Molecularly imprinted nanozymes with faster catalytic activity and better specificity

Nanoscale ◽  
2019 ◽  
Vol 11 (11) ◽  
pp. 4854-4863 ◽  
Author(s):  
Zijie Zhang ◽  
Yuqing Li ◽  
Xiaohan Zhang ◽  
Juewen Liu

Molecular imprinting accelerates nanozyme catalysis and improves specificity attributable to selective adsorption of imprinted substrate, decreasing activation energy and facilitating product release.

2013 ◽  
Vol 316-317 ◽  
pp. 1018-1023
Author(s):  
Xin Zhu Li ◽  
Ji Shi Zhang

Cr-substituted mesoporous aluminophosphate molecular sieve (Cr-MAP) was synthesized and characterized. Crystallization kinetics curves measured as an index to the relative degree of crystallinity, according to the Arrhenius equation to calculate the apparent nucleation activation energy and crystal growth activation energy of Cr-MAP, which was 63.7 and 14.7 kJ• mol-1, respectively. Cr-MAP had highly catalytic activity for fabricating acetophenone by selectively oxizing ethylbenzene. Using tert-butylhydroperoxide as oxidant and chlorobenzene as solvent at 100 °C for 8 h, acetophenone selectivity, acetophenone yield and ethylbenzene conversion reaches 85.4, 62.2 and 72.8 %, respectively.


Sensors ◽  
2021 ◽  
Vol 21 (7) ◽  
pp. 2406
Author(s):  
Mashaalah Zarejousheghani ◽  
Parvaneh Rahimi ◽  
Helko Borsdorf ◽  
Stefan Zimmermann ◽  
Yvonne Joseph

Globally, there is growing concern about the health risks of water and air pollution. The U.S. Environmental Protection Agency (EPA) has developed a list of priority pollutants containing 129 different chemical compounds. All of these chemicals are of significant interest due to their serious health and safety issues. Permanent exposure to some concentrations of these chemicals can cause severe and irrecoverable health effects, which can be easily prevented by their early identification. Molecularly imprinted polymers (MIPs) offer great potential for selective adsorption of chemicals from water and air samples. These selective artificial bio(mimetic) receptors are promising candidates for modification of sensors, especially disposable sensors, due to their low-cost, long-term stability, ease of engineering, simplicity of production and their applicability for a wide range of targets. Herein, innovative strategies used to develop MIP-based sensors for EPA priority pollutants will be reviewed.


e-Polymers ◽  
2007 ◽  
Vol 7 (1) ◽  
Author(s):  
Francesco Puoci ◽  
Francesca Iemma ◽  
Giuseppe Cirillo ◽  
Sonia Trombino ◽  
Roberta Cassano ◽  
...  

AbstractIn this work the preparation and evaluation of molecularly imprinted polymers (MIPs) based on 2-hydroxyethylmetacrylate (HEMA) for selective recovery of cholesterol from aqueous media are reported. HEMA was used as functional monomer in order to maximize the hydrogen bond forming both in prepolymerization complex and in rebinding experiments which were performed in polar solvents; in particular, an acetonitrile:water (7:3 v/v) mixture was employed. The templating effect is clearly seen in the capacity of the synthesized polymers to bind cholesterol, and their selectivity was evaluated using two steroids quite similar to cholesterol such as progesterone and hydrocortisone which are less effectively bound by the matrices.


2014 ◽  
Vol 5 (16) ◽  
pp. 4764-4771 ◽  
Author(s):  
Yuri Kamon ◽  
Ryo Matsuura ◽  
Yukiya Kitayama ◽  
Tooru Ooya ◽  
Toshifumi Takeuchi

We demonstrate a novel synthetic route for molecularly imprinted polymer (MIP) thin films using a bottom-up approach utilizing protein–ligand specific interactions.


2019 ◽  
Author(s):  
Martina Tommasini ◽  
Elena Pellizzoni ◽  
Valentina Iacuzzi ◽  
Elena Marangon ◽  
Paola Posocco ◽  
...  

