaviour, and resistance to water, in order to achieve highly dispersible systems in water for biomedical applications.
这项工作聚焦于一类新型杂化材料，这类材料展现出增强的光学性能和高比表面积，它结合了乙烯基取代硅石主体所提供的形态结构，以及作为水溶性客体分子的5,10,15,20-四（-甲基-4-吡啶基）卟啉-锌（II）四氯化物的优异吸收和发射性能。为了优化合成过程以及固定化卟啉的性能，使用了不同组成的硅石前驱体混合物。为了满足成功掺入卟啉所需的凝胶疏水性和多孔结构要求，系统地改变并深入研究了乙烯基三乙酰氧基硅烷的含量。用有机基团取代硅胶是赋予载体新性能的可行方法。通过互补的物理化学方法，如红外光谱（FT-IR）、吸收光谱（UV-Vis）和光致发光、核磁共振光谱（Si-MAS-NMR）、透射和扫描电子显微镜（TEM和SEM）、氮吸附（BET）、接触角（CA）、小角X射线和中子散射（SAXS和SANS），对合成的硅石样品进行了详尽表征。与裸卟啉相比，所有杂化材料在575至725nm的宽区域（Q带）发射强度均有所增加。通过简单调节乙烯基三乙酰氧基硅烷含量，杂化材料的亲水/疏水特性得以改变，同时保持高比表面积。良好的疏水性控制对于增强诸如分散性、稳定性行为和耐水性等性能很重要，以便在生物医学应用中实现水中的高度可分散体系。
