新型分子印迹聚合物共混膜的制备进展

本文总结了近年来分子印迹聚合物膜的研究状况,详述了分子印迹共混膜的制备进展,并简要概括了其在药物分离、传输等领域的应用。     

表面印迹聚合物的制备及其在药物分离分析中的应用

表面分子印迹技术是在载体表面上发生聚合反应,将分子识别位点建立在载体的外层或者表面。从而使表面分子印迹聚合物具有结合速度快、识别选择性强、结合容量高、提高印迹材料的效率等优点。近年来表面分子印迹技术在药物分离分析中的应用引起人们的关注。简要介绍了表面分子印迹聚合物的原理及4种制备方法(溶胶-凝胶法、接枝共聚法、牺牲载体法、聚合加膜法、活性可控自由基聚合法),并对其在药物分离分析的4个方面(中药提取分离中;药物传感器方面;手性药物拆分中;药物释放中)的应用进行了综述。     

分子印迹聚合物的设计与制备

对分子印迹聚合物的设计、制备及其特性以及分子印迹技术的未来发展方向进行简要评述。过程及方法：概述了分子印迹技术的原理和特点，重点介绍了分子印迹聚合物的制备和特性，最后分析了分子印迹技术目前存在的一些突出问题。结果及应用范围：作为一种制备具有亲和性和选择性高、稳定性好的分子印迹聚合物的技术，分子印迹以其简便、通用和高效等特点吸引了研究者的广泛兴趣。分子印迹聚合物在分离分析、仿生传感器和模拟酶催化等领域将具有重要的应用前景。     

磁性分子印迹聚合物微球的应用研究进展

将磁性分离技术与分子印迹技术相结合,制备磁性分子印迹聚合物(MMIPMs),该复合材料兼具良好的超顺磁性和高选择吸附性两大优点,具有广阔的应用前景。文章重点综述了磁性分子印迹聚合物微球在食品检测、医药领域、手性药物拆分、生物分离和环境检测方面的应用进展,并指出未来发展方向。     

分子印迹聚合物结合与识别能力的影响因素

分子印迹技术是近年来迅速发展起来的一种分子识别技术,被应用于色谱分离、固相萃取、药物分析、环境监测、仿生传感器、催化等领域.结合与识别能力是分子印迹聚合物的重要性能,详细分析了分子印迹聚合物结合与识别能力的影响因素.     

基于壳聚糖的分子印迹技术研究及应用

分子印迹技术是一种新兴的分子识别技术,该技术可以制备具有特异选择性识别能力的聚合物,凭借其高度的专一性、稳定性以及可重复性等特点,逐渐成为了研究热点。壳聚糖是一种环境友好、来源丰富且可循环再生的天然高分子化合物,其分子结构中的氨基等官能团具有较强的活性,使壳聚糖具有生物降解性、细胞亲和性和生物效应等多种独特的性质,在医学、食品、环保等领域广泛应用。壳聚糖的官能团反应活性强,易进行改性或化学修饰,因此以壳聚糖及其衍生物为功能单体或载体,结合分子印迹技术,易制备具有理想的亲和性和稳定性、高印迹效率、强选择性的新型分子印迹聚合物,从而提高壳聚糖材料的性能,拓宽其应用领域和范围。本文根据近年来国内外学者在壳聚糖分子印迹改性领域的研究进展,对壳聚糖及其衍生物在分子印迹聚合物制备中的作用、分子印迹聚合物制备方法以及常用交联剂的类型进行总结,详细阐述了壳聚糖分子印迹聚合物在重金属污染物处理、生物医学、固相萃取、蛋白质识别、电化学传感器、手性物质分离等方面的应用,分析了壳聚糖分子印迹聚合物在各领域应用的优缺点,并展望了壳聚糖分子印迹技术的发展方向。     

分子印迹填充色谱柱用于药物分离的研究进展

分子印迹聚合物(MIP)是由模板分子与功能单体相互作用,然后在合适的条件下加入交联剂聚合而成的一种高分子材料.将该聚合物装填高效液相色谱(HPLC)固定相,可利用其印迹空穴中的特异性识别位点,实现模板分子和竞争分子间的分离.综述了近年来分子印迹填充色谱柱的发展状况、合成方法与袁征手段.重点论述对分子印迹填充色谱柱分离效果和印迹效果产生影响的重要因素,指出模板分子的选择、填料的表面结构以及色谱条件对分离有较大影响.最后,对分子印迹色谱柱在药物分离领域的发展前景进行展望,提出了不足之处.     