A series of fluorescent molecularly imprinted nanogels to detect irinotecan (CPT11) were prepared and characterized. A set of amino acids and napthalimide polymerisable derivatives allowed to obtain polymers as soluble fluorescent nanoparticles by high dilution imprinted synthesis. The direct detection of irinotecan in human plasma was obtained by fluorescence quenching of the naphtalimide-based imprinted materials. The plasma sample treated with acetonitrile allowed the detection of irinotecan in the 10nM – 30μM range. The LOD was 9.4 nM, with within-run variability 10% and day to day variability 13%.<br>


2020 ◽  
Author(s):  
Alfredo Calderón-Cárdenas ◽  
Enrique A. Paredes-Salazar ◽  
Hamilton Varela

<div> <div> <div> <p>Activation energy is a well-known empirical parameter in chemical kinetics that characterises the dependence of the chemical rate coefficients on the temperature and provides information to compare the intrinsic activity of the catalysts. However, the determination and interpretation of the apparent activation energy in multistep reactions is not an easy task. For this purpose, the concept of degree of rate control is convenient, which comprises a mathematical approach for analyzing reaction mechanisms and chemical kinetics. Although this concept has been used in catalysis, it has not yet been applied in electrocatalytic systems, whose ability to control the potential across the solid/liquid interface is the main difference with heterogenous catalysis, and the electrical current is commonly used as a measure of the reaction rate. Herein we use the definition of ‘degree of rate control for elementary step’ to address some of the drawbacks that frequently arise with interpreting apparent activation energy as a measure of intrinsic electrocatalytic activity of electrode. For this, an electrokinetic model Langmuir-Hinshelwood-like is used for making numerical experiments and verifying the proposed ideas. The results show that to improve the catalytic activity of an electrode material, it must act upon the reaction steps with the highest normalised absolute values of degree of rate control. On the other hand, experiments at different applied voltages showed that if the electroactive surface poisoning process take place, changes in 𝐸𝑎𝑝𝑝 can not be used to compare the catalytic activity of the electrodes. Finally, the importance of making measurements at steady-state to avoid large errors in the calculations of apparent activation energy is also discussed. </p> </div> </div> </div>


2014 ◽  
Vol 605 ◽  
pp. 67-70 ◽  
Author(s):  
Mohsen Rahiminezhad ◽  
Seyed Jamaleddin Shahtaheri ◽  
Mohammad Reza Ganjali ◽  
Abbas Rahimi Rahimi Forushani

Molecular imprinting technology has become an interesting research area to the preparation of specific sorbent material for environmental and occupational sample preparation techniques (1). In the molecular imprinting technology, specific binding sites have been formed in polymeric matrix, which often have an affinity and selectivity similar to antibody-antigen systems (2). In molecular imprinted technology, functional monomers are arranged in a complementary configuration around a template molecule, then, cross-linker and solvent are also added and the mixture is treated to give a porous material containing nono-sized binding sites. After extraction of the template molecule by washing, vacant imprinted sites will be left in polymer, which are available for rebinding of the template or its structural analogue (3). The stability, convention of preparation and low cost of these materials make them particularly attractive (4). These synthetic materials have been used for capillary electrochromatography (5), chromatography columns (6), sensors (7), and catalyze system (8). Depending on the molecular imprinting approach, different experimental variables such as the type and amounts of functional monomers, porogenic solvent, initiator, monomer to cross-linker ratio, temperature, and etc may alter the properties of the final polymeric materials. In this work, chemometric approach based on Central Composite Design (CCD) was used to design the experiments as well as to find the optimum conditions for preparing appropriate diazinon molecularly imprinted polymer.


2016 ◽  
Vol 4 (44) ◽  
pp. 7138-7145 ◽  
Author(s):  
Hirobumi Sunayama ◽  
Takeo Ohta ◽  
Atsushi Kuwahara ◽  
Toshifumi Takeuchi

An antibiotic-imprinted cavity with two different fluorescent dyes was prepared by molecular imprinting and subsequent post-imprinting modifications (PIMs), for the readout of a specific binding event as a fluorescence signal.


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