National Engineering Laboratory for Fiber Optic Sensing Technology, Wuhan University of Technology, Wuhan 430070, PR China; Key Laboratory of Fiber Optic Sensing Technology and Information Processing (Wuhan University of Technology), Ministry of Education, Wuhan 430070, PR China.
National Engineering Laboratory for Fiber Optic Sensing Technology, Wuhan University of Technology, Wuhan 430070, PR China; Key Laboratory of Fiber Optic Sensing Technology and Information Processing (Wuhan University of Technology), Ministry of Education, Wuhan 430070, PR China.
Mater Sci Eng C Mater Biol Appl. 2014 Feb 1;35:29-35. doi: 10.1016/j.msec.2013.10.012. Epub 2013 Nov 1.
A novel nitric oxide (NO) fluorescent probe CdS-poly(methyl methacrylate) (PMMA) nanocomposites with different molar ratios of CdS quantum dots (QDs) to PMMA are developed successfully via in-situ bulk polymerization method. The optical properties of CdS/PMMA nanocomposites are studied by UV-Vis absorption spectra and fluorescence (FL) spectra in detail. It is demonstrated that the optical properties from such nanocomposite solution are tuned and stabilized by simply varying the concentration of CdS in the final product. X-ray diffraction (XRD) patterns of CdS-PMMA nanocomposite with higher loading of CdS show broad pattern for cubic CdS, which has narrow particle size distribution with less than 5 nm in PMMA observed by transmission electron microscopy (TEM). The surface morphological characterization of the CdS-PMMA nanocomposite has been done through atomic force microscopy (AFM). The thermo-gravimetric analyses (TGA) and differential scanning calorimetry (DSC) confirm the enhanced thermal stability of CdS-PMMA nanocomposites than PMMA. NO can coordinate with Cd(2+) as a ligand for transition metal complexes, which will cause a quenching effect on the fluorescence of CdS QDs. Therefore, a significant quenching effect on the fluorescence of the CdS-PMMA nanocomposite is observed in the presence of NO. The fluorescence responses are concentration-dependent and can be well described by the typical Stern-Volmer equation, and a linear calibration I0/I=1.0021+0.1944[NO] (R(2)=0.96052) is obtained in the range from 1.4×10(-5) to 9.3×10(-3) mol/L NO with a detection limit of 1.0×10(-6) mol/L (S/N=3).
一种新型的一氧化氮（NO）荧光探针 CdS-聚甲基丙烯酸甲酯（PMMA）纳米复合材料，通过原位本体聚合方法成功制备，CdS 量子点（QD）与 PMMA 的摩尔比不同。详细研究了 CdS/PMMA 纳米复合材料的光学性质，通过紫外-可见吸收光谱和荧光（FL）光谱。结果表明，通过简单改变最终产物中 CdS 的浓度，可以调节和稳定纳米复合材料溶液的光学性质。具有较高 CdS 负载量的 CdS-PMMA 纳米复合材料的 X 射线衍射（XRD）图谱显示出立方 CdS 的宽图案，通过透射电子显微镜（TEM）观察到 PMMA 中 CdS 的粒径分布较窄，小于 5nm。通过原子力显微镜（AFM）对 CdS-PMMA 纳米复合材料进行了表面形貌表征。热重分析（TGA）和差示扫描量热法（DSC）证实 CdS-PMMA 纳米复合材料的热稳定性比 PMMA 增强。NO 可以作为配位体与 Cd(2+)配位，从而对 CdS QD 的荧光产生猝灭效应。因此，在存在 NO 的情况下，CdS-PMMA 纳米复合材料的荧光发生了显著的猝灭效应。荧光响应与浓度有关，可以很好地用典型的 Stern-Volmer 方程描述，在 1.4×10(-5)到 9.3×10(-3) mol/L 的 NO 范围内，得到了 I0/I=1.0021+0.1944[NO]（R(2)=0.96052）的线性校准曲线，检测限为 1.0×10(-6) mol/L（S/N=3）。
