在近红外光谱无创生化检测中, 血流容积光谱相减方法在理论上可以消除组织背景等干扰因素, 提取出血液的有效光谱信息。 为论证血流容积光谱相减方法有效性, 设计了相应的模拟实验。 采用生物分子水溶液模拟血清样品, 不同吸收特性的滤光片模拟组织背景干扰, 可变厚度样品池模拟血流容积变化。 比较了光谱相减方法处理前后的模型精度, 处理前模型定标相关系数(Rc)为0.476, 交叉检验标准差(RMSECV)为437 mg·dL-1; 处理后Rc达到0.977, RMSECV降至301 mg·dL-1。 实验结果表明血流容积光谱相减方法能够较好抑制或扣除组织背景干扰, 大幅度提高模型预测精度。

In noninvasive biochemical detection, the differential spectrum method based on the change in blood volume can eliminate the interference of human tissue background in theory, and obtain effective spectrum information of blood. In order to demonstrate the effectiveness of the differential spectrum method, simulated experiment was designed. Biological molecules solutions were used for simulating serum sample, filters with different absorption characteristic were used for simulating interference of tissue background, and an adjustable path-length cell was used for simulating blood volume change. Model accuracies of pre- and post-treatment with differential spectrum method were compared. Thus treated, the root mean square error of cross validation (RMSECV) reduced from 437 to 301 mg·dL-1. The experimental results indicate that using the differential spectrum method can effectively restrain the interference of tissue background, and greatly improve the prediction precision of calibration model.