Mid-infrared (IR), Raman, and X-ray fluorescence (XRF) spectroscopy methods, as well as mass spectrometry (MS), can be used for 3D chemical imaging. These techniques offer an invaluable opportunity to access chemical features of biological samples in a nonsupervised way. The global chemical information they provide enables the exploitation of a large array of chemical species or parameters, so-called ‘spectromics’. Extracting chemical data from spectra is critical for the high-quality chemical analysis of biosamples. Furthermore, these are the only currently available techniques that can quantitatively analyze tissue content (e.g., molecular concentrations) and substructures (e.g., cells or blood vessels). The development of chemical-derived biological metadata appears to be a new way to exploit spectral information with machine learning algorithms.

中红外（IR），拉曼和X射线荧光（XRF）光谱方法以及质谱（MS）可用于3D化学成像。这些技术为以非监督方式访问生物样品的化学特征提供了宝贵的机会。他们提供的全球化学信息可以利用各种化学物种或参数，即所谓的“光谱学”。从光谱中提取化学数据对于生物样品的高质量化学分析至关重要。此外，这些是目前唯一可以定量分析组织含量（例如分子浓度）和子结构（例如细胞或血管）的技术。