Molecular Imprinting Research Articles

SYNTHESIS OF TETRACYCLINE IMPRINTED POLYMERS WITH METHACRYLIC ACID AS FUNCTIONAL MONOMER IN METHANOL-CHLOROFORM MIXTURE USING BULK AND PRECIPITATION POLYMERIZATION METHOD

The content of tetracycline residues in poultry meat products can cause antibiotic resistance in humans who consume these products, so it is necessary to develop sensitive analytical techniques to determine the levels of tetracycline residues to assess the safety of these products for consumption. The molecular imprinting technique is a method to produce sorbents with molecular recognition capability of target compounds that can be used to increase the selectivity of solid phase extraction to extract tetracycline residues for further analysis. This study aimed to obtain a sorbent synthesized by molecular imprinting technique to analyze tetracycline in poultry meat products. The stages of the research began with the study of the interaction of functional monomers with template molecules, determining the association constants of functional monomers with template molecules, synthesis of imprinted polymer molecules using bulk and precipitation methods, evaluating the ability and adsorption capacity of the synthesized polymers, assess the selectivity of polymers for analog structures and physical characteristics with FTIR. The research showed that methacrylic acid was the best functional monomer with a binding energy value of -27.3776 kcal/mol. The higher adsorption capacity was achieved by Molecularly Imprinted Polymer (MIP) that was synthesized by precipitation method (MIP2) than the other MIP synthesized by bulk polymerization (MIP1) with a value of 0.8748 mg/g and 0.4077 mg/g, respectively. The analogous compounds' imprinting factor values for each MIP were 1.197 and 1.1272. The polymer synthesized by molecular imprinting technique is selective for extracting and analyzing tetracycline from poultry meat matrix.

Computational modelling and optimization studies of electropentamer for molecular imprinting of DJ-1

Parkinson's disease (PD) is the most prevalent type of incurable movement disorder. Recent research findings propose that the familial PD-associated molecule DJ-1 exists in cerebrospinal fluid (CSF) and that its levels may be altered as Parkinson's disease advances. By using a molecularly imprinted polymer (MIP) as an artificial receptor, it becomes possible to create a functional MIP with predetermined selectivity for various templates, particularly for the DJ-1 biomarker associated with Parkinson's disease. It mostly depends on molecular recognition via interactions between functional monomers and template molecules. So, the computational methods for the appropriate choice of functional monomers for creating molecular imprinting electropolymers (MIEPs) with particular recognition for the detection of DJ-1, a pivotal biomarker involved in PD, are undertaken in this study. Here, molecular docking, molecular dynamics simulations (MD), molecular mechanics Poisson–Boltzmann surface area (MM-PBSA) methods, and quantum mechanical calculation have been applied to investigate the intermolecular interaction between DJ-1 and several functional electropentamers, viz., polypyrrole (PPy), poly(3,4-ethylenedioxythiophene) (PEDOT), poly(o-aminophenol) (POAP), and polythiophene (PTS). In this context, the electropentamers were selected to mimic the imprinted electropolymer system. We analyzed the most stable configurations of the formed complexes involving DJ-1 and electropentamers as a model system for MIEPs. Among these, PEDOT exhibited a more uniform arrangement around DJ-1, engaging in numerous van der Waals, H-bond, electrostatic, and hydrophobic interactions. Hence, it can be regarded as a preferable choice for synthesizing a MIP for DJ-1 recognition. Thus, it will aid in selecting a suitable functional monomer, which is of greater significance in the design and development of selective DJ-1/MIP sensors.

Unveiling a pH-Responsive Dual-Androgen-Blocking Magnetic Molecularly Imprinted Polymer for Enhanced Synergistic Therapy of Prostate Cancer.

