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1.
Mikrochim Acta ; 191(5): 247, 2024 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587580

RESUMO

Alumina inorganic molecularly imprinted polymer (MIP) modified multi-walled carbon nanotubes (MWCNTs) on a glassy carbon electrode (MWCNTs-Al2O3-MIP/GCE) was firstly designed and fabricated by one-step electro deposition technique for the detection of uric acid (UA) in sweat. The UA templates were embedded within the inorganic MIP by co-deposition with Al2O3. Through the evaluation of morphology and structure by Field Emission Scanning Electron Microscope (SEM), Energy Dispersive X-ray Spectroscopy (EDS), X-ray Photoelectron Spectroscopy (XPS) and Transmission Electron Microscopy (TEM), it was verified that the specific recognition sites can be fabricated in the electrodeposited Al2O3 molecular imprinted layer. Due to the high selectivity of molecular imprinting holes, the MWCNTs-Al2O3-MIP/GCE electrode demonstrated an impressive imprinting factor of approximately 2.338 compared to the non-molecularly imprinted glassy carbon electrode (MWCNTs-Al2O3-NIP/GCE) toward uric acid detection. Moreover, it exhibited a remarkable limit of detection (LOD) of 50 nM for UA with wide detection range from 50 nM to 600 µM. The MWCNTs-Al2O3-MIP/GCE electrode also showed strong interference resistance against common substances found in sweat. These results highlight the excellent interference resistance and selectivity of MWCNTs-Al2O3-MIP/GCE sensor, positioning it as a novel sensing platform for non-invasive uric acid detection in human sweat.


Assuntos
Nanotubos de Carbono , Fosfatos , Suor , Humanos , Polímeros Molecularmente Impressos , Ácido Úrico , Óxido de Alumínio
2.
Analyst ; 149(11): 3161-3168, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38632945

RESUMO

This article presents the development of a distance-based thread analytical device (dTAD) integrated with an ion-imprinted polymer (IIP) for quantitative monitoring of zinc ions (Zn2+) in human urine samples. The IIP was easily chemically modified onto the thread channel using dithizone (DTZ) as a ligand to bind to Zn2+ with methacrylic acid (MAA) as a functional monomer and ethylene glycol dimethacrylate (EGDMA) as well as 2,2-azobisisobutyronitrile (AIBN) as cross-linking agents to enhance the selectivity for Zn2+ detection. The imprinted polymer was characterized using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy and Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy (SEM-EDS). Under optimization, the linear detection range was from 1.0 to 20.0 mg L-1 (R2 = 0.9992) with a limit of detection (LOD) of 1.0 mg L-1. Other potentially interfering metal ions and molecules did not interfere with this approach, leading to high selectivity. Furthermore, our technique exhibits a remarkable recovery ranging from 100.48% to 103.16%, with the highest relative standard deviation (% RSD) of 5.44% for monitoring Zn2+ in human control urine samples, indicating high accuracy and precision. Similarly, there is no significant statistical difference between the results obtained using our method and standards on zinc supplement sample labels. The proposed method offers several advantages in detecting trace Zn2+ for point-of-care (POC) medical diagnostics and environmental sample analysis, such as ease of use, instrument-free readout, and cost efficiency. Overall, our developed dTAD-based IIP method holds potential for simple, affordable, and rapid detection of Zn2+ levels and can be applied to other metal ions' analysis.


Assuntos
Limite de Detecção , Zinco , Humanos , Zinco/química , Zinco/urina , Impressão Molecular/métodos , Polímeros/química , Polímeros Molecularmente Impressos/química
3.
Anal Methods ; 16(18): 2878-2887, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38639924

