Magnetic Molecularly Imprinted Polymers Research Articles

High Mannose-Specific Aptamers for Broad-Spectrum Virus Inhibition and Cancer Targeting

High Mannose-Specific Aptamers for Broad-Spectrum Virus Inhibition and Cancer Targeting

Magnetic Molecularly Imprinted Polymers: An Update on Their Use in the Separation of Active Compounds from Natural Products.

During the last few years, separation techniques using molecularly imprinted polymers (MIPs) have been developed, making breakthroughs using magnetic properties. Compared to conventional MIPs, magnetic molecularly imprinted polymers (MMIPs) have advantages in sample pretreatment due to their high specificity and selectivity towards analytes as a result of their larger specific surface areas and highly accessible specific binding sites. The techniques of isolation of active compounds from natural products usually require very long process times and low compound yields. When MMIPs are used in sample separation as Solid Phase Extraction (SPE) sorbents, the MMIPs are introduced into the dissolved sample and spread evenly, and they form bonds between the analyte and the MMIPs, which are then separated from the sample matrix using an external magnetic field. This process of separating analytes from the sample matrix makes the separation technique with MMIPs very simple and easy. This review discusses how to synthesize MMIPs, which factors must be considered in their synthesis, and their application in the separation of active compounds from natural products. MMIPs with magnetic core-shells made by co-precipitation can be a good choice for further development due to the high synthesis yield. Further optimization of the factors affecting the size and distribution of magnetic core-shell particles can obtain higher synthesis yields of MMIPs with higher adsorption capacity and selectivity. Thus, they can isolate target compounds from natural plants in high yields and purity.

Design and synthesis of Fe3O4@Au@cyclodextrin-molecularly imprinted polymers labeled with SERS nanotags for ultrasensitive detection of transferrin

As an important clinical biomarker, transferrin (TRF) plays an indispensable role in the function regulation of human body and its concentration reflects the occurrence of some diseases. Herein, a sensor based on magnetic molecularly imprinted polymers (MMIPs) and surface-enhanced Raman scattering (SERS) was developed for the sensitive detection of TRF. For this purpose, Fe3O4@Au@cyclodextrin-MIPs were successfully synthesized using β-cyclodextrin as the functional monomer because its appropriate size, hydrophobic cavities, and hydroxyl groups benefitted anchoring TRF through noncovalent interactions. An appropriate hydrophilic imprinted layer was generated by self-copolymerization of dopamine and m-aminophenylboronic acid (APBA). After TRF was captured by Fe3O4@Au@cyclodextrin-MIPs, it was labeled with 4-mercaptophenylboronic acid-modified AgNPs as SERS nanotags to construct a sandwich structured sensor. This MMIP-SERS sensor behaved excellent identification and detection performances toward TRF since Fe3O4@Au@cyclodextrin-MIPs contributed to high specificity of the assay and SERS provided high sensitivity. Furthermore, the reliability and feasibility of the sensor in real serum samples were verified by determining TRF from liver disease patients, suggesting its great potential in clinical TRF detection.

A novel magnetic molecularly imprinted polymer for selective extraction and determination of quercetin in plant samples

Molecularly imprinted polymers that mimic the binding mechanism of antibodies and their antigens exhibit several advantages, such as fast synthesis, low cost, high stability, and allow to overcome the ethical issues associated with antibody farming in animals. Herein, a novel strategy combining the magnetic molecularly imprinted polymer (MMIP) as an artificial antibody with a fluorescence procedure for the detection of quercetin in plant samples was designed. The MMIP was synthesized via a radical polymerization process to recognize specific functional groups of quercetin using a green technique based on high energy ultrasound irradiation. The developed MMIP was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, scanning/transmission electron microscopy, and thermal gravimetric analysis, which confirmed the successful preparation of MMIP. The adsorption capacity and selectivity of the MMIP for quercetin and other interferents analogous were performed. The MMIP was applied in the solid-phase extraction (SPE) technique as a selective sorbent for the sample preparation. Besides, a sensitive fluorometric method for the quantitation of quercetin was developed. A linear response was obtained within the concentration of 0.005–1.25 μg mL−1 of quercetin. The limit of detection and quantitation were 1.1 ng mL−1 and 3.7 ng mL−1, respectively. The average recoveries for quercetin were between 92.2% and 104.7% with an RSD less than 5.06% in spiked orange juice and tea extract samples. Furthermore, the developed procedure was successfully combined with a new paper-based analytical device for on-site smartphone analysis of quercetin.

