Kim Do-Kyun, Park Tae Jung, Tamiya Eiichi, Lee Sang Yup
BioProcess Engineering Research Center, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon 305-701, Korea.
J Nanosci Nanotechnol. 2011 May;11(5):4188-93. doi: 10.1166/jnn.2011.3680.
In the recent research, the development of optical biosensing devices has been focused on finding new method and technologies to exploit the optical properties of noble metal nanostructure, especially localized surface plasmon resonance (LSPR). In this study, we fabricated a LSPR-based label-free optical biosensor with the multi-spot gold-capped nanoparticle array (MG-NPA) biochip based on the deposition of a thin gold (Au) film on the silica nanoparticles layer with the simple process. The MG-NPA biochip used the silica nanoparticles as the core and a thin Au film as a shell on the surface. This structure can excite the LSPR signal easily with the high reproducibility. The anti-leptin antibody was immobilized on the surface of MG-NPA biochip, which could recognize only leptin antigen. The leptin antibody-antigen interaction was performed by the introduction of different concentration (1 pg/mL-100 microg/mL) of leptin antigen solutions for 1 h. The detection limit was found to be 100 pg/mL by using the anti-leptin antibody immobilized MG-NPA biochip. This LSPR-based label-free optical biosensor employing the MG-NPA biochip brings several advantages such as low cost, easy to fabricate, using a simple optical system and can be applied in a wide immunoassay with the similar antibody-antigen model.
在最近的研究中，光学生物传感设备的发展一直聚焦于寻找新的方法和技术来利用贵金属纳米结构的光学特性，尤其是局域表面等离子体共振（LSPR）。在本研究中，我们通过简单的工艺，在二氧化硅纳米颗粒层上沉积一层薄金（Au）膜，制备了基于多斑点金帽纳米颗粒阵列（MG-NPA）生物芯片的无标记LSPR光学生物传感器。MG-NPA生物芯片以二氧化硅纳米颗粒为核心，表面有一层薄金膜作为外壳。这种结构能够以高重现性轻松激发LSPR信号。抗瘦素抗体固定在MG-NPA生物芯片表面，它只能识别瘦素抗原。通过引入不同浓度（1 pg/mL - 100 μg/mL）的瘦素抗原溶液1小时来进行瘦素抗体-抗原相互作用。使用固定有抗瘦素抗体的MG-NPA生物芯片，检测限为100 pg/mL。这种采用MG-NPA生物芯片的基于LSPR的无标记光学生物传感器具有成本低、易于制备、使用简单光学系统等优点，并且可以应用于具有类似抗体-抗原模型的广泛免疫分析中。
