以Au/Cu纳米棒为基底的肺腺癌组织的特征表面增强拉曼光谱研究

Special Surface Enhanced Raman Scattering on Lung Cancer Tissues Based on Au/Cu Nanorods Substrate

通过金铜共混法制备了Au/Cu合金纳米棒,研究了铜掺杂对金纳米棒等离子体共振吸收和结构的影响,探究了Au/Cu合金纳米棒的等离子体共振拉曼增强效应.以Au/Cu合金纳米棒为基底对肺腺癌组织和癌旁正常组织进行了表面增强拉曼光谱检测.结果显示,癌变组织具有比癌旁正常组织更强的拉曼信号峰,位于1250,1344,1408,1568,1608和2560 cm^(-1)附近的拉曼峰分别与蛋白质的AmideⅡ氨基化合物、C—H弯曲振动、核酸中CH_3的对称变角振动、蛋白质色氨酸惰性环振动、蛋白质酰胺I谱带分子间反平行β-折叠的C—O健伸缩振动和蛋白质的巯基(S—H)伸缩振动有关,2936 cm^(-1)附近的拉曼峰为蛋白质CH_2的对称伸缩振动和CH_3的反对称伸缩振动共同作用产生.以铜掺杂的金纳米棒为基底的表面增强拉曼光谱法有望成为检测肺癌组织的有效手段.

Au/Cu nanorods were prepared by mixing method. The influence of doping copper ions on the plasmon resonance absorption and morphology of gold nanorods was investigated. The plasmon resonance Raman enhancement effect on Au/Cu alloy nanorods was detected. The Raman molecular vibration information of lung cancer tissues and corresponding non-tumor normal tissues were compared on Au/Cu alloy nanorods substrate.Surface enhanced Raman scattering（ SERS） analysis of lung cancer tissues and corresponding non-tumor normal tissues demonstrate that the Raman peaks of cancer tissues are stronger compared to non-tumor normal tissues because the SERS signals of protein molecules in lung adenocarcinoma are influenced by their spatial conformation and molecular symmetry. The results suggest that tissue carcinogenesis increases the symmetry of the molecular structure and the Raman peaks near 1250,1344,1408,1568,1608 and 2560 cm^（-1）are relevant to amino-compounds of amide Ⅱ in protein,C—H bending vibration,symmetrical variable angle vibration of CH_3 in nucleic acids,inert ring vibration of tryptophan in protein and C—O stretching vibration of amide Ⅰband in protein with intermolecular antiparallel β-fold and sulfhydryl（ S—H） stretching vibration of proteins,respectively. The Raman peak near 2936 cm^（-1）is generated by the joint action of the symmetric stretching vibration of CH_2 and the antisymmetric stretching vibration of CH_3 in protein. Herein,SERS based on Au/Cu alloy nanorods as substrate is promising to be an effective method for the detection of lung cancer.