RESUMO

Shikimic acid (SA) is one of the most effective drugs against the A (H1N1) virus and has high medicinal value. Additionally, it has the ability to generate non-toxic herbicides and antimicrobial medications. The extraction from plants has proven to be the main route of production of SA with economic benefits and environmental efficiency. Therefore, it is necessary to perform purification of SA from these herbal medicines before quantifying it. In this study, researchers employed a boronate affinity-based controlled oriented surface imprinting technique to produce molecularly imprinted polymers (MIPs) as highly effective solid phase extraction (SPE) adsorbents for the isolation and purification of SA. 3-Fluoro-4-formylphenylboronic acid functionalized silica nanoparticles were used as supporting materials for immobilizing SA. Poly(2-anilinoethanol) with a higher hydrophilic domain can be used as an effective imprinting coating. The prepared SA-imprinted silica nanoparticles exhibited several significant results, such as good specificity, high binding capacity (39.06 ± 2.24 mg g-1), moderate binding constant (6.61 × 10-4 M-1), fast kinetics (8 min) and low binding pH (pH 5.0) toward SA. The replication of SA-imprinted silica nanoparticles was deemed satisfactory. The SA-imprinted silica nanoparticles could be still reused after seven adsorption-desorption cycles, which indicated high chemical stability. In addition, the recoveries of the proposed method for SA at three spiked level analysis in star aniseed and meadow cranesbill were 96.2% to 109.0% and 91.6% to 103.5%, respectively. The SA-imprinted silica nanoparticles that have been prepared are capable of identifying the target SA in real herbal medicines. Our approach makes sample pre-preparation simple, fast, selective and efficient.


Assuntos
Ácidos Borônicos , Impressão Molecular , Nanopartículas , Ácido Chiquímico , Dióxido de Silício , Extração em Fase Sólida , Dióxido de Silício/química , Nanopartículas/química , Impressão Molecular/métodos , Ácido Chiquímico/química , Ácido Chiquímico/isolamento & purificação , Ácidos Borônicos/química , Extração em Fase Sólida/métodos , Polímeros Molecularmente Impressos/química , Adsorção , Medicina Herbária/métodos
4.
Talanta ; 273: 125883, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38521023

RESUMO

Quercetin (QUE) is a powerful antioxidant and one of the common phenolic compounds found in plants, vegetables, and fruits, which has shown many pharmacological activities. The complex nature of the matrix in which QUE is found and its importance and potential uses in diverse applications force the researchers to develop selective and sensitive sensors. In the present work, a novel molecularly imprinted polymer (MIP)-based electrochemical sensor was fabricated for the selective and sensitive determination of the QUE in plant extracts and food supplements. Tryptophan methacrylate (TrpMA) was chosen as the functional monomer, whereas the photopolymerization (PP) method was applied using a glassy carbon electrode (GCE). Electrochemical and morphological characterizations of the developed sensor (TrpMA@QUE/MIP-GCE) were performed using cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM). The linear range of the developed sensor was determined to be in the range of 1.0-25 pM, while the limit of detection (LOD) was calculated to be 0.235 pM. In conclusion, The TrpMA@QUE/MIP-GCE sensor might be classified as a promising platform for selective and sensitive determination of QUE not only in plant extracts but also in commercial food supplements because of its reliability, reproducibility, repeatability, stability, and fast response time.


Assuntos
Fragaria , Impressão Molecular , Rubus , Polímeros/química , Quercetina , Reprodutibilidade dos Testes , Metanol , Técnicas Eletroquímicas/métodos , Carbono/química , Limite de Detecção , Polímeros Molecularmente Impressos , Eletrodos , Extratos Vegetais
5.
Anal Methods ; 16(10): 1480-1488, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38372557

RESUMO

Rutin (RUT), a natural flavonoid with various beneficial pharmacological actions such as cardioprotective, antioxidant, anti-inflammatory, neuroprotective, etc., is found in the content of many plants that are consumed daily. Due to the healthful effects, RUT is also included in the composition of various herbal supplement samples. Therefore, it is highly important to develop a sensor with high selectivity and sensitivity to determine RUT in complex samples. In this study, it was aimed to take advantage of the cheap, easy, and sensitive nature of electrochemistry and, in addition, to improve the selectivity. For this purpose, the functional monomer selected in the fabricated molecularly imprinted polymer (MIP) was N-methacryloyl-L-aspartic acid (MA-Asp) while photopolymerization (PP) was applied as the polymerization route. After completing critical optimization steps, the developed sensor (MA-Asp@RUT/MIP-GCE) was characterized electrochemically and morphologically. As a result of analytical performance evaluation in standard solution, the linear response of the sensor was found in the concentration range between 1 and 10 pM with a detection limit of 0.269 pM. The recovery studies from plant extract and commercial herbal supplement samples emphasized accuracy and applicability. In imprinting factor studies figuring out quite good selectivity, molecules with a structure similar to RUT were selected as competitors to prove the affinity of the sensor against RUT. Consequently, the MA-Asp@RUT/MIP-GCE sensor offers a more sensitive and selective method thanks to its indirect analysis approach and also stands out with the diversity of its real sample application compared to other available studies.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Extratos Vegetais , Polímeros/química , Rutina , Técnicas Eletroquímicas/métodos , Impressão Molecular/métodos , Suplementos Nutricionais
6.
Zhongguo Zhong Yao Za Zhi ; 48(14): 3736-3742, 2023 Jul.
Artigo em Chinês | MEDLINE | ID: mdl-37475065

