Comparative Study of Coumarin-120 (C-120) and Stilbine-3 (STB-3) Laser Dyes Doped in Sol-Gel Glasses

In 1967 the first work in solid state dye laser was performed by doping rhodamine dyes in Polymethylmethacrylate (PMMA) materials. Since then some materials like various types of polymers, co-polymers, poly composite glasses have been used as host matrices for doping different laser dyes. Polymers suffer from limited mechanical and thermal stability. Hence glasses can be the alternative hosts. However, because of high processing temperature leading to permanent destruction of dye molecules, the conventional glass preparation technique is not suitable for the introduction of organic laser dyes. This difficulty can be overcome by introducing the laser dye molecules in sol-gel glass which is prepared at low temperature. Recent work with sol-gel glasses shows that these glasses may prove to be better materials compared to polymeric materials because glasses being hard, best optically transparency in Near UV-UV and Visible region and show better photostability. In this research work we reported, comparative study of the photophysical properties of Coumarin-120 (C-120) belonging to 7-aminocoumarin family having two hydrogen atoms attached to the N atom at the 7-position, with Stilbene-3 (STB-3) in three types of HCl catalyzed SiO2 sol-gel matrices prepared by Method I, Method II and Method III respectively.

二氧化硅-香豆素-3-羧酸抗菌杂化材料制备及抗菌活性

采用硅烷偶联剂3-氨丙基三乙氧基硅烷在酸性条件下对氯硅烷水解沉淀SiO_2表面进行改性,与具有抗菌等生物活性的香豆素-3-羧酸进行杂化,然后用抑菌圈法测其防霉性能。结果表明:抗菌杂化材料对青霉、黑曲霉、面孢霉、黑根霉都具有较强的防霉性能,且对黑曲霉的活性表现更好。