Dual selective sensor for exosomes in serum using magnetic imprinted polymer isolation sandwiched with aptamer/graphene oxide based FRET fluorescent ignition

The selective and sensitive detection of cancerous exosomes in serum is critical for early disease diagnosis and improved prognosis. Previous exosome-related research has been limited by a lack of well-understanding in exosomes as well as the challenging background interference of body fluid. Molecularly imprinted polymers (MIPs) and nucleic acid aptamers can be regarded as the two alternatives to antibodies. When using imprinted polymer technology, comprehensive and precise information about the target constituents is not required. In this study, a novel kind of dual selective fluorescent nanosensor for the poorly characterized exosomes was constructed by integrating magnetic MIP selective exosome capture sandwiched with an aptamer/graphene oxide fluorescence resonance energy transfer system (FRET) based selective ‘turn-on’ exosome labeling heterogeneously. The overall strategy performance was successively evaluated using lysozyme and exosomes as targets. Good linearity and high sensitivity achieved were demonstrated. The LOD of exosomal detection in serum was 2.43 × 106 particles/mL, lower than other immunology based detection methods. The discrimination between serum from breast cancer patients and healthy people was also primarily studied. In conclusion, the developed sensor with outstanding selectivity, high detection sensitivity, simplicity, low cost, and wide applicability for known or unknown targets present significant potential in challenging clinical diagnosis.

Copper mediated molecularly imprinted polymers for fast recognizing tylosin

As one kind of artificial antibody, molecularly imprinted polymers (MIPs) has been widely used to separate/enrich target molecules from samples with the complex matrix prior to instrumental analysis. In this work, one novel copper mediated magnetic MIPs was developed towards anti-bacteria macrolide antibiotic tylosin (TYL). The obtained microspheres had a lot of convexities distributed evenly on the surface. And it exhibited high hydrophilicity and superparamagnetic ability, as well as excellent selectivity and specificity. Notably, it only took 5 min to reach the absorption equilibrium for TYL, which made it highly feasible for high-throughput analysis. Furthermore, the microspheres was applied as the magnetic dispersed solid phase extraction material to enrich trace TYL residue in (spiked) human urine. At three spiking levels, mean recoveries are in the range of 76.42–93.72% with relative standard deviations of 2.75–8.24% (n = 3) with HPLC/UV-Vis. The work provided one promising reference to prepare novel solid phase extraction materials for enriching/separating trace component in complex matrix.

Removal of phthalate ester compound from PVC plastic samples using magnetic molecularly imprinted polymer on the surface of superparamagnetic Fe3O4 (Fe3O4@MIPs)

In this study, novel magnetic molecularly imprinted polymers (MMIPs) were successfully synthesized for selective separation of di(2-ethylhexyl)phthalate (DEHP) in PVC sample solutions. Polymerization was carried out using Fe3O4 modified by oleic acid, ethylene glycol dimethacrylate (EGDMA), methacrylic acid (MAA), and benzoyl peroxide (BPO) in the presence of DEHP as template molecule to produce MMIPs named Fe3O4@MIPs. Magnetic non-molecularly imprinted polymers (MNIPs) were also prepared for comparison purposes. The structure and physical properties of MMIPs and MNIPs were characterized using FT-IR, SEM, TEM, VSM and zeta potential analysis. The FT-IR spectra showed that MMIPs were successfully synthesized, indicated by the presence of a Fe-O peak at 586 cm−1, a benzene derivative peaks at 709, 1072, and 1155 cm−1, a carbonyl peak of MAA at 1728 cm−1 and a C–H peak of oleic acid at 2954 cm−1. SEM and TEM measurements showed that MMIPs were porous polymers with a smaller particle size than MNIPs. VSM measurement showed that MMIPs were superparamagnetic with a saturation magnetism value of 39.92 emu/g. MMIPs have a better adsorption capacity than MNIPs with an imprinting factor (IF) value of 3.37 and a maximum adsorption capacity value of 17.21 mg/g. The sorption studies showed that the adsorption process followed the Langmuir isotherm model and fitted well to a pseudo-second-order kinetic model with ΔHo of −82.17 kJ mol−1. Moreover, MMIPs were more selective to DEHP than dibutyl phthalate (DBP), with a selectivity coefficient value of 4.57. The desorption test showed that MMIPs showed good regeneration with a desorption percentage of 98.42% and decreasing in adsorption capacity of 11.2% after three times regenerations. DEHP removal from PVC samples using MMIP showed that polymer could reduce the matrixes effect with a recovery percentage of around 91.03–99.68%.

