Development of 2-(dimethylamino)ethyl methacrylate-based molecular recognition devices for controlled drug delivery using supercritical fluid technology

Unveiling the potential of molecular imprinting polymer-based composites in the discovery of advanced drug delivery carriers

Molecularly imprinted polymers (MIPs) are polymeric matrices that can mimic natural recognition entities, such as antibodies and biological receptors. Molecular imprinting of therapeutics is very appealing in the design of drug delivery systems since the specific and selective binding sites created within the polymeric matrix turn these complex structures into value-added carriers with tunable features, notably high drug-loading capacity and good control of payload release. MIPs possess considerable promise as synthetic recognition elements in 'theranostics'. Moreover, the high affinity and specificity of MIPs make them more advantageous than other polymer-based nanocomposites. This review summarizes the present state-of-the-art of MIP-based delivery systems for the targeted delivery of bioactives, with current challenges and future perspectives.

Molecularly Imprinted Drug Carrier for Lamotrigine-Design, Synthesis, and Characterization of Physicochemical Parameters

This study presents the initial attempt at introducing a magnetic molecularly imprinted polymer (MIP) designed specifically for lamotrigine with the purpose of functioning as a drug carrier. First, the composition of the magnetic polymer underwent optimization based on bulk polymer adsorption studies and theoretical analyses. The magnetic MIP was synthesized from itaconic acid and ethylene glycol dimethacrylate exhibiting a drug loading capacity of 3.4 ± 0.9 μg g-1. Structural characterization was performed using powder X-ray diffraction analysis, vibrating sample magnetometry, and Fourier transform infrared spectroscopy. The resulting MIP demonstrated controlled drug released characteristics without a burst effect in the phospahe buffer saline at pH 5 and 8. These findings hold promise for the potential nasal administration of lamotrigine in future applications.

A ratiometric fluorescence imprinted sensor based on N-CDs and metal-organic frameworks for visual smart detection of malathion

Sensitive and rapid detection of pesticide residues in food is essential for human safety. A ratiometric imprinted fluorescence sensor N-CDs@Eu-MOF@MIP (BR@MIP) was constructed to sensitively detect malathion (Mal). Europium-based metal organic frameworks (Eu-MOF) were used as supporters to improve the sensitivity of the BR@MIP. N-doped carbon dots (N-CDs) were used as fluorescent source to produce fluorescent signal. A linear relationship between the concentration of Mal and the fluorescence response of the sensor was found in the Mal concentration range of 1-10 μM with a limit of detection (LOD) of 0.05 μM. Furthermore, the sensor was successfully applied for the detection of Mal in lettuce, tap water, and soil samples, with recoveries in the range of 93.0 % - 99.3 %. Additionally, smartphone-based sensors were used to detect Mal in simulated real samples. Thus, the construction of ratiometric imprinted fluorescence sensor has provided a good strategy for the detection of Mal.

Design of Molecularly Imprinted Polymers Using Supercritical Carbon Dioxide Technology

The design and development of affinity polymeric materials through the use of green technology, such as supercritical carbon dioxide (scCO2), is a rapidly evolving field of research with vast applications across diverse areas, including analytical chemistry, pharmaceuticals, biomedicine, energy, food, and environmental remediation. These affinity polymeric materials are specifically engineered to interact with target molecules, demonstrating high affinity and selectivity. The unique properties of scCO2, which present both liquid- and gas-like properties and an accessible critical point, offer an environmentally-friendly and highly efficient technology for the synthesis and processing of polymers. The design and the synthesis of affinity polymeric materials in scCO2 involve several strategies. Commonly, the incorporation of functional groups or ligands into the polymer matrix allows for selective interactions with target compounds. The choice of monomer type, ligands, and synthesis conditions are key parameters of material performance in terms of both affinity and selectivity. In addition, molecular imprinting allied with co-polymerization and surface modification are commonly used in these strategies, enhancing the materials' performance and versatility. This review aims to provide an overview of the key strategies and recent advancements in the design of affinity polymeric materials using scCO2.

