In this paper, in vivo spectra from 23 patients’ blood samples with various Creatinine (Cr) concentration levels ranging from 0.96 to 12.5 mg/dL were measured using Fourier transform near-infrared spectrometer (FT-NIRS) and spectrum quantitative analysis method. Since Cr undergoes passive filtration, it serves as a key biomarker of kidneys function via the estimation of glomerular filtration rate. Thus, increased blood Cr concentration reflects impaired renal function. After spectra pre-processing and outlier exclusion, a spectral model was developed based on partial least squares regression (PLSR) method, wherein Cr concentrations correlated with filtered NIR spectra across several peaks, where Cr is known to absorb NIR light. Several statistical metrics were applied to estimate the model efficiency during data analysis. Comparison of spectra-derived concentrations to reference Cr measurements by the current gold-standard Jaffe’s method held in hospital lab revealed a Cr prediction accuracy of 1.64[Formula: see text]mg/dL with good correlation of [Formula: see text]. Bland-Altman plots were used to compare between our calculations and reference lab values and reveal minimal bias between the two. The finding presented the potential of FT-NIRS coupled with PLSR technique for Cr determination.

中文翻译：

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傅里叶 NIR 光谱法和多变量分析法测定患者血液样本中的肌酐水平，并与生化测定法进行比较

本文采用傅里叶变换近红外光谱仪 (FT-NIRS) 和光谱定量分析方法测量了 23 名患者血样的体内光谱，这些血液样本的肌酐 (Cr) 浓度范围从 0.96 到 12.5 mg/dL。由于 Cr 经历被动滤过，它通过估计肾小球滤过率作为肾功能的关键生物标志物。因此，血铬浓度升高反映了肾功能受损。在光谱预处理和异常值排除之后，基于偏最小二乘回归 (PLSR) 方法开发了光谱模型，其中 Cr 浓度与多个峰的过滤 NIR 光谱相关，其中 Cr 已知吸收 NIR 光。在数据分析过程中，应用了几个统计指标来估计模型效率。通过在医院实验室进行的当前金标准 Jaffe 方法将光谱衍生浓度与参考 Cr 测量值进行比较，结果显示 Cr 预测准确度为 1.64[公式：见文本]mg/dL，[公式：见文本]具有良好的相关性。Bland-Altman 图用于比较我们的计算和参考实验室值，并揭示两者之间的最小偏差。该发现展示了 FT-NIRS 与 PLSR 技术相结合用于 Cr 测定的潜力。