纳米金颗粒是近年研究最为广泛的纳米材料之一，它具有良好的生物相容性、化学稳定性以及独特的光学性质，在生物分子检测、诊断和治疗方面具有很大的发展潜力。尤其是纳米金显示出特殊的表面等离子体共振现象，导致了粒子表面产生强电磁场，并最终增强了诸如吸收和散射的辐射特性，其散射光强与粒子的尺寸和团聚状态有密切关系。而由于共振现象而产生的纳米金对光的强烈吸收并高效转换为热效应也被用于检测和治疗。此外，与纳米金尺寸相关的局域表面等离子体共振光学特性，能够在粒子附近产生很强的电磁场增强，从而构成表面增强拉曼散射的基础。纳米金在强光照射下也表现出良好的抗光漂白的荧光现象，其特有的荧光寿命也成为检测的一种有效手段。与其他荧光物质作用时，又表现出表面增强荧光特性以及荧光共振能量转移。综述中，在介绍纳米金这些特殊光学性质的基础上，回顾了其在生物分子检测方面的应用进展。

Gold nanoparticles are one of the most widely studied nanoscale materials in recent years. It has great potential applications in area of bimolecular detection, diagnosis and therapy, due to their unique optical properties, facile surface chemistry, excellent biocompability and chemical stability. Especially, gold nanoparticles exhibit a unique phenomenon:strong surface plasmon resonance that lead to strong electromagnetic fields on the particle surface and consequently enhances all the radiative properties such as absorption and scattering. The scattering light intensity is extremely sensitive to the size and aggregation state of the particles, and the efficient conversion from light into heat by these gold nanoparticles can also be used for detection and therapy. Additionally, the main parameter of size-dependant optical properties of gold nanoparticles is the localized surface plasmon resonance (LSPR) known to generate a strong local enhancement of the electromagnetic field at the vicinity of the nanoparticles, this phenomenon is the basis of the surface enhanced Raman scattering. Furthermore, gold nanoparticles show excellent behavior of anti-photobleaching under the presence of strong light illumination, its fluorescence lifetime imaging can be used to detect such as cancer cells using molecularly targeted gold nanoparticles. Gold nanoparticle-based enhancement fluorescence emission and fluorescience resonance energy transfer were also discussed. In this review, we cover these important optical properties of gold nanoparticels and address their recent application on bioprobe.