Prostate cancer is the most common malignancy diagnosed in men. Androgens are directly related to its pathogenesis. Inhibition of the androgen receptor (AR) is considered to be the most promising therapeutic approach for the treatment of prostate cancer. In this study, a new type of pH-responsive dual androgen-blocking nanodrug (FASC MIPs) based on a molecularly imprinted polymer has been designed and synthesized. The nanodrug could selectively sequester testosterone from the prostate tumor through specific molecular imprinting sites and simultaneously deliver the AR inhibitory drug bicalutamide, which ultimately leads to enhanced synergistic therapy of prostate cancer. FASC MIPs demonstrate excellent pH responsiveness in a simulated tumor microenvironment due to the presence of chitosan and significantly inhibit the growth of prostate cancer cells (LNCaP cells) by blocking the G1 phase of cytokinesis. Additionally, the nanodrug also displayed excellent antitumor properties in a xenograft mouse model of prostate cancer without any sign of detrimental effects on healthy tissues and organs. Both in vitro and in vivo studies verified the augmented and synergistic therapeutic effects of FASC MIPs, and the proposed dual-androgen-blocking strategy could explore novel avenues in prostate cancer treatment.

Self-service multimodal detection of subtype influenza A virus H5N1 by visual portable molecular imprinting sensor

At present, the ability to identify subtypes of influenza A virus (IAV) with high similarity in morphology, size, and surface structure is sufferedfrom significant challenges. In this study, we report on the development of a portable, multi-color, colorimetric molecular imprinting polymer (MIP)-based sensor that can specifically identify H5N1. To construct this sensor, using H5N1 as a template, the MIPs was obtained on the Fe3O4@ quantum dots (QDs) prepared in advance. Then, the Fe3+@PDA∼ Apt probe, which was designed for specificity for H5N1, was prepared by modifying the H5N1 ∼ Apt on the surface of the pre-prepared Fe3+-embedded dopamine nanoparticles. A sandwich structure would be formed via the specific combination of MIPs, H5N1 and Fe3+@PDA ∼ Apt. During detection, the fluorescence of QDs quenched, achieving the first detection mode of viruses through the change of fluorescence intensity. Subsequently, Fe3+ in the solution was released, K4[Fe(CN)6] and K3[Fe(CN)6] were added to achieve a multi-color colorimetric detection sensor visible to the naked eyes. The third detection mode can be achieved by detecting the absorbance of the solution by ultraviolet–visible. The sensor was capable of differentiating the target H5N1 virus from other IAV subtypes with high specificity and sensitivity (LOD = 11.6 fM), and the detection of the virus could be enabled by fluorescence spectroscopy, UV–vis spectrophotometry, and colorimetric indication three modes, to provide a reliable point-of-care detection method for ensuring the accurate treatment of patients with H5N1 infection. Importantly, the MIP-based sensor could conveniently achieve the self-service detection at a cost of only RMB in 0.28 yuan.

Bidirectional Regulation of Intracellular Enzyme Activity Using Light-Driven Nano-Inhibitors.

Photochemical regulation provides precise control over enzyme activities with high spatiotemporal resolution. A promising approach involves anchoring "photoswitches" at enzyme active sites to modulate substrate recognition. However, current methods often require genetic mutations and irreversible enzyme modifications for the site-specific anchoring of "photoswitches", potentially compromising the enzyme activities. Herein, we present a pioneering reversible nano-inhibitor based on molecular imprinting technique for bidirectional regulation of intracellular enzyme activity. The nano-inhibitor employs a molecularly imprinted polymer nanoparticle as its body and azobenzene-modified inhibitors ("photoswitches") as the arms. By using a target enzyme as the molecular template, the nano-inhibitor acquires oriented binding sites on its surface, resulting in a high affinity for the target enzyme and non-covalently firm anchoring of the azobenzene-modified inhibitor to the enzyme active site. Harnessing the reversible isomerization of azobenzene units upon exposure to ultraviolet and visible light, the nano-inhibitor achieves bidirectional enzyme activity regulation by precisely docking and undocking inhibitor at the active site. Notably, this innovative approach enables the facile in situ regulation of intracellular endogenous enzymes, such as carbonic anhydrase. Our results represent a practical and versatile tool for precise enzyme activity regulation in complex intracellular environments.