Magnetic Molecularly Imprinted Polymer (MMIP) Mediated Bacterial Esterase-Based Assay for Captan Detection in Milk

Magnetic Molecularly Imprinted Polymer (MMIP) Mediated Bacterial Esterase-Based Assay for Captan Detection in Milk

Influence of hydrophilic and hydrophobic functional monomers on the performance of magnetic molecularly imprinted polymers for selective recognition of human insulin

Magnetic molecularly imprinted polymers (MMIPs) were used to detect and bioseparation of insulin. Because of the significant role of electrostatic interactions, the effects of hydrophilic/hydrophobic interactions were investigated in non-covalent molecular imprinting. The imprinting polymer was synthesized using different type and molar ratios of functional monomers containing acrylamide (AAm) as the neutral-hydrophilic monomer alongside methacrylic acid (MAA) and 2-dimethyl aminoethyl methacrylate (DMA) in the two cases: hydrophilic-hydrophobic-neutral (MMIP3) and hydrophobic-neutral (MMIP2), respectively. The MMIPs adsorption results showed high capacity, good selectivity, and high rapidness to insulin adsorption in both cases. The maximum adsorption (Q) and imprinting factor (IF) of MMIP2 and MMIP3 obtained 54 mg.g−1 and 4.4, and 67 mg.g−1 and 3.2, respectively. In addition, dynamic light scattering results revealed that the average particle size of the surface-modified magnetic nanoparticles (Fe3O4@SiO2@MPS), MMIP2, and MMIP3 were equal to 135 ± 8, 360 ± 21, and 275 ± 28 nm, respectively. The thermogravimetric analysis demonstrated that MNIP2 has almost 25% more polymer layer than MNIP3. VSM analysis was also carried out showed the magnetic power of 21.88, 7.74, and 19.93 emu/g for MNPs, MMIP2, and MMIP3, respectively.

Selective Recognition of Gallic Acid Using Hollow Magnetic Molecularly Imprinted Polymers with Double Imprinting Surfaces.

Gallic acid is widely used in the field of food and medicine due to its diversified bioactivities. The extraction method with higher specificity and efficiency is the key to separate and purify gallic acid from complex biological matrix. Herein, using self-made core-shell magnetic molecularly imprinted polymers (MMIP) with gallic acid as template, a hollow magnetic molecularly imprinted polymer (HMMIP) with double imprinting/adsorption surfaces was prepared by etching the mesoporous silica intermediate layer of MMIP. The characterization and adsorption research showed that the HMMIP had larger specific surface area, higher magnetic response strength and a more stable structure, and the selectivity and saturated adsorption capacity (2.815 mmol/g at 318 K) of gallic acid on HMMIP were better than those of MMIP. Thus, in addition to MMIP, the improved HMMIP had excellent separation and purification ability to selectively extract gallic acid from complex matrix with higher specificity and efficiency.

Enhancement of Electrochemical Detection of Gluten with Surface Modification Based on Molecularly Imprinted Polymers Combined with Superparamagnetic Iron Oxide Nanoparticles.

Novel molecularly imprinted polymers (MIPs) represent a selectively recognized technique for electrochemical detection design. This rapid and simple method prepared via chemical synthesis consists of a monomer crosslinked with an initiator, whereas low sensitivity remains a drawback. Nanomaterials can improve charge transfer for MIP surface modification in order to overcome this problem. SPIONs have semiconductor and superparamagnetic properties that can enhance carrier mobility, causing high sensitivity of electrochemical detection. In this work, surface modification was achieved with a combination of MIP and SPIONs for gluten detection. The SPIONs were synthesized via the chemical co-precipitation method and mixed with MIPs by polymerizing gluten and methyl methacrylate (MMA), presented as a template and a monomer. Magnetic MIP (MMIP) was modified on a carbon-plate electrode. The morphology of modified electrode surfaces was determined by scanning electron microscopy–energy-dispersive X-ray spectrometry. The performance of the MMIP electrode was confirmed by cyclic voltammetry, amperometry, and electrochemical impedance spectroscopy. The MMIP electrode for gluten detection shows a dynamic linear range of 5–50 ppm, with a correlation coefficient of 0.994 and a low detection limit of 1.50 ppm, which is less than the U.S. Food and Drug Administration requirements (20 ppm); moreover, it exhibits excellent selectivity, sensitivity, stability, and reproducibility.

