Development of a molecularly imprinted solid-phase extraction sorbent for the selective extraction of telmisartan from human urine

Recent molecularly imprinted polymers applications in bioanalysis

Molecular imprinted polymers (MIPs) as extraordinary compounds with unique features have presented a wide range of applications and benefits to researchers. In particular when used as a sorbent in sample preparation methods for the analysis of biological samples and complex matrices. Its application in the extraction of medicinal species has attracted much attention and a growing interest. This review focus on articles and research that deals with the application of MIPs in the analysis of components such as biomarkers, drugs, hormones, blockers and inhibitors, especially in biological matrices. The studies based on MIP applications in bioanalysis and the deployment of MIPs in high-throughput settings and optimization of extraction methods are presented. A review of more than 200 articles and research works clearly shows that the superiority of MIP techniques lies in high accuracy, reproducibility, sensitivity, speed and cost effectiveness which make them suitable for clinical usage. Furthermore, this review present MIP-based extraction techniques and MIP-biosensors which are categorized on their classes based on common properties of target components. Extraction methods, studied sample matrices, target analytes, analytical techniques and their results for each study are described. Investigations indicate satisfactory results using MIP-based bioanalysis. According to the increasing number of studies on method development over the last decade, the use of MIPs in bioanalysis is growing and will further expand the scope of MIP applications for less studied samples and analytes.

Preparation of Molecularly Imprinted Polymer Microspheres for Selective Solid-Phase Extraction of Capecitabine in Urine Samples

Molecularly imprinted solid-phase extraction to treat biological samples has attracted considerable attention. Herein, molecularly imprinted polymer (MIP) microspheres with porous structures were prepared by a combined suspension-iniferter polymerization method using capecitabine (CAP) as a template molecule. This material was subsequently used as a solid-phase extraction agent to separate and enrich drug molecules in urine samples. UV analysis revealed that methacrylate (MAA) was an ideal functional monomer, and 1H Nuclear Magnetic Resonance (1H NMR), Ultraviolet (UV), and Fourier transform-infrared (FT-IR) spectroscopic analyses were used to study the interaction forces between MAA and CAP, demonstrating that hydrogen bonding was the primary interaction force. MIPs with outstanding selectivity were successfully prepared, and the analysis of their surface morphology and chemical structure revealed a spherical morphology with small holes distributed across a rough surface. This surface morphology significantly reduced the mass transfer resistance of template molecules, providing an ideal template recognition effect. Using the molecularly imprinted solid-phase extraction method, CAP and the structural analog cytidine (CYT) were pretreated in urine samples and quantified by HPLC. The results showed that CAP and CYT recoveries reached 97.2% and 39.8%, respectively, with a limit of detection of 10.0–50.0 µg·mL−1. This study provides a novel approach to drug molecule pretreatment that can be applied in drug separation and functional materials science fields.

Recent advances and applications of molecularly imprinted polymers in solid-phase extraction for real sample analysis

Sample pretreatment is essential for the analysis of complicated real samples due to their complex matrices and low analyte concentrations. Among all sample pretreatment methods, solid-phase extraction is arguably the most frequently used one. However, the majority of available solid-phase extraction adsorbents suffer from limited selectivity. Molecularly imprinted polymers are a type of tailor-made artificial antibodies and receptors with specific recognition sites for target molecules. Using molecularly imprinted polymers instead of conventional adsorbents can greatly improve the selectivity of solid-phase extraction, and therefore molecularly imprinted polymer-based solid-phase extraction has been widely applied to separation, clean up and/or preconcentration of target analytes in various kinds of real samples. In this article, after a brief introduction, the recent developments and applications of molecularly imprinted polymer-based solid-phase extraction for determination of different analytes in complicated real samples during the 2015-2020 are reviewed systematically, including the solid-phase extraction modes, molecularly imprinted adsorbent types and their preparations, and the practical applications of solid-phase extraction to various real samples (environmental, food, biological, and pharmaceutical samples). Finally, the challenges and opportunities of using molecularly imprinted polymer-based solid-phase extraction for real sample analysis are discussed.

Molecularly Imprinted Solid-Phase Extraction Sorbents for the Selective Extraction of Drugs from Human Urine

Development of molecularly imprinted solid-phase extraction (MISPE) sorbents for the removal of drugs from human urine is described. MISPE sorbents are synthesized through free radical polymerization mechanism and non-covalent imprinting approach. After the completion of the polymerization, bulk polymer is ground using an analytical mill and then wet-sieved. Later on, MISPE sorbent has been dry-packed into solid-phase extraction cartridges after the extraction of template drug molecule. Eluates from the cartridges are analyzed using a spectrophotometer or spectrofluorimeter for the determination of target analyte by referring to the calibration curves.

Application of the artificial neural network and imperialist competitive algorithm for optimization of molecularly imprinted solid phase extraction of methylene blue

In this study, a hybrid of the artificial neural network-imperialist competitive algorithm (ANN-ICA) has been applied for prediction and optimization of the molecularly imprinted solid phase extraction method. This method has been used for the pre-concentration of methylene blue (MB) from environmental water samples prior to UV-Vis spectrophotometry. Molecular imprinted polymer sorbents were synthesized using radical polymerization by MB, 4-vinylpyridine, ethylene-glycol-dimethacrylate, 2,2′-azobisisobutyronitrile and methanol as a template, functional monomer, cross-linker, initiator, and porogen, respectively. The imprinted polymer was characterized by Fourier transform infrared spectroscopy and scanning electron microscopy. The pH, adsorbent mass, adsorption time, eluent volume, and extraction time were been selected as input parameters and the recovery of MB was considered as an output variable of the ANN model. The results were then compared according to the performance function and determination coefficient. The Freundlich and Langmuir adsorption models were used to explain the isotherm constant. The maximum adsorption capacity was 417 mg g-1. At the optimized conditions, the limit of detection and relative standard deviation was found to be 0.31 μg l-1 and <1.7%, respectively. This method was applied to analysis the MB in various water samples.

Recovery and separation of erythromycin from industrial wastewater by imprinted magnetic nanoparticles that exploit β-cyclodextrin as the functional monomer

A type of surface imprinting over magnetic Fe3 O4 nanoparticles utilizing erythromycin-A as a template for use in the separation and recovery of erythromycin was developed and investigated. As the intermolecular forces play a key role in the performance of imprinted materials, differential scanning calorimetry, and (1) H NMR spectroscopy was employed to evaluate the interactions between erythromycin and the functional monomer β-cyclodextrin. To synthesize the surface imprinted polymers, magnetic Fe3 O4 nanoparticles, the core materials, were modified with a free radical initiator to initialize polymerization in a "grafting from" manner. Then using acryloyl-modified β-cyclodextrin as the functional monomer and ethyleneglycol dimethacrylate as the cross-linker, thin erythromycin-imprinted films were fabricated by the radical-induced graft copolymerization of monomers on the surface of the Fe3 O4 nanoparticles. Selectivity experiments showed that the erythromycin-A-imprinted materials had recognition ability toward erythromycin derivatives. Finally, these magnetic molecularly imprinted particles were successfully used for the separation and enrichment of erythromycin from the mother liquor. The recovery, detected by high-performance liquid chromatography and differential pulse voltammetry, approached 97%. The combination of the specific selectivity of the imprinted material and the magnetic separation provided a powerful tool that is simple, flexible, and selective for the separation and recovery of erythromycin.