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.     

Pharmacological Activities of Soursop (Annona muricata Lin.)

Soursop (Annona muricata Lin.) is a plant belonging to the Annonaceae family that has been widely used globally as a traditional medicine for many diseases. In this review, we discuss the traditional use, chemical content, and pharmacological activities of A.muricata. From 49 research articles that were obtained from 1981 to 2021, A.muricata’s activities were shown to include anticancer (25%), antiulcer (17%), antidiabetic (14%), antiprotozoal (10%), antidiarrhea (8%), antibacterial (8%), antiviral (8%), antihypertensive (6%), and wound healing (4%). Several biological activities and the general mechanisms underlying the effects of A.muricata have been tested both in vitro and in vivo. A.muricata contains chemicals such as acetogenins (annomuricins and annonacin), alkaloids (coreximine and reticuline), flavonoids (quercetin), and vitamins, which are predicted to be responsible for the biological activity of A. muricata.     

Molecular Dynamic Study of Mechanism Underlying Nature of Molecular Recognition and the Role of Crosslinker in the Synthesis of Salmeterol-Targeting Molecularly Imprinted Polymer for Analysis of Salmeterol Xinafoate in Biological Fluid

The rational preparation of molecularly imprinted polymers (MIPs) in order to have selective extraction of salmeterol xinafoate (SLX) from serum was studied. SLX is an acting β-adrenergic receptor agonist used in the treatment of asthma and has an athletic performance-enhancing effect. Molecular dynamics were used for the simulation of the SLX-imprinted pre-polymerization system, to determine the stability of the system. The computational simulation showed that SLX as a template, 4-hydroxyethyl methacrylate (HEMA) as a monomer, and trimethylolpropane trimethacrylate (TRIM) as a crosslinker in mol ratio of 1:6:20 had the strongest interaction in terms of the radial distribution functional. To validate the computational result, four polymers were synthesized using the precipitation polymerization method, and MIP with composition and ratio corresponding with the system with the strongest interaction as an MD simulation result showed the best performance, with a recovery of 96.59 ± 2.24% of SLX in spiked serum and 92.25 ± 1.12% when SLX was spiked with another analogue structure. Compared with the standard solid phase extraction sorbent C-18, which had a recovery of 79.11 ± 2.96%, the MIP showed better performance. The harmony between the simulation and experimental results illustrates that the molecular dynamic simulations had a significant role in the study and development of the MIPs for analysis of SLX in biological fluid.     

Rational design of salmeterol xinafoate imprinted polymer through computational method: Functional monomer and crosslinker selection

A molecular imprinted polymer (MIP) was computationally designed and synthesized for the selective extraction of salmeterol xinafoate (SLX) from human serum. In this study, semi-empirical PM3 calculations were used to find a suitable functional monomer (FM), the ratio of template (T) to FM, and types of crosslinkers. MIPs were synthesized with 2-hydroxyethyl methacrylate (HEMA) with T:FM mol ratios of 1:6 and 1:4 and ethylene glycol dimethacrylate (EGDMA) or trimethylolpropane trimethacrylate (TRIM) as a crosslinker. On the basis of computational and experimental results, HEMA and TRIM in the mol ratio 1:6 of T-FM (MIP3) were found to be the best choices of FM and crosslinker, respectively. These polymers were then used as a selective sorbent to develop a molecularly imprinted solid-phase extraction procedure followed by high performance liquid chromatography with UV detection for the determination of SLX in serum. The extraction ability of MIP3 was excellent with a recovery of 92.17% ± 2.66% of SLX in spiked serum, and 91.15% ± 1.12% when SLX was spiked as a mixture with another analogous structure. By comparing the performance of the synthesized sorbent with a C-18 cartridge with a recovery of 79.11% ± 2.96%, it was determined that MIP had better performance over the latter. On the basis of these results, the imprinted receptor MIPs, especially MIP 3, can be applied for the direct extraction of SLX in clinical analysis.     

An Update on the Use of Molecularly Imprinted Polymers in Beta-Blocker Drug Analysis as a Selective Separation Method in Biological and Environmental Analysis

Beta-blockers are antihypertensive drugs and can be abused by athletes in some sport competitions; it is therefore necessary to monitor beta-blocker levels in biological samples. In addition, beta-blocker levels in environmental samples need to be monitored to determine whether there are contaminants from the activities of the pharmaceutical industry. Several extraction methods have been developed to separate beta-blocker drugs in a sample, one of which is molecularly imprinted polymer solid-phase extraction (MIP-SPE). MIPs have some advantages, including good selectivity, high affinity, ease of synthesis, and low cost. This review provides an overview of the polymerization methods for synthesizing MIPs of beta-blocker groups. The methods that are still widely used to synthesize MIPs for beta-blockers are the bulk polymerization method and the precipitation polymerization method. MIPs for beta-blockers still need further development, especially since many types of beta-blockers have not been used as templates in the MIP synthesis process and modification of the MIP sorbent is required, to obtain high throughput analysis.