Computational approach and ultrasound Probe–Assisted synthesis of magnetic molecularly imprinted polymer for the electrochemical detection of bisphenol A

A new theoretical approach based on density functional theory was developed to find the most suitable monomer and porogen solvent to design a specific molecularly imprinted polymer (MIP) for bisphenol-A (BPA). Various theoretical investigations were carried out including HOMO and LUMO calculation, molecular electrostatic potential of the BPA-monomer interactions, and selection of the optimal monomer and porogen solvent using binding energies of BPA-monomer. Besides, counterpoise correction was used to avoid the problem of basis set superposition error. The theoretical results demonstrated that among virtual monomers, methacrylic acid and acrylamide showed good affinity towards BPA. The optimization of solvents was done using the polarizable continuum model and it was found that acetone was the most appropriate solvent. According to the obtained theoretical approach results, magnetic MIP (magMIP) was prepared using a high-power ultrasound probe. Scanning/transmission electron microscopy, thermogravimetric analysis, Fourier-transform infrared spectroscopy, and X-ray diffraction were used to characterize the as-prepared magMIP. Adsorption behavior was explained by Sips and pseudo-second-order models for isotherm and kinetic studies, respectively. Furthermore, magMIP showed favorable adsorption selectivity for BPA over other phenolic compounds. Finally, the developed magMIP was successfully used as a sorbent in solid-phase extraction combined with an electrochemical sensor for the detection of BPA. The obtained limit of detection was 66 nM and the recovery values in tap water sample were 104 and 105.5% for 2 and 10 µM, respectively, with RSD values lower than 5 % (n = 3).

Design and synthesis of a new magnetic molecularly imprinted polymer nanocomposite for specific adsorption and separation of diazinon insecticides from aqueous media

Today, molecularly imprinted polymers have received much engrossment as selective adsorbents and substrates. In the present study, a magnetic molecularly imprinted polymer (MIP) based on clay, graphene oxide and polydopamine was synthesized and used for adsorption and specific entrapment of Diazinon pesticide. The magnetic MIP nanocomposite was characterized by XRD, FT-IR, SEM, VSM, and AFM methods. The response surface method (RSM) was used to optimize and modeling the effective parameters of the adsorption of Diazinon by this polymer, and the results were compared with an artificial neural network (ANN). The results showed magnetic saturation of GO/Clay/Fe3O4@PDA MIP nanocomposite is equal to 8.28 emu/g, average particle size, average surface roughness and imprinting factor of this polymer are equal to 105 nm, 66.72 nm and 2.35, respectively. This polymer has a very selective ability to adsorption of Diazinon by removal percentage equal to 99.85 at pH = 7, the concentration of Diazinon = 1.45 ppm, the dosage of polymer = 1.24 g/L, time = 16 min. Also, the RSM results showed that the model included the effect of parameters on the absorption efficiency is a quadratic polynomial equation with the coefficient of determination equal to 0.98% and the most effective parameter on removal percentage is the dosage of the polymer. The artificial neural network with 11 neurons in the hidden layer with the coefficient of determination of 0.96% was also suitable for modeling the absorption process. Compared to the ANN model, the RSM model has better capability and lower error values. Freundlich isothermal models and pseudo-second-order and Elovich kinetic models in different concentrations of Diazinon were appropriate for explanation the adsorption process. The mechanism of Diazinon adsorption by MIP nanocomposite was influenced by intraparticle and extraparticle diffusion. Also, GO/Clay/Fe3O4@PDA MIP nanocomposite has an adsorption capacity of more than 98% up to nine cycles of the adsorption/desorption process.

Analysis of heterocyclic aromatic amines using selective extraction by magnetic molecularly imprinted polymers coupled with liquid chromatography - Mass spectrometry.

