Molecularly Imprinted Polymers-Coated CdTe Quantum Dots for Highly Sensitive and Selective Fluorescent Determination of Ferulic Acid

Abstract

Ferulic acid (FA), an important phenolic acid, is widely distributed in higher plants and presents many pharmacological effects. Therefore, sensitive determination of FA in complex matrix is necessary. Molecularly imprinted polymers-coated CdTe quantum dots (CdTe-QDs@MIPs) exhibited incomparable advantages because of their combination of excellent selectivity of MIPs and high sensitivity of QDs. Here, a fluorescent probe based on CdTe-QDs@MIPs was successfully fabricated for selective and sensitive determination of FA. MIPs shell was obtained by the reverse microemulsion method using FA, 3-(aminopropyl) triethoxysilane (APTES), and tetraethyl orthosilicate (TEOS), as template, functional monomer, and crosslinker. In optimal conditions, the fluorescence CdTe-QDs@MIPs sensor exhibited fast response (within only 3 min), high sensitivity (limit of detection, LOD at 0.85 μg/l), excellent linear ranges (2–100 μg/l) with a correlation coefficient of 0.9996, and distinguished selectivity for FA. Satisfactory recoveries from 91.8% to 110.3% were achieved with precisions below 6.6% for FA analysis in real pineapple juice and apple juice by developed CdTe-QDs@MIPs. The fluorescence results coincided well with those obtained by high-performance liquid chromatography (HPLC). It could be concluded that the resultant CdTe-QDs@MIPs offered a new way for rapid and sensitive analysis of FA in the complex matrix.

Molecularly Imprinted Polymers in Biological Applications

“…With the current rapid development of fluorescence imaging technologies coupled with other multimodal approaches (fluorescence/magnetic resonance imaging) [141], MIPs play an important role as a new labeling agent. MIP imaging uses imprinted polymer particles linked with dyes (QDs, carbon dots or conjugated polymers) to yield higher stability or avoid photobleaching, as these issues are rather present when working with fluorescently labeled antibodies [68,142]. Cecchini et al used MIPs coupled with Cd QDs (QD-MIPs) to localize VEGF, responsible for tumor angiogenesis, in zebrafish.…”

Recent Advances and Future Prospects of Molecular Imprinting Polymers as a Recognition Sensing System for Food Analysis: A Review

“…For sol-gel imprinting, (3-aminopropyl)triethoxy silane (APTES) was chosen as a functional monomer because of its amino group that interacts with templates via hydrogen bonds. Tetraethoxysilane acts as a crosslinker to form a polymeric siloxane network through the Si-O bond via hydrolysis [87]. The selection of EGDMA as a cross-linker for the preparation of a novel nanomaterial of the Ni(OH) 2 nanoarrays electrode was applied as a sensing platform for the detection of sulfapyridine in MIP-based electrochemical sensors [88].…”

Biosensors and Sensing Systems for Rapid Analysis of Phenolic Compounds from Plants: A Comprehensive Review

“…Fluorescence intensity of CDs@MIPs decreased linearly with the increase of caffeic acid in the range between 0.5 and 200 μM with a LOD of 0.11 μM, and the proposed method was successfully applied to the detection of caffeic acid in spiked human plasma. One year later, a fluorescent probe based on CdTe-QDs@MIPs was proposed for selective and sensitive determination of ferulic acid, obtaining MIP shell using ferulic acid, APTES and TEOS as template, functional monomer, and crosslinker, respectively [ 140 ]. In optimal conditions, the fluorescence of CdTe-QDs@MIPs sensor exhibited extremely fast response, with a LOD of 4.4 nM, excellent linear range between 10 and 515 nM and optimal selectivity for ferulic acid compared to other structural analogues.…”