Development of functionalised nanoparticles for cancer imaging using surface enhanced spatially offset resonance Raman spectroscopy

空间偏移拉曼光谱（SORS）是一种用于对内容物被不透明层或容器遮挡的物体进行准确和可靠的化学分析的方法，例如用于筛选机场的爆炸物容器内容物。它包括用入射激光束询问样品并测量距离照明区域偏移距离的散射光，这允许从样品内部深处获得拉曼响应。深拉曼技术的进一步发展导致了表面增强拉曼散射（SERS）和传感器的结合，称为感应器。由于可以实现增强的拉曼响应，这为在更深的深度检测许多分析物开辟了道路。我们最近的论文介绍了SESORS的概念，通过展示从深埋的SERS纳米颗粒探测信号的可能性，达到了深拉曼光谱的一个关键里程碑，或者从比以前在外拉曼方法中实现的更深（25毫米）的深度注射到组织中。我们与Dstl的首次合作也在最近发布，使用了一个手动帮助或辅助设备。该项目与Dstl合作，将使用Dstl提供的便携式传感器系统，评估在一系列屏障（如厚塑料（1-5毫米厚）、彩色玻璃和纸板）后检测SERS纳米标签的能力。这将涉及开发适当标记的SERS活性纳米标签，该纳米标签在785 nm及以上具有强烈的SERS响应。这将需要合成不同类型的金属纳米粒子，这些金属纳米粒子对电磁纳米粒子的红外区域具有吸光度，并为纳米粒子开发在环境中稳定的涂层，这些纳米粒子将作为标签。这将涉及探索标记纳米粒子的封装，例如不同的聚合物或二氧化硅。然后，这些将用于不同的屏障材料，不同的，已知的，厚度，并用于优化每种材料的传感器/感应器系统。一旦该系统经过优化，能够在深度处提供最大的SERS响应，该系统也将用于检测生物材料内部的纳米标签。例如，在组织内部检测纳米标签来模拟体内目标纳米标签的检测。目的(1)探索红移吸光度金属纳米标签的合成方法。这将涉及合成具有不同尺寸、形状和外壳结构的纳米颗粒。(2)评估可用于保护或封装标记纳米颗粒并保护其免受环境影响的基质，并研究其在785 nm及以上激光激发下的使用情况。(3)在各种容器（如塑料、玻璃、纸等）中使用传感器对分析物和SERS活性纳米标签进行拉曼检测。容器的厚度也会有所不同。(4)在生物材料（如组织样品）内部深度检测纳米标签。

Spatially offset Raman spectroscopy (SORS) is a method used for accurate and robust chemical analysis of objects where the contents are obscured by an opaque layer or container for example for screening the contents of containers at airports for explosives. It involves interrogating a sample with an incident laser beam and measuring the scattered light at a distance offset from the illumination area, this allows Raman responses to be obtained from at depth within a sample. Further advances in deep Raman techniques have led to the combination of both surface enhanced Raman scattering (SERS) and SORS together, referred to as SESORS. This opens the way for detecting a number of analytes at even greater depths due to the enhanced Raman response achievable. Our recent paper introducing the concept of SESORS, reached a key milestone in deep Raman spectroscopy by demonstrating the possibility of probing signals from SERS nanoparticles buried, or injected into tissues from depths significantly deeper (25 mm) than that previously achieved in epi-Raman approaches. Our initial collaboration with Dstl using a hand help SORS device was also recently published.This project, in collaboration with Dstl will use a portable SORS system supplied by Dstl, to assess the ability to detect SERS nanotags behind a range of barriers, such as thick plastics (1-5 mm thick), coloured glass and cardboard. This will involve developing suitably labelled SERS active nanotags which give a strong SERS response at 785 nm and above. 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 which are stable in the environment in which they will act as a label. This will involve exploring the encapsulation of labelled nanoparticles in for example different polymers or silica. These will then be used inside different barrier materials, of varying, known, thickness, and used to optimise the SORS/SESORS system for each material.Once the system has been optimised to give maximum SERS response at depth, the system will also be used for the detection of nanotags inside biological material. For example, the detection of nanotags inside tissue to simulate the detection of target nanotags in vivo.Objectives(1) To explore the synthesis of metal nanotags with red shifted absorbances. This will involve synthesising nanoparticles with different sizes, shapes and shell structures.(2) Evaluate matrices which can be used to protect or encapsulate the labelled nanoparticles and protect them from the environment and investigate their use with 785 nm laser excitation and above.(3) Raman detection of analytes and SERS active nanotags using SORS in various containers made of for example plastic, glass, paper etc. The thickness of the containers will also be varied.(4) SORS detection of nanotags at depth within biological material e.g. tissue samples.