Typical Fluorescent Sensors Exploiting Molecularly Imprinted Hydrogels for Environmentally and Medicinally Important Analytes Detection

In this work, two typical fluorescent sensors were generated by exploiting molecularly imprinted polymeric hydrogels (MIPGs) for zearalenone (ZON) and glucuronic acid (GA) detection, via the analyte’s self-fluorescence property and receptor’s fluorescence effect, respectively. Though significant advances have been achieved on MIPG-fluorescent sensors endowed with superior stability over natural receptor-sensors, there is an increasing demand for developing sensing devices with cost-effective, easy-to-use, portable advantages in terms of commercialization. Zooming in on the commercial potential of MIPG-fluorescent sensors, the MIPG_ZON is synthesized using zearalanone (an analogue of ZON) as template, which exhibits good detection performance even in corn samples with a limit of detection of 1.6 μM. In parallel, fluorescein-incorporated MIPG_GA is obtained and directly used for cancer cell imaging, with significant specificity and selectivity. Last but not least, our consolidated application results unfold new opportunities for MIPG-fluorescent sensors for environmentally and medicinally important analytes detection.

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Molecularly Imprinted Nanoparticles Based Sensor for Cocaine Detection

Biosensors ◽

10.3390/bios10030022 ◽

2020 ◽

Vol 10 (3) ◽

pp. 22 ◽

Cited By ~ 4

Author(s):

Roberta D’Aurelio ◽

Iva Chianella ◽

Jack A. Goode ◽

Ibtisam E. Tothill

Keyword(s):

Electrochemical Impedance ◽

Limit Of Detection ◽

Solid Phase ◽

Cost Effective ◽

Cross Reactivity ◽

P Value ◽

Sensing Element ◽

Molecularly Imprinted ◽

Cost Effective Method ◽

Cocaine Detection

The development of a sensor based on molecularly imprinted polymer nanoparticles (nanoMIPs) and electrochemical impedance spectroscopy (EIS) for the detection of trace levels of cocaine is described in this paper. NanoMIPs for cocaine detection, synthesized using a solid phase, were applied as the sensing element. The nanoMIPs were first characterized by Transmission Electron Microscopy (TEM) and Dynamic Light Scattering and found to be ~148.35 ± 24.69 nm in size, using TEM. The nanoMIPs were then covalently attached to gold screen-printed electrodes and a cocaine direct binding assay was developed and optimized, using EIS as the sensing principle. EIS was recorded at a potential of 0.12 V over the frequency range from 0.1 Hz to 50 kHz, with a modulation voltage of 10 mV. The nanoMIPs sensor was able to detect cocaine in a linear range between 100 pg mL−1 and 50 ng mL−1 (R2 = 0.984; p-value = 0.00001) and with a limit of detection of 0.24 ng mL−1 (0.70 nM). The sensor showed no cross-reactivity toward morphine and a negligible response toward levamisole after optimizing the sensor surface blocking and assay conditions. The developed sensor has the potential to offer a highly sensitive, portable and cost-effective method for cocaine detection.

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Preparation and characterization of molecularly imprinted solid-phase extraction column coupled with high-performance liquid chromatography for selective determination of melamine

Royal Society Open Science ◽

10.1098/rsos.180750 ◽

2018 ◽

Vol 5 (9) ◽

pp. 180750 ◽

Cited By ~ 3

Author(s):

Q. Zhou ◽

X. C. Tan ◽

X. J. Guo ◽

Y. J. Huang ◽

H. Y. Zhai

Keyword(s):

