Direct and Highly Selective Drug Optosensing in Real, Undiluted Biological Samples with Quantum-Dot-Labeled Hydrophilic Molecularly Imprinted Polymer Microparticles

Abstract

Quantum-dot (QD)-labeled hydrophilic molecularly imprinted polymer (MIP) microparticles were prepared for direct and highly selective optosensing of an antibiotic drug (i.e., tetracycline (Tc)) in pure bovine/goat milks and bovine/porcine serums. "Living" CdTe QD-SiO2 composite microparticles with alkyl bromide groups on their surfaces were first obtained via the one-pot sol-gel reaction, and they were subsequently grafted with a Tc-imprinted polymer layer and poly(glyceryl monomethacrylate) brushes via the successive surface-initiated atom transfer radical polymerizations. The resulting MIP microparticles with QD labeling and hydrophilic polymer brushes could function properly in biological samples and showed obvious template-binding-induced fluorescence quenching, which make them a useful fluorescent chemosensor with limits of detection down to 0.14 μM in complex biological media. Moreover, a facile and effective approach was developed based on a newly derived equation to eliminate the false positives of the fluorescent chemosensor and provide it with wider linear detection concentration ranges in comparison with those obtained using the generally adopted Stern-Volmer equation. Furthermore, the fluorescent MIP chemosensor was also successfully applied for directly, sensitively, selectively, and accurately quantifying Tc in biological media, and the average recoveries were in the range of 95%∼105% even when several other drugs and the fluorescently interfering chlortetracycline were present in the samples.

Molecular Imprinting Technology for Biomimetic Assemblies

“…Besides, it was possible to remove Tc from the biological medium directly, precisely, selectively and in a yield of 95% -105% by the MIP-based chemosensor prepared. In these measurements, it was observed that Tc did not interfere with other drugs [103]. Niu et al in the same group suggested a different method for the efficient determination of Tc.…”

“…Polymeric brushes have advantages such as interfacial localization of terminal groups, diffusion control, regulation of steric repulsive forces, control of phase-segregation in response to external stimuli, wetting control, control of protein and cell adsorption, adsorption of molecules, lubrication, and flocculation control [98]. In these measurements, it was observed that Tc did not interfere with other drugs [103]. Niu et al in the same group suggested a different method for the efficient determination of Tc.…”

Designing and controlling the morphology of spherical molecularly imprinted polymers

“…For organic MIPs, surface hydrophilicity modification is necessary. Zhang [70][71][72][73][74][75][76][77][78][79] proposed a strategy to graft hydrophilic polymer brush on the surface of spherical MIPs. Generally, spherical MIPs were first prepared by living precipitation polymerization (RAFTPP 71,73,74 or ARTPP 72 ), then hydrophilic polymer brushes were grown in situ on their surfaces by surface initiated living polymerization.…”

Recent Advances and Perspectives of Molecularly Imprinted Polymer-Based Fluorescent Sensors in Food and Environment Analysis

“…The MIFs have been widely used in food quality and safety analysis. Most of the studies focus on the fluorescence detection of agricultural and veterinary drug residues [9,84], drug residues [85], prohibited additives [86], heavy metals, environmental organic pollutants, and other hazard factors.…”