Abstract:
In a specific biosensing application, a nanoplasmonic sensor chip has been tested by an experimental setup based on an aluminum holder and two plastic optical fibers used to illuminate and collect the transmitted light. The studied plasmonic probe is based on gold nanograting, realized on the top of a Poly(methyl methacrylate) (PMMA) chip. The PMMA substrate could be considered as a transparent substrate and, in such a way, it has been already used in previous work. Alternatively, here it is regarded as a slab waveguide. In particular, we have deposited upon the slab surface, covered with a nanograting, a synthetic receptor specific for bovine serum albumin (BSA), to test the proposed biosensing approach. Exploiting this different experimental configuration, we have determined how the orientation of the nanostripes forming the grating pattern, with respect to the direction of the input light (longitudinal or orthogonal), influences the biosensing performances. For example, the best limit of detection (LOD) in the BSA detection that has been obtained is equal to 23 pM. Specifically, the longitudinal configuration is characterized by two observable plasmonic phenomena, each sensitive to a different BSA concentration range, ranging from pM to µM. This aspect plays a key role in several biochemical sensing applications, where a wide working range is required.
摘要:
在特定的生物传感应用中,纳米等离子体传感器芯片已经通过基于铝支架和用于照明和收集透射光的两个塑料光纤的实验装置进行了测试。所研究的等离子体探针基于金纳米光栅,在聚(甲基丙烯酸甲酯)(PMMA)芯片的顶部实现。PMMA基板可视为透明基板,以这样的方式,它已经在以前的工作中使用。或者,这里它被认为是一个平板波导。特别是,我们沉积在平板表面,覆盖着纳米光栅,一种对牛血清白蛋白(BSA)具有特异性的合成受体,测试所提出的生物传感方法。利用这种不同的实验配置,我们已经确定了形成光栅图案的纳米条纹的方向,相对于输入光的方向(纵向或正交),影响生物传感性能。例如,已获得的BSA检测中的最佳检测限(LOD)等于23pM。具体来说,纵向构型的特征是两个可观察到的等离子体现象,每个对不同的BSA浓度范围敏感,范围从pM到µM。这一方面在几个生化传感应用中起着关键作用,一个广泛的工作范围是必需的。