Novel dual-emission fluorescence imprinted sensor based on Mg, N-CDs and metal-organic frameworks for rapid and smart detection of 2, 4, 6-trinitrophenol

Rapid and real-time detection of 2, 4, 6-trinitrophenol (TNP) is of great importance for the living environment and human health. Herein, we constructed an innovative ratiometric fluorescence imprinted sensor with fast response and high selectivity based on magnesium and nitrogen co-doped carbon dots (Mg, N-CDs) and chromium telluride quantum dots (r-CdTe) self-assembled in zirconium-based metal organic frameworks (UiO-66) combined with imprinted polymers for the detection of TNP. In the protocol, the introduction of UiO-66 with large specific surface area and porosity using as carrier material significantly enhanced the mass transfer rate, which improved the sensitivity of the Mg, N-CDs/r-CdTe@UiO-66@MIP (LHU@MIP). And the Mg, N-CDs with high quantum yields and r-CdTe were selected as fluorescence emitting elements to yield fluorescence signal, achieving signal amplification. The dual-channel strategy enabled the sensor to not only display a fast fluorescence response, but also generate a dual-response signal under the action of internal filtering effect (IFE). Combining these advantages, the LHU@MIP had a wide linear range (1-100 μM), good detection sensitivity (0.56 μM), and a distinct color change (from blue to pink). Meanwhile, for accurate on-site analysis, we designed a portable smart sensing platform with a color recognizer application. The smartphone enabled visual sensing of TNP by capturing fluorescent images and converting them into digital values. More importantly, the platform was successfully utilized for the analysis of TNP in the simulated actual samples with considerable results. Therefore, the developed platform was characterized by low cost, portability, ideal specificity, and provided a strategy for on-site monitoring of TNP.

Molecularly Imprinted Carriers for Diagnostics and Therapy-A Critical Appraisal

Simultaneous diagnostics and targeted therapy provide a theranostic approach, an instrument of personalized medicine-one of the most-promising trends in current medicine. Except for the appropriate drug used during the treatment, a strong focus is put on the development of effective drug carriers. Among the various materials applied in the production of drug carriers, molecularly imprinted polymers (MIPs) are one of the candidates with great potential for use in theranostics. MIP properties such as chemical and thermal stability, together with capability to integrate with other materials are important in the case of diagnostics and therapy. Moreover, the MIP specificity, which is important for targeted drug delivery and bioimaging of particular cells, is a result of the preparation process, conducted in the presence of the template molecule, which often is the same as the target compound. This review focused on the application of MIPs in theranostics. As a an introduction, the current trends in theranostics are described prior to the characterization of the concept of molecular imprinting technology. Next, a detailed discussion of the construction strategies of MIPs for diagnostics and therapy according to targeting and theranostic approaches is provided. Finally, frontiers and future prospects are presented, stating the direction for further development of this class of materials.

Role of molecularly imprinted hydrogels in drug delivery - A current perspective

Molecular imprinting in hydrogels crafts memory for template molecules in a flexible macromolecular structure. Molecular imprinting can control the pattern of the drug release via different mechanistic pathways which may involve swelling, which releases the drug via diffusion or receptive-swollen networks. Responsive hydrogels or smart hydrogels can be tailored to undergo a change in the network structure in response to a stimulus by inserting specific chemical or biological entities along their backbone polymer chains. The stimuli which can be either physical, chemical or biochemical in nature, may impact at various energy levels thereby initiating the molecular interactions at critical onset points. Conventional hydrogels lack in responding to an external stimuli in a swift manner, hence the molecular imprinting technology can significantly advance the therapeutic efficiency of the drugs with anticipated controlled release and targeting efficiency. Molecular imprinting in hydrogels is thus anticipated as a step towards establishment of drug delivery systems by providing improved delivery profiles or longer release times and deliver the drugs in a feedback regulated way. The review article focuses on the current scenario of molecularly imprinted hydrogels with emphasis on the imprinting strategies within hydrogels and challenges encountered, latent translational applications, and future perspectives.

Molecularly Imprinted Polymers for Cell Recognition

Since their conception 50 years ago, molecularly imprinted polymers (MIPs) have seen extensive development both in terms of synthetic routes and applications. Cells are perhaps the most challenging target for molecular imprinting. Although early work was based almost entirely around microprinting methods, recent developments have shifted towards epitope imprinting to generate MIP nanoparticles (NPs). Simultaneously, the development of techniques such as solid phase MIP synthesis has solved many historic issues of MIP production. This review briefly describes various approaches used in cell imprinting with a focus on applications of the created materials in imaging, drug delivery, diagnostics, and tissue engineering.

Some Advances in Supercritical Fluid Extraction for Fuels, Bio-Materials and Purification

Supercritical fluids are used for the extraction of desired ingredients from natural materials, but also for the removal of undesired and harmful ingredients. In this paper, the pertinent physical and chemical properties of supercritical water, methanol, ethanol, carbon dioxide, and their mixtures are provided. The methodologies used with supercritical fluid extraction are briefly dealt with. Advances in the application of supercritical extraction to fuels, the gaining of antioxidants and other useful items from biomass, the removal of undesired ingredients or contaminants, and the preparation of nanosized particles of drugs are described.