Solid Phase Extraction ◽

High Performance ◽

Limit Of Detection ◽

Solid Phase ◽

Cost Effective ◽

Extraction Column ◽

Phase Extraction ◽

Molecularly Imprinted ◽

Selective Determination ◽

Solid Phase Extraction Column

We synthesized a selective molecularly imprinted solid-phase extraction (MIP-SPE) column and established an extraction and enrichment method using this MIP-SPE column. By coupling with HPLC, we developed a new method to detect trace amounts of melamine in eggs. The MIP-SPE column was synthesized by in situ thermal-initiated polymerization using melamine as the template, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker and azodiisobutyronitrile as the initiator. HPLC was used to evaluate the identification and enrichment capability of the MIP-SPE column and for the measurement of melamine in the sample. The melamine concentration exhibited an excellent linear relationship in the range of 0.1–25.0 µg ml −1 ( r = 0.9983). The identification capability of the MIP-SPE column was apparently superior to that of the non-imprinted polymer solid-phase extraction column; an average enrichment factor of 46.8-fold (RSD = 3.5%) was obtained for 0.4 µg ml −1 melamine by the MIP-SPE column. When the MIP-SPE HPLC method was applied to the detection of melamine in eggs, an average recovery rate of 93.5–102.0% (RSD = 3.6–4.9%) and a limit of detection of 0.05 µg kg −1 were obtained. This method is simple, fast and cost-effective; thus, it can greatly simplify the pre-treatment of complex samples and can be used in the detection of residual melamine in eggs and other products.

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Competitive pseudo-ELISA based on molecularly imprinted nanoparticles for microcystin-LR detection in water

Pure and Applied Chemistry ◽

10.1515/pac-2018-1207 ◽

2019 ◽

Vol 91 (10) ◽

pp. 1593-1604

Author(s):

Yadiris Garcia ◽

Francesco Canfarotta ◽

Katarzyna Smolinska-Kempisty ◽

Sergey A. Piletsky ◽

Eduardo Pereira

Keyword(s):

Water Samples ◽

Limit Of Detection ◽

Cost Effective ◽

Cross Reactivity ◽

Molecularly Imprinted ◽

The Public ◽

Analytical Recovery ◽

Cost Effective Alternative ◽

Molecularly Imprinted Nanoparticles ◽

The Stability

Abstract Microcystins (MCs) are dangerous cyanotoxins for the public health, and microcystin-LR (MC-LR) is one of most toxic, dangerous, and frequently found in water bodies. Typically, the detection of MCs is carried out by means of competitive ELISAs which, however, need special precautions for handling and storage, due to the stability of the antibodies used in this test. Molecularly imprinted nanoparticles (nanoMIPs) represents more robust and cost-effective alternative to antibodies. In this work, we developed a competitive pseudo-ELISA based on nanoMIPs (which are used in place of natural antibodies), for the detection of microcystin-LR (MC-LR). This pseudo-ELISA showed a linear response towards MC-LR, showing high affinity and low cross-reactivity against another analogue toxin (microcystin-YR). The analytical recovery of MC-LR in the analysis of water samples by the proposed pseudo-ELISA was 96 %–130 % and the limit of detection was 2.64 × 10−4 nM. The obtained results suggest that this competitive pseudo-ELISA could have high potential in the detection of toxins, due to its rapid, sensitive and accurate detection of toxin in water samples.

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Liquid Chromatography Analysis of Clozapine in Rat Brain Tissue, Using its Molecularly Imprinted Polymer after Administration of Toxic Dose of Drug and Lipid Emulsion Therapy

Current Pharmaceutical Analysis ◽

10.2174/1573412914666180111160741 ◽

2019 ◽

Vol 15 (3) ◽

pp. 251-257

Author(s):

Bahareh Sadat Yousefsani ◽

Seyed Ahmad Mohajeri ◽

Mohammad Moshiri ◽

Hossein Hosseinzadeh

Keyword(s):

