Shen Yingzhuo, Feng Jianzhou, Wang Zheng, Zhu Jiayuan, Xia Jing Wen, Hu Xiaoya, Liu Wei, Xu Qin
Institute of Innovation Materials and Energy, School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
Institute of Molecular Medicine, Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China.
Anal Chem. 2025 Jul 1;97(25):13487-13495. doi: 10.1021/acs.analchem.5c01915. Epub 2025 Jun 23.
The development of dual-recognition and multisignal transduction sensing strategies is critical for achieving precise identification and ultrasensitive detection of small molecule contaminants. In this work, a fluorescence-photoelectrochemical (FL-PEC) "dual-signal on" sensing platform was presented based on a dual-recognition strategy combining molecularly imprinted polymers (MIPs) and aptamers. Specifically, the MIPs functionalized on the fluorescent carbon dots (CDs) (CDs@MIPs) served as the first recognition element, capturing target molecules and suppressing the photoinduced electron transfer (PET) effect, thereby triggering the fluorescence signal recovery (FL signal). The second recognition units consisted of target-specific aptamer-functionalized liposomes loaded with potassium ferricyanide (Apt@Lip-K[Fe(CN)]), quantitatively binding to the CDs@MIPs/target complex. Subsequent liposome lysis releases K[Fe(CN)], which acted as an electron acceptor to boost the photocurrent of CTAB@MAPbI/ITO, generating a second photoelectrochemical signal increase (PEC signal). Using dibutyl phthalate (DBP) as a model contaminant, the dual-signal platform realized sensitive detection in the linear range of 0.1 nM-10.0 μM (FL) and 1.0 pM-0.1 μM (PEC), with detection limits of 71.30 pM (FL) and 0.648 pM (PEC) (S/N = 3), respectively. The MIPs-aptamer cooperative dual-recognition mechanism enabled complementary FL (rapid visual screening) and PEC (precise quantification) responses, ensuring cross-validated detection that minimizes false positives while enhancing sensitivity. The platform has also been applied for bisphenol A (BPA), another small molecule phenolic pollutant, showing its wide applicability as a universal platform for the detection of small molecule contaminants in food and environmental monitoring applications.
双识别和多信号转导传感策略的发展对于实现小分子污染物的精确识别和超灵敏检测至关重要。在这项工作中，基于分子印迹聚合物（MIP）和适体相结合的双识别策略，提出了一种荧光 - 光电化学（FL - PEC）“双信号开启”传感平台。具体而言，功能化在荧光碳点（CDs）上的MIP（CDs@MIPs）作为第一个识别元件，捕获目标分子并抑制光致电子转移（PET）效应，从而触发荧光信号恢复（FL信号）。第二个识别单元由负载铁氰化钾的目标特异性适体功能化脂质体（Apt@Lip - K[Fe(CN)]）组成，与CDs@MIPs/目标复合物进行定量结合。随后脂质体裂解释放出K[Fe(CN)]，其作为电子受体增强了CTAB@MAPbI/ITO的光电流，产生第二个光电化学信号增加（PEC信号）。以邻苯二甲酸二丁酯（DBP）作为模型污染物，该双信号平台在0.1 nM - 10.0 μM（FL）和1.0 pM - 0.1 μM（PEC）的线性范围内实现了灵敏检测，检测限分别为71.30 pM（FL）和0.648 pM（PEC）（S/N = 3）。MIP - 适体协同双识别机制实现了互补的FL（快速目视筛选）和PEC（精确定量）响应，确保了交叉验证检测，最大限度地减少假阳性同时提高灵敏度。该平台还被应用于另一种小分子酚类污染物双酚A（BPA），显示出其作为食品和环境监测应用中检测小分子污染物的通用平台的广泛适用性。
