Carvedilol-Imprinted Polymer: Rational design and selectivity studies

Magnetic and mesoporous molecularly imprinted polymer synthesized by rational computation design: Sample preparation and analysis of ractopamine

Through density functional theory calculations was studied theoretically the formation process of a magnetic and mesoporous molecularly imprinted polymer for ractopamine (RAC), evaluating the molecular electrostatic potential map, functional monomers, functional monomer / template stoichiometry and crosslink agents. The results revealed that the best conditions for the synthesis were established with acrylic acid as functional monomer in a 1: 4 stoichiometry using acetonitrile as the solvent and ethylene glycol dimethacrylate as crosslink agent. It was observed that nine hydrogen bonds established between the RAC and acrylic acid play a key role on the pre-polymerization complex. In addition, three analytical methods using HPLC, UHPLC and CE instruments were optimized for rapid analysis. The adsorbent was experimentally synthesized considering the best conditions found at the molecular level and characterized by FTIR, DRX, TGA, SEM, TEM, surface analysis, and wettability. After that, the synthesized material was used in magnetic solid phase extraction combined with capillary electrophoresis in a preliminary RAC recovery study from milk samples. Finally, greenness metric with a score of 0.55 have been obtained for the sample preparation procedure using the online AGREEprep metric.

Molecularly-Imprinted SERS: A Potential Method for Bioanalysis

The most challenging step in developing bioanalytical methods is finding the best sample preparation method. The matrix interference effect of biological sample become a reason of that. Molecularly imprinted SERS become a potential analytical method to be developed to answer this challenge. In this article, we review recent progress in MIP SERS application particularly in bioanalysis. Begin with the explanation about molecular imprinting technique and component, SERS principle, the combination of MIP SERS, and follow by various application of MIP SERS for analysis. Finally, the conclusion and future perspective were also discussed.

Atenolol-imprinted polymer: a DFT study

The purpose of this work was to investigate, via DFT calculations, the molecularly imprinted polymer (MIP) for atenolol (ATL) β-blocker evaluating distinct functional monomers (FMs), solvents, and cross-linker agents (CLAs). As the main result, we could determine from structural and thermodynamic data the best MIP synthesis protocol as being: p-vinyl benzoic acid (APV) as FM, toluene as solvent, and pentaerythritol triacrylate (PETRA) as CLA. We believe this rational design can be very useful for experimentalists in an attempt to perform an efficient synthesis of a MIP for this important β-blocker drug.

The Use of Computational Methods for the Development of Molecularly Imprinted Polymers

Recent years have witnessed a dramatic increase in the use of theoretical and computational approaches in the study and development of molecular imprinting systems. These tools are being used to either improve understanding of the mechanisms underlying the function of molecular imprinting systems or for the design of new systems. Here, we present an overview of the literature describing the application of theoretical and computational techniques to the different stages of the molecular imprinting process (pre-polymerization mixture, polymerization process and ligand-molecularly imprinted polymer rebinding), along with an analysis of trends within and the current status of this aspect of the molecular imprinting field.

A Review on Molecularly Imprinted Polymers Preparation by Computational Simulation-Aided Methods

Molecularly imprinted polymers (MIPs) are obtained by initiating the polymerization of functional monomers surrounding a template molecule in the presence of crosslinkers and porogens. The best adsorption performance can be achieved by optimizing the polymerization conditions, but this process is time consuming and labor-intensive. Theoretical calculation based on calculation simulations and intermolecular forces is an effective method to solve this problem because it is convenient, versatile, environmentally friendly, and inexpensive. In this article, computational simulation modeling methods are introduced, and the theoretical optimization methods of various molecular simulation calculation software for preparing molecularly imprinted polymers are proposed. The progress in research on and application of molecularly imprinted polymers prepared by computational simulations and computational software in the past two decades are reviewed. Computer molecular simulation methods, including molecular mechanics, molecular dynamics and quantum mechanics, are universally applicable for the MIP-based materials. Furthermore, the new role of computational simulation in the future development of molecular imprinting technology is explored.

