Development and optimisation of responsive photoacoustic contrast agents for early detection of cancer

光声成像（PAI）是一种有前途的（预）临床成像方式，检测由短激光脉冲吸收产生的声信号。由于组织和造影剂（CAs）的不同吸收光谱，该技术结合了光学技术的高对比度，以及声学方法的改进穿透深度（高达5厘米），因为声波散射比光子少，使其成为深度，高分辨率3D成像的理想选择。ca可以进一步增强特定区域的信号或报告疾病状态以供诊断。在重点疾病早期诊断的主题下，基于响应性近红外吸收的PAI CAs将用于功能性光声成像。例如，一种在缺氧肿瘤中对硝基还原酶有反应的染料。使用NPL的PA显微镜和正在开发的PAI断层扫描系统，将在癌细胞系和3D球体（可用的乳腺/前列腺模型）和幻影材料中评估优化的ca。我们将建立健全的协议，确保最佳的传输和检测，以最大限度地提高核证机关的反应。NPL、Strathclyde的CAs和GSK的药物开发应用的密切合作将意味着PAI的方法和工具能够满足利益相关者的需求。

Photoacoustic imaging (PAI) is a promising (pre)clinical imaging modality that detects acoustic signals generated by absorption of short laser pulses. The technique combines the high contrast of optical techniques, due to different absorption spectra of tissue and contrast agents (CAs), with the improved penetration depth (up to 5 cm) of acoustic methods, as acoustic waves scatter less than photons, making it ideal for deep, high-resolution 3D imaging. CAs can further enhance signal in specific regions or report on disease states for diagnosis.Within the Early Diagnosis of Priority Diseases theme, PAI CAs based on responsive near-infrared-absorbing will be developed for functional photoacoustic imaging. For example, a dye responsive to the nitroreductase enzyme that is upregulated in hypoxic tumours. Optimised CAs will be evaluated in cancer cell lines and 3D spheroids (breast/prostate models available) and phantom materials using NPL's PA microscope and in-development PAI tomography system. We will establish robust protocols that ensure optimum transmission and detection to maximise the response of the CAs. Close collaboration on development of hardware at NPL, CAs at Strathclyde, and drug-development applications at GSK will mean the PAI methods and tools delivered meet stakeholder needs.