Chemistry Department, Shiraz University, Shiraz, Iran.
Chemistry Department, Shiraz University, Shiraz, Iran; Medicinal and Natural Products Chemistry Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
Anal Chim Acta. 2021 Jul 25;1170:338654. doi: 10.1016/j.aca.2021.338654. Epub 2021 May 18.
A new colorimetric sensor array based on mixing of Molybdenum disulfide quantum dots (MoS QDs) and organic reagents is introduced in this study. MoS QDs shows a specific and higher affinity to oxygen functionalized volatile compounds like aldehydes and ketones. Therefore, this designed sensor array is used for classification of eight different aldehydes and ketones based on Linear Discriminate Analysis (LDA) at first. The classification accuracy of 96% and 83% was obtained for training and prediction phases, respectively. Then the introduced colorimetric sensor array is used for the semi-quantitative and quantitative analysis of formaldehyde in milk samples. Formaldehyde is an adulteration that is added to the milk for increasing the storage time. Cow milk samples were provided directly from dairy farmer and from supermarkets and were spiked by formaldehyde in the concentration range of 1-25 ppm. The response of sensor array to these samples were analyzed by partial least squares regression (PLS-R) method and were calibrated for concentration of formaldehyde. The PLSR results (R = 0.94 and RMSEC = 2.36) shows that proposed sensor is useable in direct analysis of formaldehyde in milk as a complex matrix.
本研究介绍了一种基于二硫化钼量子点（MoS QDs）与有机试剂混合的新型比色传感器阵列。MoS QDs 对含氧挥发性化合物（如醛类和酮类）具有特异性和更高的亲和力。因此，该设计的传感器阵列首先基于线性判别分析（LDA）用于对 8 种不同醛类和酮类的分类。在训练和预测阶段，分类准确率分别为 96%和 83%。然后，将引入的比色传感器阵列用于牛奶样品中甲醛的半定量和定量分析。甲醛是一种为了延长牛奶储存时间而添加到牛奶中的掺杂物。牛奶奶样直接由奶农和超市提供，并在 1-25ppm 的浓度范围内用甲醛进行了加标。通过偏最小二乘回归（PLS-R）方法分析了传感器阵列对这些样品的响应，并对甲醛浓度进行了校准。PLS-R 结果（R=0.94 和 RMSEC=2.36）表明，所提出的传感器可用于直接分析牛奶中的甲醛，即使是在复杂基质中。
