Yang Feng, Qi Xin, Chen Yan, Tang Kai, Fang Mengyang, Song Yanwei, Liu Jiufen, Zhang Lianming
Haikou Key Laboratory of Marine Contaminants Monitoring Innovation and Application, Haikou Marine Geological Survey Center, China Geological Survey, Haikou 571127, China.
Command Center for Natural Resources Comprehensive Survey, China Geological Survey, Beijing 100055, China.
Foods. 2025 May 7;14(9):1648. doi: 10.3390/foods14091648.
In this study, β-cyclodextrin (β-CD) functionalized graphene quantum dots (GQDs) was employed to augment the array of chiral recognition sites, thereby enhancing the affinity of GQDs/β-CD composite for imprinting molecules and realizing heightened chiral selectivity. The incorporation of GQDs/β-CD into the synthesis of molecularly imprinted polymers (MIPs), synergizing with the host-guest inclusion properties of β-CD and the abundant carboxyl groups of GQDs, enhanced the chiral recognition capacity of MIPs materials. Consequently, a novel MIPs/(GQDs/β-CD) sensor with chiral recognition capabilities tailored for D-carnitine was successfully fabricated. The binding mechanism between GQDs/β-CD and D-carnitine was elucidated via Ultraviolet-visible spectroscopy and Fourier transform infrared spectroscopy. The variation in the response signal (ΔI) of the probe molecule exhibited a linear correlation with the logarithm of D-carnitine concentration (lgC) in the range of 1.0 × 10 mol/L to 1.0 × 10 mol/L, and the detection limit (3δ/S) was calculated as 2.35 × 10 mol/L. These results underscore a 7.15-fold enhancement in the selectivity of MIPs/(GQDs/β-CD) sensor for D-carnitine recognition. Moreover, the sensor presented commendable efficacy in real-world scenarios, yielding recovery rates ranging from 98.5% to 103.0% during the determination of D-carnitine content in real samples.
在本研究中，采用β-环糊精（β-CD）功能化的石墨烯量子点（GQDs）来增加手性识别位点的数量，从而提高GQDs/β-CD复合材料对印迹分子的亲和力，并实现更高的手性选择性。将GQDs/β-CD引入分子印迹聚合物（MIPs）的合成中，与β-CD的主客体包合性质和GQDs丰富的羧基协同作用，增强了MIPs材料的手性识别能力。因此，成功制备了一种针对D-肉碱具有手性识别能力的新型MIPs/（GQDs/β-CD）传感器。通过紫外可见光谱和傅里叶变换红外光谱阐明了GQDs/β-CD与D-肉碱之间的结合机制。探针分子的响应信号变化（ΔI）与D-肉碱浓度的对数（lgC）在1.0×10⁻⁶mol/L至1.0×10⁻²mol/L范围内呈线性相关，检测限（3δ/S）计算为2.35×10⁻⁷mol/L。这些结果表明MIPs/（GQDs/β-CD）传感器对D-肉碱识别的选择性提高了7.15倍。此外，该传感器在实际应用中表现出良好的效果，在测定实际样品中D-肉碱含量时，回收率在98.5%至103.0%之间。