分子印迹聚合物及其复合材料在法医学领域中的研究进展

分子印迹聚合物拥有特定的印迹位点,在结构和功能上与模板匹配,具有高特异性、高稳定性和可重复使用等优势,越来越引起关注。分子印迹聚合物及其复合材料在环境检测、食品安全和法医学等领域有着广泛的应用,如样品前处理、分离纯化和传感。为了解分子印迹聚合物及其复合材料在法医学领域中的研究现状,综述了分子印迹聚合物的基本材料、制备方法以及分子印聚合物在法医学领域取得的最新进展,并对其研究方向进行展望。     

分子印迹聚合物微球制备方法研究进展

分子印迹聚合物微球具有制备简单、使用方便、分子识别效率高且便于控制粒径大小和功能设计等优点，近年来成为分子印迹技术领域研究的热点之一。对分子印迹聚合物微球的制备方法：溶胀悬浮聚合法、沉淀聚合法、悬浮聚合法和表面聚合法及其最新研究进展作了较为详细的综述。     

磁性纳米分子印迹聚合物的制备及其在食品安全检测中的应用研究

磁性纳米材料作为一种新型的高分子材料,具有比表面积大、可进行表面修饰以及在外加磁场作用下易于从复杂基质中分离的特性。分子印迹技术(MIT)是通过模拟抗原-抗体结合原理制备出具有预定性、稳定性以及特异性识别聚合物的方法。以磁性纳米材料制备的分子印迹聚合物,由于具有高效、高选择性,近年来在食品分析领域的应用备受关注。综述了磁性纳米分子印迹聚合物(MMIPs)的制备方法及其在食品安全检测中的应用。     

分子印迹聚合物在分离领域的应用

分子印迹技术是近年来集高分子合成、分子设计、分子识别、仿生生物工程等众多学科优势发展起来的一种应用广泛的新型技术.阐述了分子印迹方法的基本原理,介绍了分子印迹聚合物在分离领域的应用.综述了该技术的研究现状,并展望了其发展趋势.     

Development of a pH-responsive imprinted polymer for diclofenac and study of its binding properties in organic and aqueous media

Three different molecularly imprinted polymers (MIPs) for drug delivery of diclofenac in gastrointestinal tract were synthesized employing bulk polymerization method and their binding and release properties were studied in different pH values. Methacrylic acid (MAA), methacrylamide (MAAM) and 4-vinyl pyridine (4VP) were tested as functional monomers and ethylene glycole dimethacrylate (EDMA) was used as a cross-linker monomer in polymeric feed. Binding properties and imprinting factor (IF) of MIPs were studied in comparison with their non-imprinted ones (Blank) in organic and aqueous media. Diclofenac release in aqueous solvents at pH values of 1.5, 6.0 and 8.0, simulating gastrointestinal fluids, were also studied. The results indicated the specific binding of diclofenac to imprinted polymers. Duo to the stronger non-specific bounds in aqueous solutions, IF values decreased in water compared to acetonitrile as an organic medium. Our results proved that all polymers represented pH-responsive diclofenac delivery at above conditions. The data showed that imprinted polymer, prepared by MAA had superior properties, in comparison with other polymers, for minimum release (14%) of drug in gastric acid and maximum release (90%) in basic condition. The results indicated that diclofenac imprinted polymer could be used as a pH-responsive matrix in preparation of a new drug delivery system for diclofenac.     

Characterization of the imprint effect and the influence of imprinting conditions on affinity, capacity, and heterogeneity in molecularly imprinted polymers using the Freundlich isotherm-affinity distribution analysis

Molecularly imprinted polymers (MIPs) have been used in a wide range of analytical applications in particular in chromatography and sensing. However, the binding properties in MIPs are typically measured only in a narrow concentration range, which corresponds to only a subset of the sites in MIPs. This limited analytical window and binding site heterogeneity of MIPs leads to inaccuracies and inconsistencies in the estimation of their binding properties. This has hampered the characterization and optimization of MIPs for analytical applications. In this study, the origins of the molecular imprinting effect were studied using the newly developed Freundlich isotherm-affinity distribution (FIAD) analysis. The analysis is able to readily calculate an affinity distribution for MIPs from the limited analytical window. The FIAD analysis also yields an estimate of number, affinity, and heterogeneity for this subset of binding sites. Consistent with previous studies, MIPs were found to have higher capacities than the corresponding nonimprinted polymers (NIPs). Interestingly, MIPs were also found to be more heterogeneous than NIPs. Examination of variables in the imprinting process including temperature, template concentration, and cross-linking percentages further confirmed these trends. Based on these observations, a model for the imprinting effect was developed. The larger population of high-affinity sites in MIPs appears to arise from a broadening of the heterogeneous distribution. This suggests that noncovalent MIPs may be ill-suited for chromatographic applications and other applications that are detrimentally affected by binding site heterogeneity and better suited to applications that are less affected by heterogeneity such as sensing.     