Molecularly imprinted polymer-based electrochemical sensor for the determination of endocrine disruptor bisphenol-A in bovine milk

Bisphenol A (BPA) contamination from food packaging material has been a major concern in recent years, due to its potential endocrine-disrupting effects on humans, especially infants and children. This paper reports the detection of BPA using an electrochemical sensor based on molecularly imprinted polymer (MIP). Electrochemically reduced graphene oxide coated glassy carbon electrode used for this study. Density functional theory (DFT) at B3LYP/6-31 + G (d,p) level was used to calculate the molecular-level interaction between BPA and MIP. The pyrrole electrochemically polymerized in the presence of template molecule BPA on the electrode surface. BPA imprinted cavities were formed by removing entrapped BPA molecules from the polypyrrole film. MIP electrode was used for the determination of BPA in standard and real samples by differential pulse voltammetry. The peak current shows the linear relationship to the logarithmic concentration of BPA between 750 and 0.5 nmolL^-1 with a correlation coefficient, R² = 0.992. The limit of detection was found to be 0.2 nmolL^-1 (S/N = 3). The reproducibility and repeatability of the sensor were also studied.

An Update on Molecularly Imprinted Polymer Design through a Computational Approach to Produce Molecular Recognition Material with Enhanced Analytical Performance

Molecularly imprinted polymer (MIP) computational design is expected to become a routine technique prior to synthesis to produce polymers with high affinity and selectivity towards target molecules. Furthermore, using these simulations reduces the cost of optimizing polymerization composition. There are several computational methods used in MIP fabrication and each requires a comprehensive study in order to select a process with results that are most similar to properties exhibited by polymers synthesized through laboratory experiments. Until now, no review has linked computational strategies with experimental results, which are needed to determine the method that is most appropriate for use in designing MIP with high molecular recognition. This review will present an update of the computational approaches started from 2016 until now on quantum mechanics, molecular mechanics and molecular dynamics that have been widely used. It will also discuss the linear correlation between computational results and the polymer performance tests through laboratory experiments to examine to what extent these methods can be relied upon to obtain polymers with high molecular recognition. Based on the literature search, density functional theory (DFT) with various hybrid functions and basis sets is most often used as a theoretical method to provide a shorter MIP manufacturing process as well as good analytical performance as recognition material.

Electroanalysis Applied to Compatibility and Stability Assays of Drugs: Carvedilol Study Case

Carvedilol (CRV) is a non-selective blocker of α and β adrenergic receptors, which has been extensively used for the treatment of hypertension and congestive heart failure. Owing to its poor biopharmaceutical properties, CRV has been incorporated into different types of drug delivery systems and this necessitates the importance of investigating their compatibility and stability. In this sense, we have investigated the applicability of several electroanalytical tools to assess CRV compatibility with lipid excipients. Voltammetric and electrochemical impedance spectroscopy techniques were used to evaluate the redox behavior of CRV and lipid excipients. Results showed that Plurol^® isostearic, liquid excipient, and stearic acid presented the greatest anode peak potential variation, and these were considered suitable excipients for CRV formulation. CRV showed the highest stability at room temperature and at 50 °C when mixed with stearic acid (7% w/w). The results also provided evidence that electrochemical methods might be feasible to complement standard stability/compatibility studies related to redox reactions.

Theoretical research of molecular imprinted polymers formed from formaldehyde and methacrylic acid

In recent years, with the development of molecular imprinting technology, the imprinting sites, nature of imprinting, selection of functional monomers, cross-linking agents, solvents, and the optimization of the imprinting ratio are all the hot spots of researchers. In this work, the theoretical prediction of the self-assembly system of formaldehyde (HCHO) molecularly imprinted polymer was carried out by the B3LYP/6-31 G(d,p) method. The geometric configuration and active sites of the stable complex of HCHO and methacrylic acid (MAA) were analyzed. The selection of the imprinting ratios, cross-linking agents, and solvents was discussed. The topological properties of electron density of HCHO-MAA complex were considered by using the topological analysis method of chemical bond electron density based on valence bond theory. This study cannot only reveal the relationship between the imprinting mechanism of molecularly imprinted polymers and the molecular structure and properties of molecularly imprinted polymers but also provide valuable reference for the design and preparation of molecularly imprinted polymers.

Magnetic molecularly imprinted conducting polymer for determination of praziquantel enantiomers in milk

A new selective adsorbent based on magnetic molecularly imprinted conducting polymer was firstly synthetized and applied to the magnetic solid phase extraction (MSPE) for the determination of PZQ enantiomers in milk samples.