Bidirectional Regulation of Intracellular Enzyme Activity Using Light‐Driven Nano‐Inhibitors

AbstractPhotochemical regulation provides precise control over enzyme activities with high spatiotemporal resolution. A promising approach involves anchoring “photoswitches” at enzyme active sites to modulate substrate recognition. However, current methods often require genetic mutations and irreversible enzyme modifications for the site‐specific anchoring of “photoswitches”, potentially compromising the enzyme activities. Herein, we present a pioneering reversible nano‐inhibitor based on molecular imprinting technique for bidirectional regulation of intracellular enzyme activity. The nano‐inhibitor employs a molecularly imprinted polymer nanoparticle as its body and azobenzene‐modified inhibitors (“photoswitches”) as the arms. By using a target enzyme as the molecular template, the nano‐inhibitor acquires oriented binding sites on its surface, resulting in a high affinity for the target enzyme and non‐covalently firm anchoring of the azobenzene‐modified inhibitor to the enzyme active site. Harnessing the reversible isomerization of azobenzene units upon exposure to ultraviolet and visible light, the nano‐inhibitor achieves bidirectional enzyme activity regulation by precisely docking and undocking inhibitor at the active site. Notably, this innovative approach enables the facile in situ regulation of intracellular endogenous enzymes, such as carbonic anhydrase. Our results represent a practical and versatile tool for precise enzyme activity regulation in complex intracellular environments.

Mycotoxins-Imprinted Polymers: A State-of-the-Art Review.

Mycotoxins are toxic metabolites of molds which can contaminate food and beverages. Because of their acute and chronic toxicity, they can have harmful effects when ingested or inhaled, posing severe risks to human health. Contemporary analytical methods have the sensitivity required for contamination detection and quantification, but the direct application of these methods on real samples is not straightforward because of matrix complexity, and clean-up and preconcentration steps are needed, more and more requiring the application of highly selective solid-phase extraction materials. Molecularly imprinted polymers (MIPs) are artificial receptors mimicking the natural antibodies that are increasingly being used as a solid phase in extraction methods where selectivity towards target analytes is mandatory. In this review, the state-of-the-art about molecularly imprinted polymers as solid-phase extraction materials in mycotoxin contamination analysis will be discussed, with particular attention paid to the use of mimic molecules in the synthesis of mycotoxin-imprinted materials, to the application of these materials to food real samples, and to the development of advanced extraction methods involving molecular imprinting technology.

Biosensing Applications of Molecularly Imprinted-Polymer-Based Nanomaterials

In the realm of sensing technologies, the appeal of sensors lies in their exceptional detection ability, high selectivity, sensitivity, cost-effectiveness, and minimal sample usage. Notably, molecularly imprinted polymer (MIP)-based sensors have emerged as focal points of interest spanning from clinical to environmental applications. These sensors offer a promising avenue for rapid, selective, reusable, and real-time screening of diverse molecules. The preparation technologies employed in crafting various polymer formats, ranging from microparticles to nanomaterials, wield a profound influence. These techniques significantly impact the assembly of simplified sensing systems, showcasing remarkable compatibility with other technologies. Moreover, they are poised to play a pivotal role in the realization of next-generation platforms, streamlining the fabrication of sensing systems tailored for diverse objectives. This review serves as a comprehensive exploration, offering concise insights into sensors, the molecular imprinting method, and the burgeoning domain of MIP-based sensors along with their applications. Delving into recent progress, this review provides a detailed summary of advances in imprinted-particle- and gel-based sensors, illuminating the creation of novel sensing systems. Additionally, a thorough examination of the distinctive properties of various types of MIP-based sensors across different applications enriches the understanding of their versatility. In the concluding sections, this review highlights the most recent experiments from cutting-edge studies on MIP-based sensors targeting various molecules. By encapsulating the current state of research, this review acts as a valuable resource, offering a snapshot of the dynamic landscape of MIP-based sensor development and its potential impact on diverse scientific and technological domains.