Rat Brain ◽

Brain Tissue ◽

Molecularly Imprinted Polymer ◽

Lipid Emulsion ◽

Limit Of Detection ◽

Imprinted Polymer ◽

Toxic Dose ◽

Molecularly Imprinted ◽

The Brain ◽

Rat Brain Tissue

Background:Molecularly imprinted polymers (MIPs) are synthetic polymers that have a selective site for a given analyte, or a group of structurally related compounds, that make them ideal polymers to be used in separation processes.Objective:An optimized molecularly imprinted polymer was selected and applied for selective extraction and analysis of clozapine in rat brain tissue.Methods:A molecularly imprinted solid-phase extraction (MISPE) method was developed for preconcentration and cleanup of clozapine in rat brain samples before HPLC-UV analysis. The extraction and analytical process was calibrated in the range of 0.025-100 ppm. Clozapine recovery in this MISPE process was calculated between 99.40 and 102.96%. The limit of detection (LOD) and the limit of quantification (LOQ) of the assay were 0.003 and 0.025 ppm, respectively. Intra-day precision values for clozapine concentrations of 0.125 and 0.025 ppm were 5.30 and 3.55%, whereas inter-day precision values of these concentrations were 9.23 and 6.15%, respectively. In this study, the effect of lipid emulsion infusion in reducing the brain concentration of drug was also evaluated.Results:The data indicated that calibrated method was successfully applied for the analysis of clozapine in the real rat brain samples after administration of a toxic dose to animal. Finally, the efficacy of lipid emulsion therapy in reducing the brain tissue concentration of clozapine after toxic administration of drug was determined.Conclusion:The proposed MISPE method could be applied in the extraction and preconcentration before HPLC-UV analysis of clozapine in rat brain tissue.

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Green Synthesis and Spectroscopic Studies of Ag-rGO Nanocomposites for Highly Selective Mercury (II) Sensing

Nanoscience &Nanotechnology-Asia ◽

10.2174/2210681207666170705143629 ◽

2018 ◽

Vol 9 (1) ◽

pp. 101-108 ◽

Cited By ~ 1

Author(s):

Shubhangi J. Mane-Gavade ◽

Sandip R. Sabale ◽

Xiao-Ying Yu ◽

Gurunath H. Nikam ◽

Bhaskar V. Tamhankar

Keyword(s):

Green Synthesis ◽

Color Change ◽

Limit Of Detection ◽

Aqueous Media ◽

Suitable Condition ◽

Cost Effective ◽

Spectroscopic Studies ◽

Calibration Plot ◽

First Time

Introduction: Herein we report the green synthesis and characterization of silverreduced graphene oxide nanocomposites (Ag-rGO) using Acacia nilotica gum for the first time. Experimental: We demonstrate the Hg2+ ions sensing ability of the Ag-rGO nanocomposites form aqueous medium. The developed colorimetric sensor method is simple, fast and selective for the detection of Hg2+ ions in aqueous media in presence of other associated ions. A significant color change was noticed with naked eye upon Hg2+ addition. The color change was not observed for cations including Sr2+, Ni2+, Cd2+, Pb2+, Mg2+, Ca2+, Fe2+, Ba2+ and Mn2+indicating that only Hg2+ shows a strong interaction with Ag-rGO nanocomposites. Under the most suitable condition, the calibration plot (A0-A) against concentration of Hg2+ was linear in the range of 0.1-1.0 ppm with a correlation coefficient (R2) value 0.9998. Results & Conclusion The concentration of Hg2+ was quantitatively determined with the Limit of Detection (LOD) of 0.85 ppm. Also, this method shows excellent selectivity towards Hg2+ over nine other cations tested. Moreover, the method offers a new cost effective, rapid and simple approach for the detection of Hg2+ in water samples.

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KLa(0.95−x)GdxF4:Eu3+ hexagonal phase nanoparticles as luminescent probes for in vitro Huh-7 cancer cell imaging

Dalton Transactions ◽

10.1039/d1dt00539a ◽

2021 ◽

Vol 50 (15) ◽

pp. 5197-5207

Author(s):

Mohini Gupta ◽

Rajamani Nagarajan ◽

Chitteti Ramamurthy ◽

Perumal Vivekanandan ◽

G. Vijaya Prakash

Keyword(s):

Liver Cancer ◽

Cancer Cell ◽

Cell Imaging ◽

Hexagonal Phase ◽

Liver Cancer Cell ◽

Luminescent Probes ◽

Cancer Cell Imaging ◽

Site Selective

Strong and site selective red-emitting photoluminescent/MRI multi-functional KLa(0.95−x)GdxF4:Eu3+ (x = 0–0.4) bio-compatible nanomaterials for targeted in-vitro liver cancer cell imaging.