Green Strategies for Molecularly Imprinted Polymer Development

Molecular imprinting is a powerful technology to create artificial receptors within polymeric matrices. Although it was reported for the first time by Polyakov, eighty-four years ago, it remains, nowadays, a very challenging research area. Molecularly imprinted polymers (MIPs) have been successfully used in several applications where selective binding is a requirement, such as immunoassays, affinity separation, sensors, and catalysis. Conventional methods used on MIP production still use large amounts of organic solvents which, allied with stricter legislation on the use and release of chemicals to the environment and the presence of impurities on final materials, will boost, in our opinion, the use of new cleaner synthetic strategies, in particular, with the application of the principles of green chemistry and engineering. Supercritical carbon dioxide, microwave, ionic liquids, and ultrasound technology are some of the green strategies which have already been applied in MIP production. These strategies can improve MIP properties, such as controlled morphology, homogeneity of the binding sites, and the absence of organic solvents. This review intends to give examples reported in literature on green approaches to MIP development, from nano- to micron-scale applications.

Development of itaconic acid-based molecular imprinted polymers using supercritical fluid technology for pH-triggered drug delivery

A novel pH-responsive molecularly imprinted polymer (MIP) based on Itaconic acid:Ethylene glycol dimethacrylate was developed as a potential body-friendly oral drug delivery system for metronidazole (MZ), a pH-independent drug. MIP performance was evaluated in a simulated oral administration situation, at pHs 2.2 and 7.4. Itaconic acid-based copolymers were synthesized using two different molar ratios of template:monomer:crosslinker (T:M:C), 1:5:25 and 1:5:50, in supercritical carbon dioxide (scCO₂) in high yields. Further, impregnation of MZ was performed in scCO₂ environment. Morphological and chemical properties of the copolymers produced were assessed by SEM, Morphologi G3 and FTIR analyses. Non-molecularly imprinted polymer (NIP) matrices presented swelling over time in opposition to the molecularly imprinted ones. In the scCO₂-impregnation process, MIPs showed a significant molecular recognition towards MZ, presenting higher drug uptake ability with MZ loading of 18-61 wt% in MIPs, compared to 7-20 wt% in NIPs. In vitro drug release experiments presented different release profiles at the different pHs, where MZ-MIPs could release higher amounts of MZ at the lowest pH than at pH 7.4.

Controlled release of mitomycin C from PHEMAH-Cu(II) cryogel membranes

Molecular imprinting technique was used for the preparation of antibiotic and anti-neoplastic chemotherapy drug (mitomycin C) imprinted cryogel membranes (MMC-ICM). The membranes were synthezied by using metal ion coordination interactions with N-methacryloyl-(l)-histidine methyl ester (MAH) functional monomer and template molecules (i.e. MMC). The 2-hydroxyethyl methacrylate (HEMA) monomer and methylene bisacrylamide (MBAAm) crosslinker were used for the preparation of mitomycin C imprinted cryogel membranes by radical suspension polymerization technique. The imprinted cryogel membranes were characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), Fourier transform infrared spectroscopy-attenuated total reflectance (FTIR-ATR) and swelling degree measurements. Cytotoxicity of MMC-ICMs was investigated using mouse fibroblast cell line L929. Time-dependent release of MMC was demonstrated within 150 h from cryogel membranes. Cryogels demonstrated very high MMC loading efficiency (70-80%) and sustained MMC release over hours.

Molecularly imprinted polymers based drug delivery devices: a way to application in modern pharmacotherapy. A review

This review presents the current status of molecularly imprinted polymers (MIPs) for drug delivery, in particular the studies that focus on biocompatibility, cytotoxicity, and in vitro or in vivo behavior of MIPs. It also shows the limitations that hamper the introduction of MIPs to pharmacotherapy and prevent this class of polymers from commercialization. MIPs are promising materials in the construction of drug delivery devices because they can provide improved delivery profiles or longer release times and deliver the drugs in the feedback regulated way, which is extremely important in modern pharmacotherapy. Here, a brief overview of the imprinting process and a concise description of drug release mechanisms from the imprinted materials will be presented followed by the discussion of potential MIP drug delivery devices for ocular, dermal, intravenous and oral routes of administration. Finally, future prospects for imprinted drug delivery forms will be outlined.