Heterocyclic aromatic amines (HCAs) are highly carcinogenic and mutagenic chemicals. This study reports on the development of magnetic molecularly imprinted polymers (MMIPs) for the purification and quantification of HCAs. A novel magnetic molecularly imprinted polymer was successfully prepared using a surface molecular imprinting method using functionalized Fe particles as the magnetic cores. 2-Amino-3-methylimidazo[4,5-f]quinoline (IQ) was used as a molecular template; methacrylic acid (MAA), ethylene glycol dimethyl acrylate (EGDMA), 2, 2'-Azobis (2-methylpropionitrile) were used as the functional monomer, crosslinker, and initiator, respectively. The use of the template/functional monomer/crosslinking agent at a ratio of 1:4:20 resulted in a product with better adsorption properties (3.24 mg/g). The HCAs were successfully detected and quantified in processed meat samples by MISPE and LC-MS/MS. Under the final optimized detection conditions, the proposed method offered good linearity (R > 0.995) for the five HCAs with an acceptable level of precision, and an LOQ of 0.05 ng/g was successfully achieved.

Photocatalytic degradation of norfloxacin by magnetic molecularly imprinted polymers: influencing factors and mechanisms

ABSTRACT Novel magnetic molecularly imprinted polymers (MMIP) were prepared for selective removal of norfloxacin by effectively utilizing photocatalytic degradation and magnetic separation techniques. The imprinted material with titanium layer and multihole surface showed an excellent photocatalytic property. In this paper, the kinetics of photocatalytic degradation of norfloxacin by MMIP was explored, and the influences of environmental factors, including solution pH, humic acid, common ions and water media on photocatalytic performance of MMIP were elucidated. The results showed that MMIP had good adaptability and could degrade norfloxacin within 60 min, but the degradation rate constant decreased in surface water. Based on the identification of intermediate products, the possible degradation pathways of norfloxacin were analysed, speculating that it might be degraded into small molecules in the form of de-piperazine ring, de-carboxyl group and de-fluorine. Moreover, the mineralization ratio of norfloxacin could reach 84.2% after ultraviolet irradiation for 150 min, and the low cobalt release of MMIP enhanced the security of the material. The results of adsorption and degradation cycle tests showed that MMIP obtained by molecular imprinting technology had excellent performance in sustainable use for micro organic pollutants removal.

Magnetic molecularly imprinted polymer for the simultaneous selective extraction of phenoxy acid herbicides from environmental water samples

A selective magnetic molecularly imprinted polymer (MMIP) was synthetized with 4-chloro-2-methylphenoxyacetic acid as template and 4-vinylpiridine as monomer in presence of vinylized magnetite nanoparticles. Scanning electron microscopy, nitrogen adsorption-desorption isotherms, Fourier transform infrared spectrometry and vibrating sample magnetometry were applied to characterize the resulting material. The synthesized MMIP was applied as sorbent in magnetic molecularly imprinted solid-phase extraction (MMISPE) for selective extraction of a mixture of the five herbicides 4-chloro-2-methylphenoxyacetic acid (MCPA), 4-(4-chloro-2-methylphenoxy)butyric acid (MCPB), mecoprop (MCPP), fenoxaprop (FEN) and haloxyfop (HAL). Several parameters affecting the extraction conditions were optimized to achieve the best extraction performance. The best MMISPE combined with HPLC-DAD gave detection and quantification limits between 0.33 and 0.71 μg L−1 and 1.1–2.4 μg L−1, respectively, were obtained. The precision of the whole method provided RSD values below 7.3%, and the accuracy was demonstrated by the analysis of several water samples of different origins, with recoveries ranged from 77 to 98%. Moreover, a remarkable re-usability of the MMIP sorbent, more than 65 uses without losses in extraction capacity, was obtained.

SERS-based boronate affinity biosensor with biomimetic specificity and versatility: Surface-imprinted magnetic polymers as recognition elements to detect glycoproteins

Glycoproteins are a class of proteins with significant biological functions and clinical implications. Due to glycoproteins’ reliability for the quantitative analysis, they have been used as biomarkers and therapeutic targets for disease diagnosis. We propose a sandwich structure-based boronate affinity biosensor that can separate and detect target glycoproteins by magnetic separation and Surface-enhanced Raman scattering (SERS) probes. The biosensor relies on boronic acid affinity magnetic molecularly imprinted polymer (MMIPs) with pH response as "capturing probe" for glycoproteins, and Au-MPBA@Ag modified with 4-mercaptophenylboronic acid (MPBA) as SERS probes, among which, MPBA has both strong SERS activity and can specifically recognize and bind to glycoproteins. MMIPs ensured specific and rapid analysis, and SERS detection provided high sensitivity. The proposed boronate affinity SERS strategy exhibited universal applicability and provided high sensitivity with limit of detection of 0.053 ng/mL and 0.078 ng/mL for horseradish peroxidase and acid phosphatase, respectively. Ultimately, the boronate affinity SERS strategy was successfully applied in detection of glycoprotein in spiked serum sample with recovery between 90.6% and 103.4%, respectively. In addition, this study used a portable Raman meter, which can meet the requirements of point-of-care testing. The biosensor presented here also has advantages in terms of cost-effectiveness, stability, and detection speed.