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Pitfalls in the Immunochemical Determination of β‑Lactam Antibiotics in Water

Antibiotics ◽

10.3390/antibiotics10030298 ◽

2021 ◽

Vol 10 (3) ◽

pp. 298

Author(s):

Alexander Ecke ◽

Rudolf J. Schneider

Keyword(s):

Limit Of Detection ◽

Cost Effective ◽

Enzyme Linked Immunosorbent Assay ◽

Degree Of Hydrolysis ◽

Site Analysis ◽

Antibody Recognition ◽

Immunochemical Determination ◽

Key Factor ◽

Lactam Ring

Contamination of waters with pharmaceuticals is an alarming problem as it may support the evolution of antimicrobial resistance. Therefore, fast and cost-effective analytical methods for potential on-site analysis are desired in order to control the water quality and assure the safety of its use as a source of drinking water. Antibody-based methods, such as the enzyme-linked immunosorbent assay (ELISA), can be helpful in this regard but can also have certain pitfalls in store, depending on the analyte. As shown here for the class of β-lactam antibiotics, hydrolysis of the β‑lactam ring is a key factor in the immunochemical analysis as it influences antibody recognition. With the antibody used in this study, the limit of detection (LOD) in the immunoassay could be significantly reduced by hydrolysis for the five tested penicillins, with the lowest LOD for carbenicillin (0.2 nmol/L) and the greatest impact on penicillins G and V (reduction by 85%). In addition to enhanced quantification, our strategy also provides access to information about the degree of hydrolysis in water samples as shown for the most abundant penicillin amoxicillin.

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A Molecularly Imprinted Polymer for Selective Extraction of Phenolic Acids from Human Urine

Applied Sciences ◽

10.3390/app11041577 ◽

2021 ◽

Vol 11 (4) ◽

pp. 1577

Author(s):

Marco Mora-Granados ◽

David González-Gómez ◽

Jin Su Jeong ◽

Alejandrina Gallego-Picó

Keyword(s):

Phenolic Acids ◽

Molecularly Imprinted Polymer ◽

Human Urine ◽

Limit Of Detection ◽

Ph Dependence ◽

Selective Extraction ◽

Screening Methods ◽

Specific Method ◽

Imprinted Polymer ◽

Molecularly Imprinted

Studies for monitoring the bioavailability of dietary flavonoid compounds generate great interest. Among them, low-molecular-weight phenolic acids, secondary metabolites present in colonic catabolism and urinary excretion, have been proposed as biomarkers of polyphenol intake. Using 4-hydroxyphenylacetic acid as a template, a molecularly imprinted polymer (MIP) was synthesized for selective extraction of these hydroxylated metabolites from human urine samples and posterior analysis in an HPLC-DAD-MS system. Polymers were characterized by Scanning electron microscopy (SEM), Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR), Brunauer-Emmett-Teller (BET) method, and binding experiments. MIP presents specific recognition ability for template and analogues molecules. This capacity of recognition and the pH dependence of the binding strength was also studied. The method was validated over a concentration range of 0.25–40 mg/L, r2 > 0.995. In the optimized conditions, the recovery value was 94% with RSD 1.2%. The Limit of Detection (LOD) and Limit of Quantification (LOQ) were 1.22 and 3.69 mg/L, respectively. In our knowledge, it is the first time that this methodology is applied to analyze urinary catabolites of the polyphenol compound and to provide a specific method and simple analysis alternative. The selective extraction of these metabolites improves the application and results obtained by other less sensitive analysis methods than the validation method. It also facilitates the development of new screening methods.

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Lanthanide clusters of phenanthroline containing a pyridine–pyrazole based ligand: magnetism and cell imaging

Dalton Transactions ◽

10.1039/d0dt04122j ◽

2021 ◽

Vol 50 (10) ◽

pp. 3593-3609 ◽

Cited By ~ 1

Author(s):

Avik De ◽

Sukhen Bala ◽

Sayan Saha ◽

Krishna Sundar Das ◽

Sohel Akhtar ◽

...

Keyword(s):

Magnetic Properties ◽

Cancer Cell ◽

Luminescence Property ◽

Cell Imaging ◽

Cancer Cell Imaging

In this contribution, we report the synthesis, characterization and luminescence–magnetic properties of Ln-clusters (Ln = Gd3+, Eu3+ and Tb3+) using a new pyridine–pyrazole functionalized ligand fitted with a chromophoric phenanthroline backbone. We have applied the luminescence property of clusters for cancer cell imaging.

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