RESUMO

Molecularly imprinted polymers demonstrate outstanding performance in the research on trace ingredients because of their high selectivity. Stimuli-responsive molecularly imprinted polymers(STR-MIPs) with the introduction of different responsive groups on the basis of traditionally imprinted materials can undergo reversible transformations when exposed to external stimuli such as temperature, magnetism, pH or light. Such responsiveness, combined with the specific recognition, endows STR-MIPs with excellent perfor-mance in trace component studies. Traditional Chinese medicine(TCM) contains complex components with trace content, and thus STR-MIPs have broad application prospects in the enrichment analysis of trace components in TCM. This paper elaborates on the application of STR-MIPs in the enrichment analysis of trace components in TCM from the perspectives of different stimuli, summarized relevant research achievements in the recent five years to broaden the application fields of molecular imprinting, and proposed a few opi-nions about their future development.


Assuntos
Medicina Tradicional Chinesa , Impressão Molecular , Polímeros Molecularmente Impressos , Polímeros/química , Temperatura
7.
ACS Appl Mater Interfaces ; 15(21): 25898-25908, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37191997

RESUMO

The heat tolerance of tumor cells induced by heat shock proteins (HSPs) is the major factor that seriously hinders further application of PTT, as it can lead to tumor inflammation, invasion, and even recurrence. Therefore, new strategies to inhibit HSPs expression are essential to improve the antitumor efficacy of PTT. Here, we prepared a novel nanoparticle inhibitor by synthesizing molecularly imprinted polymers with a high imprinting factor (3.1) on the Prussian Blue surface (PB@MIP) for combined tumor starvation and photothermal therapy. Owing to using hexokinase (HK) epitopes as the template, the imprinted polymers could inhibit the catalytic activity of HK to interfere with glucose metabolism by specifically recognizing its active sites and then achieve starvation therapy by restricting ATP supply. Meanwhile, MIP-mediated starvation downregulated the ATP-dependent expression of HSPs and then sensitized tumors to hyperthermia, ultimately improving the therapeutic effect of PTT. As the inhibitory effect of PB@MIP on HK activity, more than 99% of the mice tumors were eliminated by starvation therapy and enhanced PTT.


Assuntos
Hipertermia Induzida , Impressão Molecular , Nanopartículas , Neoplasias , Animais , Camundongos , Polímeros Molecularmente Impressos , Terapia Fototérmica , Hexoquinase , Neoplasias/tratamento farmacológico , Nanopartículas/química , Trifosfato de Adenosina
8.
Food Chem ; 416: 135811, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-36898334

RESUMO

Substances that possess hierarchical and interconnected porous features are ideal choices for acting as skeletons to synthesize surface molecularly imprinted polymers (MIPs). In this work, rape pollen, a waste of biological resources, was calcined and a porous mesh material with a high specific surface area was obtained. The cellular material was adopted as a supporting skeleton to synthesize high-performance MIPs (CRPD-MIPs). The CRPD-MIPs presented an ultrathin imprinted layered structure, with an enhanced adsorption capacity for sinapic acid (154 mg g-1) relative to the non-imprinted polymers. The CRPD-MIPs also exhibited good selectivity (IF = 3.24) and a fast kinetic adsorption equilibrium (60 min). This method exhibited a good linear relationship (R2 = 0.9918) from 0.9440 to 29.26 µg mL-1, and the relative recoveries were 87.1-92.3%. The proposed CRPD-MIPs based on hierarchical and interconnected porous calcined rape pollen may be a valid program for the selective extraction of a particular ingredient from complicated actual samples.