Basic Electrochemistry Meets Molecular Recognition: Hands-On Experiment of Cortisol Detection Using Carbon Paste Electrode Prepared by Molecular Imprinting Technology for Undergraduates

Basic Electrochemistry Meets Molecular Recognition: Hands-On Experiment of Cortisol Detection Using Carbon Paste Electrode Prepared by Molecular Imprinting Technology for Undergraduates

Rapid and Efficient detection of perfluorooctanoic acid by up–conversion molecular imprinting fluorescent probe

Perfluorooctanoic acid (PFOA) is a persistent pollutant that is hazardous and bioaccumulates, seriously harming both the environment and humans. However, detecting PFOA in a sensitive, affordable and pollution–free way remains a challenge. This work combines up–conversion luminescent materials and molecularly imprinted polymers (MIPs) to prepare up–conversion molecularly imprinted fluorescent probe NH2–NaYF4: Yb3+, Ho3+@MIP, using NaYF4:Yb3+, Ho3+ as the luminescent signal source with a mesoporous structure. The PFOA and the probes generate fluorescence quenching based on the F–F interaction and electrostatic adsorption. This can sensitively detect 0.05–15 nmol/l PFOA in aqueous solution. This work provides a fresh and practical method for detecting PFOA in aqueous solutions.

The Failure of Molecular Imprinting in Conducting Polymers: A Case Study of Imprinting Picric Acid on Polycarbazole.

The aims of this study were to investigate the potential of utilising molecularly imprinted polycarbazole layers to detect highly toxic picric acid (PA) and to provide information about their performance. Quantum chemical calculations showed that strong interactions occur between PA and carbazole (bond energy of approximately 31 kJ/mol), consistent with the theoretical requirements for effective molecular imprinting. The performance of the sensors, however, was found to be highly limited, with the observed imprinting factor values for polycarbazole (PCz) layers being 1.77 and 0.95 for layers deposited on Pt and glassy carbon (GC) electrodes, respectively. Moreover, the molecularly imprinted polymer (MIP) layers showed worse performance than unmodified Pt or GC electrodes, for which the lowest limit of detection (LOD) values were determined (LOD values of 0.09 mM and 0.26 mM, respectively, for bare Pt and MIP PCz/Pt, as well as values of 0.11 mM and 0.57 mM for bare GC and MIP PCz/GC). The MIP layers also showed limited selectivity and susceptibility to interfering agents. An initial hypothesis on the reasons for such performance was postulated based on the common properties of conjugated polymers.

Fluorescent Probes Based on Ag NPs@N/GQDs and Molecularly Imprinted Polymer for Sensitive Detection of Noradrenaline in Bananas.

Fluorescence intensity and selective recognition ability are crucial factors in determining the analytical techniques for fluorescent probes. In this study, a core-shell fluorescent material, composed of silver nanoparticles@nitrogen-doped graphene quantum dots (Ag NPs@N/GQDs), was synthesised using mango leaves as the raw material through a thermal cracking method, resulting in strong fluorescence luminescence intensity. By employing noradrenaline as a template molecule and using a surface molecular imprinting technique, a molecularly imprinted membrane (MIP) was formed on the surface of the fluorescent material, that was subsequently eluted to obtain a highly specific, fluorescent probe capable of recognising noradrenaline. The probe captured various concentrations of noradrenaline using the MIP, which decreased the fluorescence intensity. Then a method for detecting trace amounts of noradrenaline was established. This method exhibited a linear range from 0.5 -700pM with a detection limit of 0.154pM. The proposed method was implemented in banana samples. Satisfactory recoveries were confirmed at four different concentrations. The method presented a relative standard deviation (RSD) of less than 5.0%.

