摘要
在一种含柠檬酸盐的溶液中,柠檬酸根阴离子自组装于带正电荷的金纳米微粒表面,使金纳米微粒成为一种被柠檬酸根包裹的带负电荷的超分子化合物.在pH4.4-6.8的弱酸性介质中,它可与质子化的卡那霉素(KANA)阳离子借静电引力、疏水作用力结合,形成粒径更大的聚集体(平均粒径从12增至20nm),这种聚集体的形成在引起金纳米的等离子体吸收带明显红移(△λ=102nm)的同时,共振瑞利散射(RRS)显著增强并且倍频散射(FDS)和二级散射(SOS)等共振非线性散射也有较大的增强,最大散射峰分别位于280nm(RRS),310nm(FDS)和480nm(SOS)处.在适当条件下,散射强度(△I)与卡那霉素的浓度成正比,其中RRS法灵敏度最高,因此金纳米微粒可作为测定卡那霉素的高灵敏RRS探针,它对卡那霉素的检出限为10.52ng·mL-1,方法有较好的选择性,可用于血液中卡那霉素的测定,文中还讨论了有关反应机理和RRS增强的原因.
In a citrate containing solution, anion of citrate self-assembled on Au nanoparticle surface with positive charge, making Au nanoparticle become a supermolecular compound with negative charge surrounded by citrate. In a weak acid medium of pH 4.4-6.8, the supermolecular compound can combine with kanamycin by the virtue of electrostatic and hydrophobic interaction, forming aggregate with bigger diameters (average diameter increased from 12 to 20 nm). The aggregate made plasmon absorption band of glod nanoparticle show evident bathochromic effect (Delta gimel = 102 nm), resonance Rayleigh scattering (RRS) intensity be enhanced greatly and the resonance nonlinear scattering such as frequency double scattering (FDS) and second order scattering (SOS) be increased markedly as well. The maximum scattering peaks are at 280 nm for RRS, 310 nm for FDS and 480 nm for SOS respectively. In optimum conditions, there was a linear relationship between scattering intensity Delta I and the concentration of kanamycin, and the highest sensitivity was RRS. So gold nanoparticle could be the RRS probe of high sensitivity for kanamycin with the detection limits of kanamycin being 10.52 ng.mL(-1). The method has good selectivity and has been successfully applied to the detection of kanamycin in clinic serum samples. In addition, the reaction mechanism and the reasons for the enhancement of RRS were discussed.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2005年第11期997-1002,i002,共7页
Acta Chimica Sinica
基金
国家自然科学基金(No.20175018)重庆市科委基金(No.20038113)资助项目.