Assuntos
Brassica napus , Impressão Molecular , Polímeros Molecularmente Impressos , Solventes Eutéticos Profundos , Extração em Fase Sólida/métodos , Adsorção , Extratos Vegetais , Solventes/química
9.
Talanta ; 257: 124394, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36858016

RESUMO

Early detection of breast cancer, the first main cause of death in women, with robust assay platforms using appropriate biomarkers is of great importance for diagnosis and follow-up of the disease progression. This paper introduces an extra selective and sensitive label-free aptasensor for the screening of BRCA1 gene biomarker by taking advantage of a gate modified with aptamer and molecularly imprinted polymer hybrid (MIP) as a new synthetic receptor film coupled with an electrolyte-gated molybdenum disulfide (MoS2) field-effect transistor (FET). The Au gate surface of FET was modified with insulin stabilized bimetallic Ag-Au@nanoclusters (Ag-Au@InsNCs), after which, the immobilization of the hybridized aptamer and o-phenylenediamine was electropolymerized to form an aptamer-MIP hybrid receptor. The output characteristics of Apta-MIP hybrid modified Au gate MoS2 FET device were followed as a result of change in electrical double layer capacitance of electrolye-gate interface. The magnitude of decrease in the drain current showed a linear response over a wide concentration range of 10 aM to 1 nM of BRCA1 ssDNA with a sensitivity as high as 0.4851 µA/decade of concentration and a limit of detection (LOD) of 3.0 aM while very low responses observed for non-imprinted polymer. The devised aptasensor not only was capable to the discrimination of the complementary versus one-base mismatch BRCA1 ssDNA sequence, but also it could detect the complementary BRCA1 ssDNA in spiked human serum samples over a wide concentration range of 10 aM to 1.0 nM with a low LOD of 6.4 aM and a high sensitivity 0.3718 µA/decade.


Assuntos
Técnicas Biossensoriais , Impressão Molecular , Feminino , Humanos , Proteína BRCA1 , Detecção Precoce de Câncer , Genes BRCA1 , Insulina , Polímeros Molecularmente Impressos , Molibdênio , Aptâmeros de Peptídeos/química
10.
Crit Rev Anal Chem ; 53(6): 1197-1208, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34908490

RESUMO

Membrane protected extraction is an ongoing innovation for isolation and pre-concentration of analytes from complex samples. The extraction process, clean-up and pre-concentration of analytes occur in a single step. The inclusion of solid sorbents such as molecularly imprinted polymers (MIPs) after membrane extraction ensures that selective double extraction occurs in a single step. The first step involves selective extraction using the membrane and diffused analytes are trapped on the solid sorbent enclosed in the membrane. No further clean-up is required even for very dirty samples like plant extracts and wastewaters samples. Sample clean-up occurs during extraction in the first process and not as additional step since matrix components are prevented from trapping on the sorbent. This can be referred to as prevention is better than cure approach. In this work, the analytical methods that employed membrane protected extraction for various organics such as pesticides, polycyclic aromatic hydrocarbons, and pharmaceuticals are reviewed. The designs of these analytical methods, their applications, advantages and drawbacks are discussed in this review. Literature suggests that the introduction of solid sorbents in membrane creates the much-needed synergy in selectivity. Previous reviews focused on membrane combinations with MIPs while discussing micro-solid-phase extraction. The scope of this review was broadened to include other sample preparation aspects such as membrane protected stir bar solvent extraction and membrane protected solid-phase microextraction. In addition, novel sample preparation methods for solid samples which include Soxhlet membrane protected molecular imprinted solid phase extraction and membrane protected ultra sound assisted extracted are discussed.