Development and evaluation of ciprofloxacin local controlled release materials based on molecularly imprinted polymers

The aim of this study was the molecular imprinting polymers (MIPs) assessment as a controlled release system of ciprofloxacin. The MIPs synthesis was performed by three different methods: emulsion, bulk, and co-precipitation. Lactic acid (LA) and methacrylic acid (MA) were used as functional monomers and ethylene glycol dimethacrylate as crosslinker. Also, nonimprinted polymers (NIPs) were synthesized. MIPs and NIPs were characterized by scanning electron microscopy, Fourier Transform Infrared Reflection, specific surface area, pore size, and release kinetics. Their efficiency against Staphylococcus aureus and Escherichia coli, and their cytotoxicity in dermal fibroblast cells were proven. Results show that MIPs are mesoporous materials with a pore size between 10 and 20 nm. A higher adsorption with the co-precipitation MIP with MA as a monomer was found. The release kinetics proved that a non-Fickian process occurred and that the co-precipitation MIP with LA presented the highest release rate (90.51 mg/L) in 8 h. The minimum inhibitory concentration was found between 0.031 and 0.016 mg/L for Staphylococcus aureus and between 0.004 and 0.031 mg/L for the Escherichia coli. No cytotoxicity in cellular cultures was found; also, cellular growth was favored. This study demonstrated that MIPs present promising properties for drug administration and their application in clinical practice.

A SERS-assisted 3D organotypic microfluidic chip for in-situ visualization and monitoring breast cancer extravasation process

Extravasation, as one of the key steps in cancer metastasis, refers to the process where tumor cells escape the bloodstream by crossing the vascular endothelium and invade the targeted tissue, which accounts for the low five-year survival rate of cancer patients. Understanding the mechanism of cancer metastasis and inhibiting extravasation are crucial to improve patient prognosis. Here, a 3D organotypic microfluidic chip combined with SERS-based protein imprinted nanomaterials (SPINs) was proposed to study the extravasation process in vitro. The chip consists of a collagen gel channel and a vascular channel where human vein endothelial cells (HUVECs) and breast cancer cells are injected sequentially to induce extravasation. By comparing two subtypes of breast cancer cells (MCF-7 and MDA-MB-231), we successfully observed the difference in extravasation capabilities between two kinds of cells through fluorescence imaging. Meanwhile, thanks to the high specificity of molecular imprinting technology and the high sensitivity of surface enhanced Raman scattering (SERS), SPINs were utilized to analyze the concentration of several cancer secretions (interleukin-6 and interleukin-8) in complex biological fluid in real-time. Further, our model showed that downregulation of secretions by therapeutic drugs can inhibit the extravasation of breast cancers. This microfluidic model may pave the way for the fundamental research of the cancer metastasis and evaluating the therapeutic efficacy of potential drugs.

A More Efficient Method for Preparing a MIP-CQDs/ZnO1-x Photodegradant with Highly Selective Adsorption and Photocatalytic Properties.

The application of semiconductor photocatalysts in wastewater treatment always has a drawback, which is the lack of selectivity for pollutants, but molecular imprinting technology (MIT) is a remarkable method for preparing highly selective adsorbents for low concentration target pollutants. Up to now, the research of molecular imprinting materials has mainly focused on organic polymers, and there has been little research on inorganic molecular imprinting materials. In the present work, we introduced carbon quantum dots (CQDs) into the flower-like hierarchical ZnO to prepare photocatalysts CQDs/ZnO. Further, with ciprofloxacin (CIP) as the template molecule, a molecular imprinting material MIP-CQDs/ZnO1-x was prepared by introducing both oxygen vacancies and imprinted cavities into CQDs/ZnO by the hydrothermal calcination method. It can not only increase the concentration of oxygen vacancies and broaden the light absorption range of zinc oxide without changing the crystal form of ZnO but also make it have the characteristics of preferential adsorption and degradation of CIP during the degradation process. Under the synergistic effect of CQDs, oxygen vacancies, and molecularly imprinted cavities, the molecularly imprinted material exhibits excellent photocatalytic and selective adsorption performance.