Polymers for Mucoadhesive Drug Delivery System: A Current Status

To overcome the relatively short gastrointestinal (GI) time and improve localization for oral controlled or sustained release drug delivery systems, bioadhesive polymers that adhere to the mucin/epithelial surface are effective and lead to significant improvement in oral drug delivery. Improvements are also expected for other mucus-covered sites of drug administration. Bioadhesive polymers find application in the eye, nose, and vaginal cavity as well as in the GI tract, including the buccal cavity and rectum. This article lays emphasis mainly on mucoadhesive polymers, their properties, and their applications in buccal, ocular, nasal, and vaginal drug delivery systems with its evaluation methods.     

Polymers for mucoadhesive drug delivery system: a current status

To overcome the relatively short gastrointestinal (GI) time and improve localization for oral controlled or sustained release drug delivery systems, bioadhesive polymers that adhere to the mucin/epithelial surface are effective and lead to significant improvement in oral drug delivery. Improvements are also expected for other mucus-covered sites of drug administration. Bioadhesive polymers find application in the eye, nose, and vaginal cavity as well as in the GI tract, including the buccal cavity and rectum. This article lays emphasis mainly on mucoadhesive polymers, their properties, and their applications in buccal, ocular, nasal, and vaginal drug delivery systems with its evaluation methods.     

Molecularly Imprinted Nanoparticles for Biomedical Applications

Molecularly imprinted polymers (MIPs) are synthetic receptors with tailor-made recognition sites for target molecules. Their high affinity and selectivity, excellent stability, easy preparation, and low cost make them promising substitutes to biological receptors in many applications where molecular recognition is important. In particular, spherical MIP nanoparticles (or nanoMIPs) with diameters typically below 200 nm have drawn great attention because of their high surface-area-to-volume ratio, easy removal of templates, rapid binding kinetics, good dispersion and handling ability, undemanding functionalization and surface modification, and their high compatibility with various nanodevices and in vivo biomedical applications. Recent years have witnessed significant progress made in the preparation of advanced functional nanoMIPs, which has eventually led to the rapid expansion of the MIP applications from the traditional separation and catalysis fields to the burgeoning biomedical areas. Here, a comprehensive overview of key recent advances made in the preparation of nanoMIPs and their important biomedical applications (including immunoassays, drug delivery, bioimaging, and biomimetic nanomedicine) is presented. The pros and cons of each synthetic strategy for nanoMIPs and their biomedical applications are discussed and the present challenges and future perspectives of the biomedical applications of nanoMIPs are also highlighted.     

Synthesis and characterization of paclitaxel-imprinted nanoparticles for recognition and controlled release of an anticancer drug

Imprinted nanoparticles as drug delivery carriers have been considered because owing to their cross-linked network, they act as the drug reservoir for controlled release. In this study, selective MIPs nanoparticles of paclitaxel (PTX) were successfully developed for application in the biological molecular recognition and in the design of new anticancer drug delivery systems. The MIPs nanoparticles prepared by miniemulsion polymerization technique using methacrylic acid (MAA) and methyl methacrylate as non-covalent functional monomer, ethylene glycol dimethacrylate and trimethylolpropane trimethacrylate (TRIM) as cross-linker agent, azobisisobutyronitrile as initiator, and hexadecane as hydrophobic agent. In order to prepare of MIP nanoparticles, the synthesis conditions and effective parameters, such as: cross-linker agent, different molar ratios of template–functional monomer–cross-linker agent, were investigated. In addition, the effect of different molar ratios of template and monomers on polymers binding and morphology were characterized. Structure and thermal properties of MIPs were confirmed by FT-IR spectroscopy and thermogravimetric analysis. Imprinted nanoparticles showed significant drug loading and encapsulation efficiency, 17.8 and 100 %, respectively. The particle size of MIP nanoparticles varies between 187 and 726 nm, according the SEM images and laser light scattering data. The imprinted nanoparticles showed satisfactory affinity (84 %) to PTX with a binding of 12 times higher than non-imprinted nanoparticles in biological samples when MAA and TRIM were used as functional and cross-linker monomer, respectively. Results from release experiments of MIPs showed a very slow and controlled release of PTX which would be helpful for sustained drug delivery.     