Assuntos
Praguicidas , Hidrocarbonetos Policíclicos Aromáticos , Extração em Fase Sólida/métodos , Microextração em Fase Sólida/métodos , Polímeros Molecularmente Impressos
11.
Molecules ; 27(20)2022 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-36296486

RESUMO

Alzheimer's disease is the most common neurodegenerative disease, characterized by memory loss and cognitive dysfunction. Raspberry fruits contain polyphenols which have antioxidant and anti-inflammatory properties. In this study, we used molecular imprinting technology to efficiently isolate phenolic components from the raspberry ethyl acetate extracts. Six phenolic components (ellagic acid, tiliroside, kaempferol-3-o-rutoside, gallic acid, ferulic acid and vanillic acid) were identified by UPLC-Q-TOF-MS analysis. Molecular docking was used to predict the anti-inflammatory effects and anti-Alzheimer's potential of these isolated compounds, which showed a good binding ability to diseases and related proteins. However, the binding energy and docking fraction of ellagic acid, tiliroside, and kaempferol-3-o-rutoside were better than those of gallic acid, ferulic acid and vanillic acid. Additionally, by studying the effects of these six phenolic components on the LPS-induced secretion of inflammatory mediators in murine microglial (BV2) cells, it was further demonstrated that they were all capable of inhibiting the secretion of NO, IL-6, TNF-α, and IL-1ß to a certain extent. However, ellagic acid, tiliroside, and kaempferol-3-o-rutoside have better inhibitory effects compared to others. The results obtained suggest that the phenolic components extracted from ethyl acetate extracts of raspberry by molecularly imprinted polymers have the potential to inhibit the progression of Alzheimer's disease.


Assuntos
Impressão Molecular , Doenças Neurodegenerativas , Rubus , Camundongos , Animais , Rubus/química , Antioxidantes/química , Quempferóis/farmacologia , Ácido Elágico/farmacologia , Ácido Elágico/análise , Simulação de Acoplamento Molecular , Fator de Necrose Tumoral alfa , Ácido Vanílico/farmacologia , Polímeros Molecularmente Impressos , Interleucina-6 , Lipopolissacarídeos , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Ácido Gálico/farmacologia , Rutina , Mediadores da Inflamação
12.
Molecules ; 27(19)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36234945

RESUMO

Residual diatomaceous earth (RDE) from winemaking activities is a rich and currently underexploited source of phenolic compounds which ought to be recycled from the perspective of circular bioeconomy. In this work, we demonstrate the feasibility of molecularly imprinted polymers (MIPs) for the enrichment of quercetin, a flavonoid at a fairly high content in residual diatomaceous earth. These MIPs were synthesized through free radical polymerization. FTIR confirmed the integration of the functional monomers into the polymeric chains. Batch adsorption experiments were used to assess the retention and selectivity of those MIPs towards quercetin. Commercial resins were compared with the synthesized materials using the same procedures. These adsorption experiments allowed the selection of the best performing MIP for the valorization of RDE extract. This treatment consisted of saturating the selected MIP with the extract and then desorbing the retained compounds using solvents of selected compositions. The desorbed fractions were analyzed using liquid chromatography, and the results demonstrated an increase in quercetin's fractional area from 5% in the RDE extract to more than 40% in some fractions, which is roughly an eightfold enrichment of quercetin. Moreover, other flavonoids of close chemical structure to quercetin have been rather retained and enriched by the MIP.


Assuntos
Impressão Molecular , Quercetina , Adsorção , Terra de Diatomáceas , Flavonoides , Polímeros Molecularmente Impressos , Extratos Vegetais/química , Quercetina/química , Extração em Fase Sólida/métodos , Solventes
13.
Talanta ; 250: 123723, 2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35868148

RESUMO

Coffee, a beverage with a complex chemical composition, is appreciated for the sensory experience of its taste and aroma. The compound 5-(hydroxymethyl)-2-furfural (HMF) is essential for sensory characterization of the beverage, and is also used in the traceability of its production. In this work, a procedure combining salting-out assisted liquid-liquid extraction (SALLE) and an electropolymerized molecularly imprinted polymer (e-MIP) was developed for the detection and quantification of HMF in coffee samples. The sample preparation step using SALLE employed a combination of acetonitrile and phosphate-buffered saline, in a proportion of 70:30 (ACN:PBS), with addition of 0.02 g of NaCl. The new sensor (e-MIP) was prepared by electropolymerization of p-aminobenzoic acid onto a glassy carbon electrode (GCE) using cyclic voltammetry (CV). Analytical determinations were performed by differential pulse voltammetry (DPV). The linear regression correlation coefficient (r2) for the response was 0.9986. The limits of detection and quantification were 0.372 mg L-1 and 1.240 mg L-1, respectively. The repeatability and reproducibility values obtained were 6 and 10%, respectively. The recoveries for three concentration levels were between 97 and 101%. Analyses of different coffee samples showed that the HMF concentrations varied from 261.0 ± 41.0 to 770.2 ± 55.9 mg kg-1 in powdered coffee samples, and from 1510 ± 50 to 4445 ± 278 mg kg-1 in instant coffee samples. The advantages of this procedure, compared to other methods described in the literature, are its simplicity, easy operation, good selectivity and sensitivity, low cost, and minimal use of organic solvents.


