近年來奈米科技蓬勃發展，金奈米材料優異生物相容性被受重視，根據結構 及粒徑大小而有更多元的應用性。金奈米棒依據入射光頻率產生表面電漿共振效應(SPR)吸收，其SPR吸收波段介於可見光與近紅外光間，廣泛應用於生醫、光電及顯影技術。
本研究金奈米棒 (gold nanorod，AuNR)被包覆於十六烷基三甲基溴化銨 (CTAB)，粒子表面帶正電分布於聚乙烯吡咯烷酮 (PVP)改質還原石墨烯 (reduce graphene oxide，RGO)得到的RGO-PVP上形成AuNR@RGO奈米複合物。AuNR@RGO具有光學穿透性並且能夠提升對於偵測物的接觸面積進而提高表面增強拉曼光譜 (surface-enhanced Raman scattering，SERS)偵測的靈敏度，藉由調控不同比例之AuNR和RGO尋找最佳拉曼增強效應並用於偵測染料小分子Rhodamine 6G (R6G) SERS訊號，也由於AuNR@RGO具有良好光熱效應，可置於雷射照射下產生熱能達到升溫作用。結果顯示AuNR@RGO不僅擁有良好之拉曼增強效應，在光熱升溫方面也有明顯的效果，為一多功能型奈米複合材料。

In recent years nanotechnology is flourishing. Gold (Au) based materials have excellent biocompatibility. By tuning the particle size and shape, a diverse range of applications are readily available. For a certain range of frequency of an incident light irradiated upon gold nanorod (AuNR), surface plasmon resonance (SPR) effect can be produced. The SPR effect was utilized to acquire the absorption bands between visible and near-infrared light (NIR) of the Au nanorod for biomedical, optical electronics, and imaging applications.
In this study, Au nanorods were prepared by seed-mediated growth method. Then Au nanorods were attached onto polyvinylpyrrolidone (PVP)-modified reduce graphene oxide (RGO) sheets through in situ self-assembly behaviors, termed as AuNR@RGO. The resulting AuNR@RGO was characterized systematically by transmission electron microscopy (TEM). It revealed that Au nanorods were immobilized and dispersed homogeneously on the surface of graphene oxide layer. The surface charge was confirmed by zetasizer measurement. The results showed that Au nanorods successfully immobilized on the graphene oxide. Furthermore, the rapid surface-enhanced Raman scattering (SERS) detection and identification of Rhodamine 6G (R6G) was conducted through Raman spectroscopy. In addition, photothermal effect was induced by external laser illumination. Hence, these new nanohybrids exhibit potentials for both sensing and thermal therapeutic applications.

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