Advances in Natural Polymer-Based Transdermal Drug Delivery Systems for Tumor Therapy

As an alternative to traditional oral and intravenous injections with limited efficacy, transdermal drug delivery (TDD) has shown great promise in tumor treatment. Over the past decade, natural polymers have been designed into various nanocarriers due to their excellent biocompatibility, biodegradability, and easy availability, providing more options for TDD. In addition, surface functionalization modification of the rich functional groups of natural polymers, which in turn are developed into targeted and stimulus-responsive functional materials, allows precise delivery of drugs to tumor sites and release of drugs in response to specific stimuli. It not only improves the treatment efficiency of tumor but also reduces the toxic and side effects to normal tissues. Therefore, the development of natural polymer-based TDD (NPTDD) systems has great potential in tumor therapy. In this review, the mechanism of NPTDD systems such as penetration enhancers, nanoparticles, microneedles, hydrogels and nanofibers prepared from hyaluronic acid, chitosan, sodium alginate, cellulose, heparin and protein, and their applications in tumor therapy are overviewed. This review also outlines the future prospects and current challenges of NPTDD systems for local treatment tumors.     

Development of ocular drug delivery systems using molecularly imprinted soft contact lenses

Recently, significant advances have been made in order to optimize drug delivery to ocular tissues. The main problems in ocular drug delivery are poor bioavailability and uncontrollable drug delivery of conventional ophthalmic preparations (e.g. eye drops). Hydrogels have been investigated since 1965 as new ocular drug delivery systems. Increase of hydrogel loading capacity, optimization of drug residence time on the ocular surface and biocompatibility with the eye tissue has been the main focus of previous studies. Molecular imprinting technology provided the opportunity to fulfill the above-mentioned objectives. Molecularly imprinted soft contact lenses (SCLs) have high potentials as novel drug delivery systems for the treatment of eye disorders. This technique is used for the preparation of polymers with specific binding sites for a template molecule. Previous studies indicated that molecular imprinting technology could be successfully applied for the preparation of SCLs as ocular drug delivery systems. Previous research, particularly in vivo studies, demonstrated that molecular imprinting is a versatile and effective method in optimizing the drug release behavior and enhancing the loading capacity of SCLs as new ocular drug delivery systems. This review highlights various potentials of molecularly imprinted contact lenses in enhancing the drug-loading capacity and controlling the drug release, compared to other ocular drug delivery systems. We have also studied the effects of contributing factors such as the type of comonomer, template/functional monomer molar ratio, crosslinker concentration in drug-loading capacity, and the release properties of molecularly imprinted hydrogels.     

Development of a pH-responsive imprinted polymer for diclofenac and study of its binding properties in organic and aqueous media

Three different molecularly imprinted polymers (MIPs) for drug delivery of diclofenac in gastrointestinal tract were synthesized employing bulk polymerization method and their binding and release properties were studied in different pH values. Methacrylic acid (MAA), methacrylamide (MAAM) and 4-vinyl pyridine (4VP) were tested as functional monomers and ethylene glycole dimethacrylate (EDMA) was used as a cross-linker monomer in polymeric feed. Binding properties and imprinting factor (IF) of MIPs were studied in comparison with their non-imprinted ones (Blank) in organic and aqueous media. Diclofenac release in aqueous solvents at pH values of 1.5, 6.0 and 8.0, simulating gastrointestinal fluids, were also studied. The results indicated the specific binding of diclofenac to imprinted polymers. Duo to the stronger non-specific bounds in aqueous solutions, IF values decreased in water compared to acetonitrile as an organic medium. Our results proved that all polymers represented pH-responsive diclofenac delivery at above conditions. The data showed that imprinted polymer, prepared by MAA had superior properties, in comparison with other polymers, for minimum release (14%) of drug in gastric acid and maximum release (90%) in basic condition. The results indicated that diclofenac imprinted polymer could be used as a pH-responsive matrix in preparation of a new drug delivery system for diclofenac.