Assuntos
Impressão Molecular , Ácido 4-Aminobenzoico , Acetonitrilas , Carbono/química , Café , Técnicas Eletroquímicas/métodos , Eletrodos , Furaldeído/análogos & derivados , Limite de Detecção , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Fosfatos , Polímeros/química , Reprodutibilidade dos Testes , Cloreto de Sódio , Solventes
14.
J Inherit Metab Dis ; 45(4): 696-709, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35527480

RESUMO

Phenylketonuria (PKU) is a rare genetic disorder caused by a defect in the metabolism of phenylalanine (Phe). Currently, the most commonly used treatment for PKU is dietary Phe restriction. Problems associated with Phe restricted diets include lack of universal availability, high treatment costs, and reduced adherence to continued treatment with age and finally the development of psychological and neurological problems in a significant proportion of patients despite early start of treatment. One possible approach to decreasing blood Phe level, is inhibition of GI tract absorption of this amino acid. We had previously shown that a Phe selective molecularly imprinted polymer was able to bind Phe in the GI tract and attenuate its plasma concentration. In this work, we used different orally administered Phe selective molecularly imprinted polymer doses in a PKU mouse model to further study the effects of this treatment on biochemical profile and cognitive function in test animals. Treatments started 21 days postnatally. After 3 weeks, brain and plasma amino acid profiles and brain monoaminergic neurotransmitter concentrations were measured. Behavioral profile was also evaluated. Treatment with 2% and 5% Phe selective molecularly imprinted polymer significantly reduced levels of blood Phe in PKU model animals (46% and 48% respectively) meanwhile levels of other amino acids remained unchanged. Brain dopamine concentrations in hippocampus was effectively restored by supplementation of Phe selective molecularly imprinted polymer. Finally, polymer treatment improved locomotor dysfunction in PKU model animals. Our data suggest that the Phe selective molecularly imprinted polymer can be a new candidate for treatment of PKU patients. Take home message: Orally administered Phenylalanine Selective Molecularly Imprinted Polymer is able to inhibit absorption of phenylalanine from the GI tract and may offer a new treatment, in conjunction with dietary restriction, for PKU patients.


Assuntos
Fenilalanina , Fenilcetonúrias , Administração Oral , Animais , Modelos Animais de Doenças , Camundongos , Polímeros Molecularmente Impressos , Fenilalanina/metabolismo , Fenilcetonúrias/metabolismo
15.
Artigo em Inglês | MEDLINE | ID: mdl-35537311

RESUMO

Monocrotaline (MCT), derived from most flowering plants, showed significant hepatotoxicity and carcinogenicity. Humans are easily exposed to MCT by eating traditional herbs or contaminated foods, posing a huge threat to human health. In order to selectively and conveniently separate and enrich MCT from these complex samples, we fabricated three-dimensional porous and homogeneous molecularly imprinted polymer foams (MIPFs) by using considerably inexpensive polyurethane foam (PU) as the carrier. The morphology, stability, adsorption properties and extraction parameters of MIPFs were investigated. The results indicated that an imprinted layer was coated on the surface of the carrier; the stability of MIPFs was excellent; In addition to hydrogen bonding and spatial complementarity, the electrostatic interactions were crucial for the recognition between MCT and MIPFs; MIPFs exhibited high adsorption capacity of 22.78 mg g-1, fast mass transfer rate, and satisfactory selectivity for MCT. Subsequently, MIPFs were applied as the solid phase extraction (SPE) absorbents and combined with high performance liquid chromatography (HPLC) to enrich and detect MCT in herbal plants. The results showed that MCT could be efficiently enriched, and the impurities could be dramatically reduced. MIPFs hold great potential for selective separation and detection of MCT in complex matrices, such as traditional Chinese medicine samples and food samples.