Integrated post-acquisition data processing strategy for rapid steroid sulfate characterization in Toad gall-bladder

LC–MS serves as a workhorse for chemical profile characterization of Chinese medicinal materials (CMMs) attributing to the ability of measuring fruitful MS/MS spectral information. However, it is laborious to extract the information belonging to the compounds-of-interest from the massive data matrixes even employing those well-defined post-acquisition data processing strategies. Here, efforts were devoted to propose an integrated strategy allowing rapid chemical homologs-focused data filtering through integrating the fit-for-purpose existing strategies, such as molecular weight imprinting (MWI), diagnostic fragment ion filtering (DFIF), neutral loss filtering (NLF), and isotope pattern filtering (IPF). Homologs-focused chemical characterization of a precious CMM namely Toad gall-bladder (Chinese name: Chandan) that is rich of diverse effective steroid sulfates, particularly bufogenin sulfates, bile acid sulfates and bilichol sulfates, was employed as a proof-of-concept. Recombinant human SULT2A1-catalyzed in vitro metabolism was undertaken to generate eight bufogenin sulfates to facilitate summarizing MS/MS spectral behaviors. After in-house data library construction and MS1 and MS2 spectral acquisition, data filtering was conducted as follows: 1) MWI and IPF was utilized in combination to capture deprotonated molecular ions and the 34S isotopic ions for the sulfates of those reported steroids; 2) m/z 79.9568 (SO3−·) and 96.9596 (HSO4−) were applied to DFIF; and 3) SO3 (79.9568 Da) served as the feature to achieve NLF. Those captured MS/MS information subsequently participated in tentatively structural annotation through applying those empirical mass fragmentation rules. As a result, 71 compounds including 7 bufogenin sulfates, 17 bile acid sulfates, 13 bilichol sulfates and a C-23 steroid sulfate were detected from Toad gall-bladder and thereof, 39 ones received plausible identities assignment. Above all, the steroid sulfates in Toad gall-bladder were profiled in depth, and more importantly, the proposed strategy should be a meaningful option for, but not limited to, submetabolome characterization in CMMs.

Construction of a molecularly imprinted fluorescent sensor based on an amphiphilic block copolymer-metal-organic framework for the detection of oxytetracycline in milk.

A metal-organic framework (MOF) is a good carrier for molecular imprinting due to its high surface area and strong adsorption capacity, but its poor dispersibility in aqueous solution is one of the significant drawbacks, which can severely impede its effectiveness. Amphiphilic block copolymers are good hydrophilic materials and have the potential to overcome the shortcomings of MOFs. In order to improve the hydrophilicity of molecularly imprinted fluorescent materials, we have applied a combination of molecularly imprinted technology and amphiphilic block copolymers on MOFs for the first time. Amphiphilic PAVE copolymer is selected as the molecular imprinted functional monomer to improve the hydrophilicity of UiO-66-NH2. The synthesized PAVE-MOF-MIP has adequate water dispersion ability and fluorescence activity. When encountering oxytetracycline, PAVE-MOF-MIP will produce fluorescence quenching, it is used to construct a fluorescence detection platform for oxytetracycline detection. Compared with traditional MIP@MOF, PAVE-MOF-MIP has better water dispersion ability and detection accuracy. Under optimal conditions, the linear range of oxytetracycline detection is 10-100 μmol L-1, and the minimum limit of detection (LOD) is 86 nmol L-1. This paper proposes a novel approach to use amphiphilic block copolymers as molecularly imprinted monomers on MOFs, providing an innovative idea that has not been previously explored.

Using Quercetin to Construct Molecularly Imprinting Polymer in the Preparation and Enrichment of Flavonol and Flavonoid Compounds.

