An Encyclopedic Compendium on Chemosensing Supramolecular Metal-Organic Gels

Chemosensing, an interdisciplinary scientific domain, plays a pivotal role ranging from environmental monitoring to healthcare diagnostics and (inter)national security. Metal-organic gels (MOGs) are recognized for their stability, selectivity, and responsiveness, making them valuable for chemosensing applications. Researchers have explored the development of MOGs based on different metal ions and ligands, allowing for tailored properties and sensitivities, and have even demonstrated their applications as portable sensors such as paper-based test strips for practical use. Herein, several studies related to MOGs development and their applications in the chemosensing field via UV-visible or luminance along with electrochemical approach are presented. These papers explored MOGs as versatile materials with their use in sensing bio or environmental analytes. This review provides a foundational understanding of key concepts, methodologies, and recent advancements in this field, fostering the scientific community.

A Water-Soluble Polyacid Polymer Based on Hydrophilic Metal-Organic Frameworks Using Amphoteric Carboxylic Acid Ligands as Linkers for Hydroxycamptothecin Loading and Release In Vitro

The poor water solubility and severe side effects of hydroxycamptothecin (HCPT) limit its clinical application; therefore, it is necessary to synthesize applicable nanodrug carriers with good solubility to expand the applications of HCPT. In this study, a hydrophilic metal-organic framework (MOF) with amphoteric carboxylic acid ligands as linkers was first synthesized and characterized. Then, water-soluble acrylamide and methacrylic acid were applied as monomers to prepare a water-soluble polyacid polymer MOF@P, which had a solubility of 370 μg/mL. The effects of the MOF@P material on the HCPT loading and solubility were investigated. The results showed that the polymer material could improve the HCPT solubility in water. Moreover, the in vitro release study indicated that the MOF@P polymeric composite exhibited a sustained-release effect on HCPT, with a cumulative release rate of 30.18% in 72 h at pH 7.4. Furthermore, the cytotoxicity test demonstrated that the hydrophilic MOF and the MOF@P had low cell toxicities. The results indicate that the prepared MOF@P polymeric complex can be applied for the sustained release of HCPT in clinics.

Metal-Organic Gel-Modulated Synthesis of Hierarchically Porous Molecularly Imprinted Polymers for Efficient Removal of Sildenafil from Water

Molecularly imprinted polymers (MIPs) with high specific recognition capability are promising in environmental remediation. However, traditional MIPs usually show poor specific binding affinity toward templates in pure aqueous medium, thus greatly limiting their practical applications in wastewater treatment. Herein, we proposed a facile and versatile method to synthesize a water-compatible hierarchically porous MIP (HP-MIP), in which a metal-organic gel (MOG) was formed by in situ assembly and acted as a removable structural modulator. Remarkably, the integration of the MOG modulator and template imprinting defects significantly improved the specific template binding affinity of HP-MIP in water. The adsorption behavior of HP-MIP fitted well with the heterogeneous Freundlich isotherm, suggesting that HP-MIP possessed greater site heterogeneity to sildenafil than HP-NIP, which confirmed the efficiency of HP-MIP for the removal of sildenafil from water. This approach provides an important pathway to prepare water-compatible porous MIP for efficient removal of highly toxic organic pollutants from wastewater.

Molecularly Imprinted Polymers Doped with Carbon Nanotube with Aid of Metal-Organic Gel for Drug Delivery Systems

PURPOSE

The incidence of breast cancer worldwide has been on the rise since the late 1970s, and it has become a common tumor that threatens women's health. Aminoglutethimide (AG) is a common treatment of breast cancer. However, current treatments require frequent dosing that results in unstable plasma concentration and low bioavailability, risking serious adverse reactions. Our goal was to develop a molecularly imprinted polymer (MIP) based delivery system to control the release of AG and demonstrate the availability of this drug delivery system (DDS), which was doped with carbon nanotube with aid of metal-organic gel.

METHODS

Preparation of MIP was optimized by key factors including composition of formula, ratio of monomers and drug loading concentration.

RESULTS

By using multi-walled carbon nanotubes (MWCNT) and metal-organic gels (MOGs), MIP doubled the specific surface area, pore volume tripled and the IF was 1.6 times than the reference. Compared with commercial tablets, the relative bioavailability was 143.3% and a more stable release appeared.

CONCLUSIONS

The results highlight the influence of MWCNT and MOGs on MIP, which has great potential as a DDS.

Molecular imprinted polymers for the controlled uptake of sinapic acid from aqueous media

Molecularly imprinted polymers (MIPs) were synthesized via a precipitation polymerization method using 4-vinylpyridine as a functional monomer and ethylene glycol dimethacrylate as a cross-linker for selective separation of sinapic acid from water.

Hydrophilic surface molecularly imprinted naringin prepared via reverse atom transfer radical polymerization with excellent recognition ability in a pure aqueous phase

An easy and highly efficient method using hydrophilic surface molecularly imprinted polymers (SMIPs) for the selective recognition of naringin from pure aqueous solution was developed.

pH/temperature-sensitive hydrogel-based molecularly imprinted polymers (hydroMIPs) for drug delivery by frontal polymerization

Frontal polymerization was successfully utilized, for the first time, to obtain pH/temperature-sensitive hydrogel-based molecularly imprinted polymers (hydroMIPs).