Assuntos
Impressão Molecular , Adsorção , Cromatografia Líquida de Alta Pressão/métodos , Humanos , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Monocrotalina , Polímeros/química , Extração em Fase Sólida/métodos
16.
J Hazard Mater ; 436: 129107, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35569369

RESUMO

Norfloxacin (NOR) is an antibiotic commonly used to treat humans and food-producing animals. Owing to NOR abuse, its residues are frequently found in animal-derived food products and the surrounding environment. Therefore, development of an efficient analytical technique for the selective determination of trace NOR is greatly significant for food safety and environmental protection. Here, we fabricated an ultrasensitive, label-free molecularly imprinted polymer (MIP) voltammetric sensor for the selective determination of NOR, based on an Au nanoparticle-functionalized black phosphorus nanosheet nanocomposite (BPNS-AuNP) covered by a polypyrrole-imprinted film. BPNS-AuNP nanocomposites were prepared via an in-situ one-step method without the use of reducing agents. The imprinted polypyrrole film was formed on the surface of the BPNS-AuNPs in the presence of NOR. The physical properties and electrochemical behavior of the MIP/BPNS-AuNPs were investigated using various characterization techniques, and the analytical parameters were optimized. We found that BPNS-AuNPs improve the ambient stability and electrocatalytic activity, providing a large surface area for locating a higher number of specific recognition sites. Consequently, the MIP/BPNS-AuNP/GCE showed excellent sensing performance toward NOR, with a wide linear response range (0.1 nM - 10 µM), an extremely low limit of detection (0.012 nM), and extraordinary selectivity. Moreover, the MIP/BPNS-AuNP/GCE was used to determine NOR in various experimental samples with satisfactory results.


Assuntos
Nanopartículas Metálicas , Impressão Molecular , Nanocompostos , Animais , Técnicas Eletroquímicas/métodos , Eletrodos , Ouro/química , Limite de Detecção , Nanopartículas Metálicas/química , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Nanocompostos/química , Norfloxacino , Fósforo , Polímeros/química , Pirróis
17.
Analyst ; 147(12): 2718-2730, 2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35583011

RESUMO

Effective methods are required to quantify the organochlorine pesticide procymidone due to its potentially harmful effects toward human health and the environment. Here, hydrophilic hollow imprinted microspheres were prepared via a simple method as fluorescent sensors (@MIH-prm) for the sensitive and selective detection of PRM in ginseng. A new method of adsorption efficiency evaluation for @MIH-prm was subsequently introduced (EBS%), the effective binding site, which provided a comprehensive evaluation of the performance compared with conventional methods. The results showed that @MIH-prm could detect PRM in filtered and diluted ginseng juice with high sensitivity (LOD, 0.569 nM) and a rapid detection rate (quantitative detection of PRM within 18 min). Good selectivity was observed in the presence of combinations of different pesticides, and the adsorption of PRM could be described by the pseudo-second-order kinetic model. PRM concentrations exhibited good linearity over 1-40 nM, and the accuracy (recovery rates, 99.2 to 103.1%) and precision (RSD at 1.0 × 10-9 M, 3.14%) indicated that @MIH-prm could be used for the quantitative analysis of PRM in complex matrices. Hence, @MIH-prm has good application potential in pollution control monitoring and enforcement.


Assuntos
Impressão Molecular , Panax , Compostos Bicíclicos com Pontes , Corantes , Humanos , Impressão Molecular/métodos , Polímeros Molecularmente Impressos , Panax/química , Polímeros/química
18.
J Sep Sci ; 45(13): 2415-2428, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35474633

