金纳米棒表面等离子体共振瑞利散射能量转移光谱测定痕量硼

硼是一种生命体必需的微量元素，但过量的硼对人体以及动植物有害。建立一种高灵敏度，高选择性以及简便的硼检测方法，对于环境和人类健康都具有很重要的意义。本研究的目的是建立一种简便，灵敏，选择性测定硼的金纳米棒等离子体共振瑞利散射能量转移光谱新方法。直径为12 nm, 长度为37 nm的金纳米棒采用种子生长法制备。在pH 5.6的NH₄Ac-HAc的缓冲溶液中和甲亚胺-H存在下，金纳米棒在404 nm处产生较强的共振瑞利散射峰。当体系中存在硼酸时，硼酸与甲亚胺-H形成硼酸-甲亚胺-H配合物。作为散射受体的配合物与散射共振能量转移的给体纳金米棒靠近时，发生瑞利散射共振能量转移，导致瑞利散射信号猝灭。随着硼酸浓度的增加，形成的配合物增加，金纳米棒转移给黄色配合物的散射光能量增大，导致体系404 nm处的瑞利散射强度线性降低。其降低值ΔI_{404 nm}与硼的浓度在10～750 ng·mL-1范围内呈良好的线性关系。考察了共存物质对该法测定2.3×10-7 mol·L-1 B的干扰情况。结果表明该法具有较高的选择性，即4×10-4 mol·L-1的Mn2+，Cd2+，Zn2+，Bi3+，Na+，Al3+，葡萄糖，Hg2+，IO-₃，F-，SO2-₄，SiO2-₃，NO-₃，ClO-₄，过氧化氢等对硼的测定无干扰。据此建立了一个灵敏度高，选择性好，简便快速检测硼的瑞利散射共振能量转移新方法。

Determination of Trace Boron Based on Gold Nanorod Plasmonic Resonance Rayleigh Scattering Energy Transfer to the Coordinate

B is a necessary trace element for human and animals, but the excess intake of B caused poison. Thus, it is very important to determination of B in foods and water. The target of this study is development of a new, sensitive and selective resonance Rayleigh scattering energy transfer (RRS-ET) for the determination of B. The combination of energy transfer with resonance Rayleigh scattering (RRS) has developed a new technology called RRS-ET, which can realize selective and sensitive detection of boric acid. The gold nanorods in diameter of 12 nm and length of 37 nm were prepared by the seed growth procedure. In pH 5.6 NH₄Ac-HAc buffer solution and in the presence of azomethine-H (AMH), the gold nanorod particles exhibited a strong resonance Rayleigh scattering (RRS) peak at 404 nm. In the presence of boric acid, it reacts with AMH to form AMH-boric acid (AMH-B) complexes. When the complexe as a receptor close to the gold nanorod as a donor, the resonance Rayleigh scattering energy transfer (RRS-ET) take placed that resulted in the Rayleigh scattering signal quenching. With the increase of the concentration of boric acid, the formed complexes increased, the scattering light energy of gold nanorod transfer to the complexes increased, resulting in the Rayleigh scattering intensity linearly reduced at 404 nm. The decreased RRS intensity responds linearly to the concentration of boron over 10～750 ng·mL-1 B, with a regress equation of ΔI_{404 nm}=3.53ｃ+24 and a detection of 5 ng·mL-1 B. The influence of coexistence substances on the RRS-ET determination of 2.3×10-7 mol·L-1 B was considered in details. Results showed that this new RRS-ET method is of high selectivity, that is, 4×10-4 mol·L-1 Mn2+, Cd2+, Zn2+，Bi3+, Na+, Al3+, glucose, Hg2+, IO-₃, F-, SO2-₄, SiO2-₃, NO-₃, ClO-₄, H₂O₂, mannitol, glycerol, and ethylene glycol, 4×10-5 mol·L-1 L-tyrosine, and 2×10-4 mol·L-1 L-glutamic acid do not interfere with the determination. Based on this, a new sensitive, selective, simple and rapid RRS-ET method has been developed for the determination of trace boron in six mineral water samples that contain 24.9, 29.3, 57.9, 59.0, 84.9, and 105.1 ng·mL-1 B, with relative standard deviation of 1.6%～4.1% and recovery of 95.6%～109.6%.