Adsorptive removal of ibuprofen to binary and amine-functionalized UiO-66 in the aquatic environment: synergistic/antagonistic evaluation

Review on the utilization of metal organic frameworks (MOFs) for eliminating ibuprofen and naproxen from water sources

The increasing concern regarding pharmaceutical contaminants in the environment, particularly ibuprofen (IBU) and naproxen (NPX), has led to extensive research on effective methods for removing these pollutants. This review evaluates the use of metal organic frameworks (MOFs) for the removal of IBU and NPX from water, summarizing findings from studies published between 2010 and 2024, sourced from Google Scholar, ScienceDirect, and Scopus. The analysis shows that 68.3% of the reviewed studies focused on IBU and 31.7% on NPX. Analytical techniques such as XRD, FESEM, FTIR, XPS and BET were frequently used, appearing in 95.12, 78, 75.6, 56.1%, and 34.15% of the studies, respectively. This study demonstrated that MOFs, including Pd@MIL-100(Fe), UiO-67@β-CD-NP, HSO₃-MIL-53(Fe), and UiO-66-MOF, are capable of achieving complete removal of the targeted pharmaceuticals. The findings indicate that the key factors influencing removal efficiency include solution pH, MOF dosage, and adsorption mechanisms. This review concludes that MOFs, particularly those following the Langmuir adsorption isotherm model and PSO adsorption kinetics, are promising for the effective removal of IBU and NPX. These results highlight the potential of MOFs in addressing pharmaceutical contamination and suggest further research, particularly in optimizing MOF structures for environmental applications.

Photo-enhanced UiO-66/Au Nanoparticles with High Phosphatase-Like Activity for Rapid Degradation and Detection of Paraoxon

The severe environmental and human health hazards posed by organophosphorus compounds underscore the pressing need for advancements in their degradation and detection. However, practical implementation is impeded by prolonged degradation durations and limited efficiency. Herein, an effective interfacial modification approach is proposed involving the integration of photoactive Au nanoparticles (NPs) onto metal-organic frameworks, resulting in the synthesis of UiO-66/Au NPs exhibiting enhanced hydrolysis activity under light excitation. Under illumination, UiO-66/Au NPs trigger rapid hydrolysis of ethyl-paraoxon within a mere 10-min timeframe, yielding a discernible colorimetric response indicative of extensive hydrolysis. Mechanistic analyses reveal that Au NPs elevate the local catalytic microenvironment temperature of UiO-66/Au NPs under light exposure, facilitating photo-induced charge transfer that enhances the affinity between the Zr6 clusters within UiO-66/Au NPs and the hydrolytic substrate. These cooperative mechanisms significantly boost the hydrolytic efficiency of UiO-66/Au NPs, resulting in a remarkable 17.8-fold enhancement in catalytic performance. Leveraging the superior photo-enhanced hydrolytic capabilities of UiO-66/Au NPs, a colorimetric sensor is developed for the rapid degradation and detection of ethyl-paraoxon, offering a practical and effective solution for addressing the degradation and detection challenges associated with organophosphorus compounds.

Highly Dispersive Gold Nanoclusters Confined within Micropores of Defective UiO-66 for Highly Efficient Aldehyde Oxidation at Mild Conditions

The oxidative esterification of aldehydes under mild conditions remains a significant challenge. This study introduces a unique defective UiO-66 to achieve gold nanoclusters (AuNCs) for efficient aldehyde oxidation under mild conditions. The construction and characterization of these materials are thoroughly investigated by techniques of XRD, SEM and TEM images, FT-IR, Raman, and XPS spectrum, emphasizing the unique microporous in defective UiO-66 are conducive to the fabrication of AuNCs. The catalytic performance of the prepared materials in aldehyde oxidation reactions is systematically evaluated, demonstrating the remarkable efficiency of dispersed Au@UiO-66-25 with high-content (9.09 wt%) Au-loading and ultra-small size (~2.7 nm). Moreover, mechanistic insights into the catalytic process under mild conditions (70 °C for 1 h) are provided, elucidating the determination of defective UiO-66 in the confined fabrication of AuNCs and subsequent furfural adsorption, which underlie the principles governing the observed enhancements. This study establishes the groundwork for the synthesis of highly dispersed and catalytically active metal nanoparticles using defective MOFs as a platform, advancing the catalytic esterification reaction of furfural to the next level.