Development and Characterization of Magnetic SARS-CoV-2 Peptide-Imprinted Polymers.

The development of new methods for the rapid, sensitive, and selective detection of SARS-CoV-2 is a key factor in overcoming the global pandemic that we have been facing for over a year. In this work, we focused on the preparation of magnetic molecularly imprinted polymers (MMIPs) based on the self-polymerization of dopamine at the surface of magnetic nanoparticles (MNPs). Instead of using the whole SARS-CoV-2 virion as a template, a peptide of the viral spike protein, which is present at the viral surface, was innovatively used for the imprinting step. Thus, problems associated with the infectious nature of the virus along with its potential instability when used as a template and under the polymerization conditions were avoided. Dopamine was selected as a functional monomer following a rational computational screening approach that revealed not only a high binding energy of the dopamine–peptide complex but also multi-point interactions across the entire peptide template surface as opposed to other monomers with similar binding affinity. Moreover, variables affecting the imprinting efficiency including polymerization time and amount of peptide and dopamine were experimentally evaluated. Finally, the selectivity of the prepared MMIPs vs. other peptide sequences (i.e., from Zika virus) was evaluated, demonstrating that the developed MMIPs were only specific for the target SARS-CoV-2 peptide.

Facile fabrication of surface molecularly imprinted magnetic polydopamine for selective adsorption of fluoroquinolone from aqueous solutions

To address problems such as environmental accumulation, improved methods are required for the detection and analysis of fluoroquinolones. Herein, we prepared a surface molecularly imprinted polymer (MIP) based on dopamine-coated magnetic nanoparticles. The performance of this MIP as a novel adsorbent for fluoroquinolones was analyzed using high-performance liquid chromatography. Furthermore, the morphology and physicochemical properties of the prepared material were characterized by Fourier transform infrared spectroscopy, transmission electron microscopy, thermogravimetric analysis, Brunauer–Emmett–Teller surface area analysis, and vibrating sample magnetometry. The synthesized molecules consisted of a core–shell constitution with a Fe3O4 nucleus and a polydopamine enclosure, the surface of which was imprinted using gatifloxacin as a template molecule. The obtained polymers had a high specific surface area, good superparamagnetism, and excellent selectivity of the target molecules. Under optimal adsorption conditions, the ultimate loading capacity of gatifloxacin on the MIP was 51.9 mg/g, with an equilibrium adsorption time of 30 min and an imprinting factor of 2.24. After six cycles, the adsorption capacity of this adsorbent did not decrease significantly. For the analytical characteristics of the method, we inserted the application part of the sample in the local river water. Through the spiked recovery of the three FQs aqueous solutions, it was found that their spiked recovery, LOD, and LOQ were 84.1–91.9%, 6.4–9.9 ng mL−1, and 17.8–34.5 ng mL−1, respectively. Owing to its adsorption selectivity and recyclability, this magnetic MIP is a promising adsorbent for sample separation and pretreatment applications.

Multi-functional magnetic molecular imprinting probe for visual detection of IgY antibodies.

Egg yolk antibodies (IgY)are analternative to mammalian antibodies, which have been successfully applied in treatment ofdisease, asimmunochemical reagents and asfood additives. A fast, accurate, and easy-to-operate detection method for IgY antibodies is needed. Herein, we developed a rapid and cost-effective colorimetric assay for the ultrasensitive detection of anti-S. aureus IgY antibodies using multi-functional magnetic molecularly imprinted polymers (MMIPs). The prepared MMIPs can recognize, adsorb, and separate the analyte from the matrix efficiently, and oxidize TMB to generate a colorimetric signal within ~ 60min. As low as 0.013mg·mL-1 was able to be detected by using this method. The visual detection limit reached 0.02mg·mL-1. By testing the IgY in milk samples, the feasibility was verified.