Development of optically bright nanotags for SERS

表面增强拉曼散射是一种非常灵敏和选择性的技术，正迅速成为超灵敏分析的一种有效方法。它提供了比正常拉曼散射增加的增强，因此是检测痕量分析物的理想选择，并且由于获得的分子特异性光谱，它是检测混合物中的分析物的理想选择。SERS的灵敏度也使其能够经得起检测，因为可以从特殊合成的标签以及商业上可用的标签中获得强烈的信号。这些标签与纳米颗粒结合使用，由于其独特的振动光谱，可以在饮料市场等品牌保护领域对产品进行标签。该项目建议开发使用785纳米或更高激发波长进行编码纳米粒子检测所需的技术和标签。这将需要合成不同类型的金属纳米颗粒，这些金属纳米颗粒对电磁纳米颗粒的红外区域具有吸光度，并为纳米颗粒开发涂层，以保护它们免受恶劣环境（如强酸）的影响，同时仍然能够产生强烈的SERS响应。然后，我们将开发制造和优化纳米粒子的方法，以提供最强（最亮）的SERS信号。这可能需要分离程序，例如使用简单的流体或分离系统，将最亮的纳米颗粒与SERS活性较弱的纳米颗粒分离，以丰富SERS反应。纳米粒子将被涂上二氧化硅，以使它们在充当标签的环境中保持强烈的SERS活性和稳定性。然后，我们将使用这些明亮的、环境稳定的纳米颗粒来检测医疗环境中的整个细菌。

Surface enhanced Raman scattering is an extremely sensitive and selective technique that is rapidly emerging as an effective method for ultrasensitive analysis. It offers an increased enhancement over normal Raman scattering therefore is ideal for the detection of trace amounts of analyte and because of the molecularly specific spectra obtained it is ideal for detecting analytes in mixtures. The sensitivity of SERS also lends itself to stand off detection due to the intense signals which can be obtained from specially synthesised labels as well as ones which are commercially available. These labels, in combination with nanoparticles, can be used as coded labels due to their unique vibrational spectra allowing labelling of products in areas such as brand protection for example in the beverage market.This project proposes to develop the technique and labels required to carry out detection of coded nanoparticles using an excitation wavelengths of 785 nm or higher. This will require synthesising different types of metal nanoparticles which have absorbances towards the infrared region of the electromagnetic nanoparticles and developing coatings for the nanoparticles that would protect them from harsh environments such as strong acid, while still being able to give a strong SERS response. We will then develop ways to make and optimise the nanoparticles to give the strongest (brightest) SERS signal possible. This may require separation procedures, for example using simple fluidics or separation systems, to separate the brightest nanoparticles from ones that are more weakly SERS active to enrich the SERS response. The nanoparticles will be cpated with, most likely, silica to allow them to remain strongly SERS active and stable to the environment in which they will act as a label. We will then use these bright, environmentally stable nanoparticles for the detection of whole bacteria in the healthcare environment.