Hybrid chitosan/molecularly imprinted polymer hydrogel beads doped with iron for selective ibuprofen adsorption

Pharmaceutical pollutants are a group of emerging contaminants frequently found in water streams. In this study, the composite chitosan beads with incorporated molecularly imprinted polymers (monoliths or microparticles) and iron(III) hydroxide were fabricated to remove ibuprofen from aqueous solutions. The adsorptive properties were investigated in different conditions to evaluate the influence of solution pH, adsorbent dose, ibuprofen initial concentration, adsorption time, and temperature. The highest adsorption capacity (79.41 mg g-1), about twice as large as that for the chitosan beads without polymers (39.42 mg g-1), was obtained for the ones containing monoliths imprinted with ibuprofen. The theoretical maximum adsorption capacity of 103.93 mg g-1 was obtained based on the experiments in optimal pH 5. The adsorption of ibuprofen on the hybrid hydrogel beads followed the Freundlich isotherm and pseudo-second-order kinetic models. The process was found as endothermic and thermodynamically spontaneous. The adsorbent with a molecularly imprinted polymer retained its selectivity in the presence of other molecules. The imprinted cavities, chitosan functional groups, and iron hydroxide were presumably responsible for interactions with ibuprofen molecules. Additionally, the effectiveness of the adsorbent did not change significantly in real water samples and remained at a satisfactory level for up to four desorption-adsorption cycles.

Fabricating modified carbon sesame straw for adsorption of acetaminophen and ibuprofen from aqueous media: isotherm and kinetic models

As acetaminophen (ACT) and ibuprofen (IBP) have serious environmental impacts, despite their widespread use in many countries, the present research examined the effectiveness of activated carbon made from straw and sesame stubble in removing ACT and IBP from water. To that end, the as-synthesized adsorbent was functionalized using zinc chloride. The maximum adsorption capacities were found to be 51.7 mg g-1 for ACT and 63.7 mg g-1 for IBP. The adsorption kinetics and isotherm results showed that the pseudo-second-order (PSO) kinetics and Langmuir isotherm fit the data obtained from this study better than the other experimental models do. Also, the adsorption reached equilibrium within 120 min, and the optimal adsorbent dose and temperature were obtained as 1.0 mg and 25 °C, respectively. The mechanisms involved in the adsorption process would include acid-base, hydrogen bonding, electrostatic forces, and π-π interaction. Reusability studies revealed that the adsorbent still preserved about 89% and 82% of the adsorption performance for ACT and IBP, respectively, after seven repeated adsorption cycles. As the findings indicated, CSS/Zn could be accepted as a hopeful adsorbent to be used in pharmaceutical treatment.

Performance of Zr-Based Metal-Organic Framework Materials as In Vitro Systems for the Oral Delivery of Captopril and Ibuprofen

Zr-based metal-organic framework materials (Zr-MOFs) with increased specific surface area and pore volume were obtained using chemical (two materials, Zr-MOF1 and Zr-MOF3) and solvothermal (Zr-MOF2) synthesis methods and investigated via FT-IR spectroscopy, TGA, SANS, PXRD, and SEM methods. The difference between Zr-MOF1 and Zr-MOF3 lies in the addition of reactants during synthesis. Nitrogen porosimetry data indicated the presence of pores with average dimensions of ~4 nm; using SANS, the average size of the Zr-MOF nanocrystals was suggested to be approximately 30 nm. The patterns obtained through PXRD were characterized by similar features that point to well-crystallized phases specific for the UIO-66 type materials; SEM also revealed that the materials were composed of small and agglomerate crystals. Thermogravimetric analysis revealed that both materials had approximately two linker deficiencies per Zr6 formula unit. Captopril and ibuprofen loading and release experiments in different buffered solutions were performed using the obtained Zr-based metal-organic frameworks as drug carriers envisaged for controlled drug release. The carriers demonstrated enhanced drug-loading capacity and showed relatively good results in drug delivery. The cumulative percentage of drug release in phosphate-buffered solution at pH 7.4 was higher than that in buffered solution at pH 1.2. The release rate could be controlled by changing the pH of the releasing solution. Different captopril release behaviors were observed when the experiments were performed using a permeable dialysis membrane.