A novel molecularly imprinted quartz crystal microbalance (QCM) sensor was successfully prepared for selective determination of sialic acid (SA) in human urine samples. To obtain the QCM sensor, we first modified the gold surface of the QCM chip by self-assembling of allylmercaptane to introduce polymerizable double bonds on the chip surface. Then, SA molecularly imprinted polymer (MIP) nanofilm was attached to the modified QCM chip surface. For comparison, we have also characterized the nonmodified and improved surfaces of the QCM sensor by using atomic force microscopy (AFM) and Fourier transform infrared (FTIR) spectroscopy. We then tested the selectivity and detection limit of the imprinted QCM sensor via a series of adsorption experiments. The results show a linear response in the range of 0.025–0.50 μmol L⁻¹ for sialic acid. Moreover, the limit of detection (LOD) of the prepared imprinted QCM sensor was found to be 1.0 nmol L⁻¹ for sialic acid, and high recovery values range from 87.6 to 108.5% with RSD < 8.7 (n = 5) for the spiked urine sample obtained. Overall, this work presents how a novel QCM sensor was developed and used to detect sialic acid in human urine samples.

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成功地制备了一种新型分子印迹石英晶体微天平（QCM）传感器，用于选择性测定人尿液样品中的唾液酸（SA）。为了获得QCM传感器，我们首先通过烯丙基硫醇的自组装修饰QCM芯片的金表面，以在芯片表面引入可聚合的双键。然后，将SA分子印迹聚合物（MIP）纳米膜附着到改性的QCM芯片表面。为了进行比较，我们还通过使用原子力显微镜（AFM）和傅立叶变换红外（FTIR）光谱对QCM传感器的未经修饰和改进的表面进行了表征。然后，我们通过一系列吸附实验测试了印迹QCM传感器的选择性和检测极限。结果表明，线性响应的范围为0.025–0.50μmolL ^-1用于唾液酸。此外，发现所制备的印迹QCM传感器的检测限（唾液酸为1.0 nmol L ^-1），高回收率的范围为87.6至108.5％， 加标的RSD <8.7（n = 5）获得尿液样本。总的来说，这项工作介绍了如何开发新型QCM传感器并将其用于检测人尿液样品中的唾液酸。

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