Ag@SiO2/ZnO@SiO2的制备及其对水溶液中生物分子的分析检测  

Preparation of Ag@SiO_2/ZnO@SiO_2 and Its Application in Detection of Biological Molecules in Aqueous Solution

作　　者：黄文艺[1] 魏慧丹 史智鹏 白大伟[1] 马蓝宇 李利军[1] 

机构地区：[1]广西科技大学生物与化学工程学院,广西糖资源绿色加工重点实验室,广西高校糖资源加工重点实验室,广西柳州545006

出　　处：《分析测试学报》2015年第8期905-910,共6页Journal of Instrumental Analysis

基　　金：国家自然科学基金(31060219);广西自然科学基金(2014GXNSFAA118402);广西科技大学博士启动基金项目(12Z04)

摘　　要：采用一种操作简单、反应条件温和的方法在室温下制备了ZnO@SiO2和Ag@SiO2/ZnO@SiO2,利用透射电子显微镜（TEM）、紫外吸收光谱（UV）、荧光光谱（FL）、纳米粒度和ZETA电位分析仪等技术对所制备纳米粒子的粒径大小、吸收光谱、发光性质进行表征。结果表明,ZnO@SiO2核壳量子点的平均粒径为3-8 nm,最大紫外吸收波长在330 nm左右,可发射510 nm的黄绿色荧光。而Ag@SiO2增强了ZnO@SiO2核壳量子点的荧光,未改变ZnO@SiO2核壳量子点的发射峰位置,同时Ag@SiO2显著增强了ZnO@SiO2核壳量子点的荧光稳定性。利用L-半胱氨酸和血红蛋白对量子点荧光不同程度的猝灭作用,建立了一种简单、快速、灵敏的检测分析方法。在最佳条件下,L-半胱氨酸和血红蛋白的浓度分别在0.068-10.10 mg/L和4.00×10^2-4.00×10^3mg/L范围内与溶液的荧光强度呈良好的线性关系,相关系数（r^2）分别为0.993 8和0.9951,以3.37 mg/L的L-半胱氨酸标准溶液进行11次平行实验,相对标准偏差（RSD）为1.3%,以3倍标准偏差计算检出限为6.92×10^-3mg/L。以2.00×10^3mg/L的血红蛋白标准溶液进行11次平行实验,相对标准偏差为2.5%,以3倍标准偏差计算检出限为2.04 mg/L。A simple, rapid and mild condition method was developed for the preparation of ZnO@SiO2 core-shell structures quantum dots and Ag@SiO2/ZnO@SiO2 nanocomposite. Particle sizes, UV- vis absorption and emission spectra were characterized by transmission electron microscopy （TEM）, ultraviolet spectrometry （ UV ）, fluorescence spectroscopy （ FL ）, nanometer particle size analyzer and ZETA potentials techniques. The results showed that the particles sizes of ZnO@SiO2 core - shell structures quantum dots were 3 - 8 nm and could emit yellow green fluorescence under the excitation of UV - vis light. Their maximum absorption wavelength was 330 nm, and the maximum fluorescence emission wavelengths were located at 510 nm. Ag@SiO2/ZnO@SiO2 could enhance the fluorescent of ZnO@SiO2 core - shell quantum dot, but it didn＇t change the emission peak position of ZnO@SiO2 core - shell quantum dot. Otherwise, Ag@SiO2/ZnO@SiO2 greatly enhanced the fluorescent stability of ZnO@SiO2 core - shell quantum dots at room temperature. Based on different level quenching of hemoglobin and L - cysteine for quantum dots, a simple, rapid and sensitive detection method was established. Under the optimized conditions, the characteristic fluorescence intensity of Ag@SiO2/ZnO@SiO2 at 510 nm was linearly proportional to the concentration of L-cysteine and hemoglobin in ranges of 0. 068 - 10. 10 mg/L and 4. 00 ×10^2 - 4. 00 × 10^3 mg/L, respectively. The detection limits were 6. 92 × 10^-3 mg/L and 2. 04 mg/L, respectively, and the correlation coefficients were 0. 993 8 and 0. 995 1, respectively. The relative standard deviations for 11 replicate detections of 3.37 mg/L L-cysteine and 2. 00 × 10^3 mg/L hemoglobin were 1.3% and 2. 5% , respectively.

关 键 词：氧化锌 纳米银 荧光 稳定性 分析检测 血红蛋白 L-半胱氨酸 

分 类 号：O657.3[理学—分析化学] O629.7[理学—化学]