RESUMO

A novel boronic acid and carboxyl-modified glucose molecularly imprinted polymer were prepared through suspension polymerization, which is based on 1.0 mmol glucose as a template, 1.2 mmol methacrylamidophenylboronic acid, and 6.8 mmol methacrylic acids as monomers, 19 mmol ethyleneglycol dimethacrylate, and 1 mmol methylene-bis-acrylamide as crosslinkers. The prepared glucose-molecularly imprinted polymer had a particle size of 25-70 µm, and was thermally stable below 215°C, with a specific surface area of 174.82 m2/ g and average pore size of 9.48 nm. The best selectivity between glucose and fructose was 2.71 and the maximum adsorption capacity of glucose- molecularly imprinted polymer was up to 236.32 mg/ g which was consistent with the Langmuir adsorption model. The similar adsorption abilities in six successive runs and the good desorption rate (99.4%) verified glucose-molecularly imprinted polymer could be reused. It was successfully used for extracting glucose from cellulose hydrolysis. The adsorption amount of glucose was 2.61 mg/mL and selectivity between glucose and xylose reached 4.12. A newly established chromatography (glucose-molecularly imprinted polymer) mediated hollow fiber membrane method in time separated pure glucose from cellulose hydrolysates on a large scale, and purified glucose solution with a concentration of 3.84 mg/mL was obtained, which offered a feasible way for the industrial production of glucose from cellulose hydrolysates.


Assuntos
Impressão Molecular , Adsorção , Ácidos Borônicos , Celulose , Cromatografia , Glucose , Hidrólise , Polímeros Molecularmente Impressos , Extratos Vegetais/química , Polímeros/química
19.
ACS Nano ; 16(3): 3797-3807, 2022 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-35188759

RESUMO

A core-shell molecularly imprinted polymer nanoparticle with biological enzyme functional characteristics was developed by oxidative polymerization of template protein and polydopamine on the surface of protease-copper phosphate hybrid nanoflowers by molecular imprinting technology and enzyme immobilization technology. The obtained molecularly imprinted polymer showed specific binding characteristics with the template protein. It recognized and enriched the target molecules through the surface molecularly imprinted sites of the shell structure. In addition, the bound target molecules were further degraded into fragments by nanozymes with biological enzyme characteristics in the core. In this study, molecular imprinting technology and biotechnology were combined to obtain bifunctional molecularly imprinted polymer nanoparticles that can not only enrich template molecules but also degrade them into fragments. Herein, we selected interleukin 6 (IL-6), the target molecule of cytokine release syndrome (CRS), as a template molecule, and reported a molecularly imprinted polymer with degrading enzyme properties that can rapidly reduce IL-6 levels in vivo, including a molecularly imprinted layer that can recognize and bind IL-6 and nanozymes that can degrade IL-6 and deactivate it. It is used to clear the excessive secretion of IL-6 in CRS and reduce the level of IL-6 in the body to achieve the purpose of adjuvant treatment of CRS.


Assuntos
Impressão Molecular , Polímeros Molecularmente Impressos , Síndrome da Liberação de Citocina , Humanos , Interleucina-6 , Polimerização
20.
Mikrochim Acta ; 189(1): 43, 2022 01 03.
Artigo em Inglês | MEDLINE | ID: mdl-34978614

RESUMO

Metal oxide-based macroporous ordered double affinity molecularly imprinted polymers (D-MIPs) were developed as solid phase extraction (SPE) adsorbents for the specific identification of ovalbumin (OVA) under physiological pH conditions prior to ultraviolet visible (UV-vis) spectrophotometric detection. Herein, macroporous alumina (MA) was used as a matrix; dimercaptosuccinic acid (DMSA) and 3-aminophenylboric acid (APBA) were employed as dual-functional monomers; APBA is a self-polymerizing monomer. The effects of synthesis conditions, SPE conditions as well as selectivity, reproducibility, and reusability were studied. The co-modification of DMSA and boronate affinity renders the adsorbent exhibiting a high adsorption capacity (114.4 mg g-1) and short equilibrium time (30 min). The surface imprinting technology causes the adsorbent to have high selectivity towards OVA. The OVA recovery range is 91.1-99.6%. This study provides a promising method for the enrichment of OVA and other cis-diol-containing analytes in complex biological samples. A novel metal oxide-based macroporous ordered nanoparticle with a combination of DMSA and boronate affinity was successfully prepared for specific separation and enrichment of glycoprotein from complex biological samples.


Assuntos
Óxido de Alumínio/química , Boratos/química , Contaminação de Alimentos/análise , Glicoproteínas/análise , Polímeros Molecularmente Impressos/química , Succímero/química , Análise de Alimentos , Tamanho da Partícula , Porosidade , Propriedades de Superfície
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