作为人体体液之一的尿液中含有多种人体新陈代谢的产物以及体内排出的毒素, 如果能够对这些组分进行定性分析, 就能够在一定程度上有效反映人体器官的健康状况, 这是临床医学中重要的研究途径。 该实验分别以785和1 030 nm激光作为源激发, 以具有电磁场增强的金纳米粒子作为基底, 利用表面增强拉曼散射光谱(SERS)对临床实验研究中所用的人体新鲜尿液的成份进行快速、 无损分析。 通过控制金纳米溶胶与尿液原液的混合比例从而来制备一系列具有不同配比的实验样品, 并且通过实验我们获得其相应的SERS光谱。 由实验结果分析可知, 我们能够有效地得到尿液中尿酸、 次黄嘌呤等多种成份的SERS光谱。 与此同时, 我们还研究了在不同波长激光条件下的尿液的SERS光谱。 相较于1 030 nm的激光, 785 nm的激光得到的SERS光谱具有较高的分辨率以及较低的背景值。 与此同时, 利用具有1 030 nm激光的便携式拉曼仪对实验样品进行快速、 无损分析, 有望为临床医学现场、 快速分析诊断提供帮助和支持。 而且相信, SERS能够在人类健康甚至生物组织的检测等方面提供更加详细的信息。

In this work, we have mainly studied SERS spectra of fresh human urine by using Au nanoparticles excited by 785 and 1 030 nm lasers, respectively. And the UV/Vis adsorption experiment of the Au nanoparticles mixed with different ratio of urine has been performed, and the obvious shifting of corresponding absorption band is observed. The result showed that the Au nanoparticles which have been synthesized by classical Fren’s method can interact with urine, and the Au nanoparticles aggregations caused by the urine have strong SERS effect. Intense and repeatable spectra of the urine samples can be quickly obtained using Au colloids, which characterized by the scanning electron microscope (SEM) and the high-resolution transmission electron microscope (HRTEM) images, and it can be confirmed that the size of the Au nanoparticles is about 55 nm with a finite variation. When different spectra can be detected under different exciting lasers, the various biofluid to Au substrate ratios can generate different intense spectra. From the spectra of 785 nm laser, we can conclude that it has lower background and higher resolution with more detail information of this system contained human urine. For the 1 030 nm laser, a portable Raman instrument is helpful for on-site clinic treatment detection. It also gets well defined information and will be a good and convenient choice for urine analysis. It should note that this peak band located at 1 006 cm-1 may be the dominant nitrogen-containing component in urine. On the other hand, uric acid, urea, hypoxanthine as well as creatinine can be assigned; the other bands are still unknown, which might be attributed to biomarkers important for disease differentiation. Another result shows that different sample preparation can influence the SERS spectra with different ratio. We also have made a comparison of Raman spectra between 785 and 1 030 nm lasers to learn the difference between each other just like background and high-resolution. The current study indicates the SERS of urine might be a good choice and tool for urinalysis with potential diagnostic application, especially with the portable Raman instrument which would be an accurate and convenient approach for urine analysis. It is possible for SERS detection to be applied in not only the health diagnosis but also biological tissue in the future.