聚电解质包覆的铕(Ⅲ)配合物@SiO_2荧光纳米粒的合成与性质

Preparation and Characterization of Polyelectrolyte Coated Fluorescent Silica Nanoparticles by Adsorbing Europium Chelate

以二苯甲酰甲烷(DBM)、邻菲罗琳(phen)和丙烯酸(AA)为配体,制备了铕的配合物Eu(Ⅲ)(DB M)_2-(phen)(AA)。利用St(o|¨)ber法合成了SiO_2纳米粒。通过超声辅助,将脂溶性的强荧光铕配合物吸附到SiO_2纳米粒上,再包覆阳离子聚电解质聚二烯丙基二甲基氯化铵(PDAC)和阴离子聚电解质聚丙烯酸(PAA),从而制备了Eu(Ⅲ)(DBM)_2(phen)(AA)@SiO_2/PDAC/PAA荧光纳米粒。采用透射电镜、紫外光谱、红外光谱、荧光光谱和Zeta电位等技术对荧光纳米粒进行了表征。作为一种新型的荧光纳米探针,该荧光纳米粒具有粒度均一且分布窄、荧光强度大、低泄漏和光稳定性好等优点,而表面包覆的PAA带有丰富的羧基,可直接与生物分子大量连接,可作为优良的时间分辨荧光标记物用于各种高灵敏生物检测中。

Uniform silica nanoparticles were synthesized via St（o｜¨）ber method,and fluorescent europium complex with three chelate ligands（i.e.dibenzoylmethane,phenanthroline and acrylic acid）has been prepared.The hydrosoluble silica nanoparticles adsorbed liposoluble europium chelate with strong fluorescence in the aid of ultrasonication and phase-transfer solvent,and then were coated by cationic polyelectrolyte polydi-allyldimethylammonium chloride and anionic polyelectrolyte poly（acrylic acid）（PAA）one layer by one layer. The obtained fluorescent nanoparticles were charactered by transmission electron microscopy,ultraviolet spectrophotometer, infrared spectrophotometer,fluorescence spectrophotometer and Zeta potential.These nanoparticles have the advantages of uniform size,strong fluorescence,good photostability and leakage free. Futhermore,the nanoparticles with rich carboxy groups resulting from PAA coated on their surfaces made the surface modification and bioconjugation easier.These properties suggest their great potential in the application field of biology and medicine.