Flavonol and flavonoid compounds are important natural compounds with various biomedical activities. Therefore, it is of great significance to develop a strategy for the specific extraction of flavonol and flavonoid compounds. Quercetin is a well-studied flavonoid possessing many health benefits. This compound is a versatile antioxidant known to possess protective abilities against body tissue injury induced by pathological situations and various drug toxicities. Although quercetin is widely distributed in many plants, its content generally is not very high. Therefore, the specific extraction of quercetin as well as other flavonol and flavonoid compounds has profound significance. In this work, the quercetin molecularly imprinting polymer (QMIP) was successfully prepared, in which a typical flavonol quercetin was selected as the template molecule. QMIP was synthesized by performing the surface molecular imprinting technology on the surface of NH2-MIL-101(Fe). Our study results showed that QMIP exhibited quick binding kinetic behavior, a high adsorption capacity (57.04[Formula: see text]mg/g), and the specific recognition ability toward quercetin compared with structurally distinct compounds (selective [Formula: see text]). The specific adsorption ability of quercetin by QMIP was further explained using computation simulation that molecules with non-planar 3D conformations hardly entered the molecularly imprinted cavities on QMIP. Finally, QMIP was successfully used for the specific extraction of quercetin and five other flavonol and flavonoid compounds in the crude extracts from Sapium sebiferum. This study proposes a new strategy to synthesize the molecularly imprinted polymer based on a single template for enriching and loading a certain class of active ingredients with similar core structures from variable botanicals.

Multifunctional molecularly imprinted nanozymes with improved enrichment and specificity for organic and inorganic trace compounds.

Although nanozymes exhibit properties superior to those of natural enzymes and conventional engineered enzymes, the development of highly specific nanozymes remains a challenge. New yolk-shell Fe3O4 molecularly imprinted (MIP@void@Fe3O4) nanozymes with peroxidase-like activity were developed by modelling the substrate channels of natural enzymes through molecular imprinting techniques and interfacial affinity modifications in this study. To establish a platform technology for the adsorption and determination of inorganic and organic contaminants, lead ion (Pb2+) and diazinon (DIZ), respectively, were selected as imprinting templates, and a hollow mesoporous shell was synthesized. The as-prepared MIP@void@Fe3O4 nanozymes, characterized using TEM, HRTEM, SEM, FT-IR, TGA, VSM and XPS, not only affirmed the successful fabrication of a magnetic nanoparticle with a unique hollow core-shell structure but also facilitated an exploration of the interfacial bonding mechanisms between Fe3O4 and other shell layers. The enrichment of the MIP@void@Fe3O4 nanozymes due to imprinting was approximately 5 times higher than the local substrate concentration and contributed to the increased activity. Based on selective and competitive recognition experiments, the synthesized nanozymes could selectively recognize organic and inorganic targets with the lowest detection limits (LOD) of 6.6 × 10-9 ppm for Pb2+ and 5.13 × 10-11 M for DIZ. Therefore, the proposed biosensor is expected to be a potent tool for trace pollutant detection, which provides a rational design for more advanced and subtle methods to bridge the activity gap between natural enzymes and nanozymes.

Recent advances in nonenzymatic electrochemical biosensors for sports biomarkers: focusing on antibodies, aptamers and molecularly imprinted polymers.

Nonenzymatic electrochemical biosensors, renowned for their high sensitivity, multi-target analysis capabilities, and miniaturized integration, align well with the requirements of non-invasive, multi-index integrated, continuous monitoring, and user-friendly wearable biosensors in sports science. In the past three years, novel strategies targeting specific responses to sports biomarkers have opened new avenues for applications in sports science. However, these advancements also pose challenges in achieving adequate sensitivity and specificity for online analysis of complex sweat bio-samples. Our article focuses on three key nonenzymatic electrochemical biosensing strategies: antigen-antibody reactions, nucleic acid aptamer recognition, and molecular imprinting capture. We delve into strategies to enhance specificity and sensitivity in the application of biosensors in sports science, including shortening signal transduction paths through built-in signal probes, increasing reaction sites through increased surface area and the introduction of nanostructures, multi-target analyses, and microfluidic techniques.