Significance: For optical methods to accurately assess hemoglobin oxygen saturation in vivo, an independently verifiable tissue-like standard is required for validation. For this purpose, we propose three hemoglobin preparations and evaluate methods to characterize them. Aim: To spectrally characterize three different hemoglobin preparations using multiple spectroscopic methods and to compare their absorption spectra to commonly used reference spectra. Approach: Absorption spectra of three hemoglobin preparations in solution were characterized using spectroscopic collimated transmission: whole blood, lysed blood, and ferrous-stabilized hemoglobin. Tissue-mimicking phantoms composed of Intralipid, and the hemoglobin solutions were characterized using spatial frequency-domain spectroscopy (SFDS) and enhanced perfusion and oxygen saturation (EPOS) techniques while using yeast to deplete oxygen. Results: All hemoglobin preparations exhibited similar absorption spectra when accounting for methemoglobin and scattering in their oxyhemoglobin and deoxyhemoglobin forms, respectively. However, systematic differences were observed in the fitting depending on the reference spectra used. For the tissue-mimicking phantoms, SFDS measurements at the surface of the phantom were affected by oxygen diffusion at the interface with air, associated with higher values than for the EPOS system. Conclusions: We show the validity of different blood phantoms and what considerations need to be addressed in each case to utilize them equivalently.

中文翻译：

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具有不同氧合状态的液体血红蛋白体模的光谱表征

意义：对于准确评估体内血红蛋白氧饱和度的光学方法，需要一个可独立验证的组织样标准进行验证。为此，我们提出了三种血红蛋白制剂并评估了表征它们的方法。目的：使用多种光谱方法对三种不同的血红蛋白制剂进行光谱表征，并将它们的吸收光谱与常用的参考光谱进行比较。方法：溶液中三种血红蛋白制剂的吸收光谱使用光谱准直透射表征：全血、裂解血和亚铁稳定化血红蛋白。由 Intralipid 组成的组织模拟模型，使用空间频域光谱 (SFDS) 和增强灌注和氧饱和度 (EPOS) 技术对血红蛋白溶液进行表征，同时使用酵母消耗氧气。结果：当分别考虑高铁血红蛋白和氧合血红蛋白和脱氧血红蛋白形式的散射时，所有血红蛋白制剂表现出相似的吸收光谱。然而，根据所使用的参考光谱，在拟合中观察到系统差异。对于组织模拟模型，模型表面的 SFDS 测量值受到与空气界面处氧气扩散的影响，其值高于 EPOS 系统。结论：我们展示了不同血液模型的有效性，以及在每种情况下需要考虑哪些因素才能等效地利用它们。