傅里叶变换红外光谱结合衰减全反射技术用于地贫筛查指标的无试剂定量分析

利用傅里叶变换红外光谱(FTIR)和衰减全反射(ATR)结合偏最小二乘(PLS)回归，建立地中海贫血(地贫)筛查指标平均红细胞血红蛋白含量(MCH)、平均红细胞体积(MCV)和总血红蛋白(Hb)的同时定量分析方法。收集人外周血样品380个，根据地贫血液学指标筛查标准，地贫阳性180个、阴性200个。从全体样品中随机选取150个为检验集(阴性64，阳性86)，余下230个为建模集(阴性136、阳性94);再将建模集随机划分为定标集(阴性68、阳性47，共计115)、预测集(阴性68、阳性47，共计115)，共200次。实验比较的结果表明，中红外指纹区(1 600～900 cm-1)PLS模型的预测效果显著优于全扫描谱区(4 000～600 cm-1)PLS模型，并且模型复杂性明显降低。基于中红外指纹区PLS模型，MCH，MCV，Hb最优PLS因子个数分别为10, 10, 6;建模预测均方根误差(M_SEP_Ave)分别为2.19 pg，5.13 fL，8.0 g·L-1;建模预测相关系数(M_R_{P, Ave})分别为0.902，0.898，0.922;检验预测均方根误差(V_SEP)分别为2.22 pg，5.38 fL，7.7 g·L-1;检验预测相关系数(V_R_P)分别为0.900，0.895，0.929;地贫筛查灵敏度、特异性分别达到100.0%和95.3%。结论：FTIR/ATR光谱结合PLS方法可以提供一种无需试剂、快速简便的大人群地贫筛查新技术。

Fourier Transform Infrared Spectroscopy Combined with Attenuated Total Reflection Applied to Reagent-Free Quantitative Analysis of Thalassemia Screening Indicators

A simultaneous quantitative analysis method for the thalassemia screening indicators mean corpuscular hemoglobin (MCH), mean corpuscular volume (MCV), and hemoglobin (Hb) was developed with Fourier transform infrared (FTIR) spectrometers and attenuated total reflection (ATR) combined with partial least squares (PLS). A total of 380 human peripheral blood samples were collected, which were composed of 180 positive samples and 200 negative samples according to the criteria of hematological indicator screening for thalassemia. One hundred fifty samples (64 negative, 86 positive) were randomly selected from all samples as the validation set, the remaining 230 samples (136 negative, 94 positive) were used as modeling samples; and then the modeling set was further subdivided into calibration set (68 negative, 47 positive, and 115 in total) and prediction set (68 negative, 47 positive, and 115 in total) for 200 times. Comparison of experimental results show that the prediction effect of PLS models in mid-infrared (MIR) fingerprint region (1 600～900 cm-1) was significantly better those of PLS models in the full scanning region (4 000～600 cm-1), and model complexity is significantly reduced. Based on PLS model in MIR fingerprint region, the optimal numbers of PLS factors for MCH, MCV and Hb were 10, 10 and 6, respectively, and the root mean square error (M_SEP_Ave) and the correlation coefficient (M_R_{P, Ave}) of prediction in the modeling set were 2.19 pg, 0.902 for MCH, 5.13 fL, 0.898 for MCV and 8.0 g·L-1, 0.922 for Hb, respectively. The root mean square error (V_SEP) and the correlation coefficient (V_R_P) of prediction in the validation set were 2.22 pg, 0.900 for MCH, 5.38 fL, 0.895 for MCV and 7.7 g·L-1, 0.929 for Hb, respectively. The sensitivity and specificity for thalassemia screening achieved 100.0% and 95.3%, respectively. Conclusion: FTIR/ATR spectroscopy combined with PLS method could provide a new reagent-free and rapid technique for thalassemia screening for large populations.