5-Fluorouracil delivery from metal-ion mediated molecularly imprinted cryogel discs

The objective of this study is to prepare imprinted cryogel discs for delivery of 5-fluorouracil. The coordinate bond interactions are utilized to accomplish a coordination complex between metal-chelate monomer N-methacryloyl-L-histidine and 5-FU with the assistance of Cu(2+) ion. The complex is copolymerized with hydroxyethyl methacrylate to produce poly(hydroxyethyl methacrylate-N-methacryloyl-(L)-histidine methyl ester) cryogel discs. The cryogel discs are characterized thoroughly by performing swelling tests, scanning electron microscopy, differential scanning calorimetry and X-ray diffraction studies. In vitro delivery studies are performed to investigate the effects of cross-linker ratio, medium pH and drug concentration. 5-FU imprinted cryogel discs have highly macroporous structures. Drug molecules are homogeneously dispersed in the 5-FU imprinted cryogel matrix. The cumulative release of 5-FU decreased by increasing the cross-linker density in the polymer matrix. Delivery rate of 5-FU varied with different pH values in a coordination complex since metal ion acts as a Lewis acid, and the ligand, i.e. 5-FU acts as a Lewis base. The cumulative release of 5-FU increased with increasing drug concentration in polymer matrix. The nature of the 5-FU transport mechanism is non-Fickian.

Mesoporous molecularly imprinted polymer nanoparticles as a sustained release system of azithromycin

A combination of a molecular imprinting technique and precipitation polymerization was applied to develop novel azithromycin-imprinted poly(methacrylic acid-co-ethylene glycol dimethacrylate) nanoparticles for sustained release of azithromycin (AZM).

Molecular imprinting science and technology: a survey of the literature for the years 2004-2011

Herein, we present a survey of the literature covering the development of molecular imprinting science and technology over the years 2004-2011. In total, 3779 references to the original papers, reviews, edited volumes and monographs from this period are included, along with recently identified uncited materials from prior to 2004, which were omitted in the first instalment of this series covering the years 1930-2003. In the presentation of the assembled references, a section presenting reviews and monographs covering the area is followed by sections describing fundamental aspects of molecular imprinting including the development of novel polymer formats. Thereafter, literature describing efforts to apply these polymeric materials to a range of application areas is presented. Current trends and areas of rapid development are discussed.

Critical gases for critical issues: CO2 technologies for oral drug delivery

In recent years, CO2-based technologies have gained considerable interest in the pharmaceutical industry for their potential applications in drug formulation and drug delivery. The exploitation of peculiar properties of gases under supercritical conditions has been studied in the last 20 years with mixed results. Promising drug-delivery technologies, based on supercritical CO2, have mostly failed when facing challenges of industrial scaleability and economical viability. Nevertheless, a ‘second generation‘ of processes, based on CO2 around and below critical point has been developed, possibly offering technology-based solutions to some of the current issues of pharmaceutical development. In this review, we highlight the most recent advancements in this field, with a particular focus on the potential of CO2-based technologies in addressing critical issues in oral delivery, and briefly discuss the future perspectives of dense CO2-assisted processes as enabling technologies in drug delivery.

Supercritical CO2-assisted synthesis of an ultrasensitive amphibious quantum dot-molecularly imprinted sensor

A green supercritical CO₂-assisted molecular imprinting protocol enabled the production of smart sensory particles, incorporating quantum dots, with molecular recognition to bisphenol A at very low concentrations (4 nM).

A NEW SIMPLE CORRELATION FOR CALCULATING SOLUBILITY OF DRUGS IN SUPERCRITICAL CARBON DIOXIDE

During the past 20 years, supercritical fluid (SCF) based technologies have been gaining an increasing attention through the academic and industrial communities due to its advantages. One of the most important parameter for any supercritical-based technologies is the knowledge of the solute solubility at different pressures and temperatures. But, due to several concerns e.g. time and expense, measuring the solubility of all compounds in wide ranges of temperature and pressure is not possible. Respect to this, a new empirical correlation with four fitting parameters has been proposed to correlate the solubility of pharmaceuticals in different temperatures and pressures. The obtained results compared with four widely used density based correlations including Mendez-Santiago and Teja (MST), Bartle et al., Chrastil, Kumar and Johnston (KJ) revealed rather good capability of the proposed simple correlation for predicting the solubility of solutes in supercritical carbon dioxide (SC- CO 2). At last, the obtained results compared with the results of three Equations of State (EoS's) with three different mixing rules.