How Does the Powder Mixture of Ibuprofen and Caffeine Attenuate the Solubility of Ibuprofen? Comparative Study for the Xanthine Derivatives to Recognize Their Intermolecular Interactions Using Fourier-Transform Infrared (FTIR) Spectra, Differential Scanning Calorimetry (DSC), and X-ray Powder Diffractometry (XRPD).

Molecular interactions between active pharmaceutical ingredients (APIs) and xanthine (XAT) derivatives were analyzed using singular value decomposition (SVD). XAT derivatives were mixed with equimolar amounts of ibuprofen (IBP) and diclofenac (DCF), and their dissolution behaviors were measured using high-performance liquid chromatography. The solubility of IBP decreased in mixtures with caffeine (CFN) and theophylline (TPH), whereas that of DCF increased in mixtures with CFN and TPH. No significant differences were observed between the mixtures of theobromine (TBR) or XAT with IBP and DCF. Mixtures with various molar ratios were analyzed using differential scanning calorimetry, X-ray powder diffraction, and Fourier-transform infrared spectroscopy to further explore these interactions. The results were subjected to SVD. This analysis provides valuable insights into the differences in interaction strength and predicted interaction sites between XAT derivatives and APIs based on the combinations that form mixtures. The results also showed the impact of the XAT derivatives on the dissolution behavior of IBP and DCF. Although IBP and DCF were found to form intermolecular interactions with CFN and TPH, these effects resulted in a reduction of the solubility of IBP and an increase in the solubility of DCF. The current approach has the potential to predict various interactions that may occur in different combinations, thereby contributing to a better understanding of the impact of health supplements on pharmaceuticals.

Postsynthetically Modified Cationic, Robust MOF Featuring Selective Separation of Carboxylate-Containing Pharmaceutical Drugs from Water at Neutral pH: Elucidation of the Adsorption Mechanism by Theory and Experiments.

The escalating levels of hazardous pharmaceutical contaminants, specifically nonsteroidal anti-inflammatory drugs (NSAIDs), in groundwater reservoir surfaces and surface waterway systems have prompted substantial scientific interest regarding their potential deleterious effects on both aquatic ecosystems and human health. Extraction of those pollutants from wastewater is quite challenging. Hence, the development of economic, sustainable, and scalable techniques for capturing and removing those pollutants is crucial to ensure water safety. Herein, we demonstrate a physicochemically stable, reusable, porous Hf(IV)-based cationic metal-organic framework (MOF), namely, 1'@MeCl for the aqueous phase adsorption-based removal of NSAIDs (diclofenac, naproxen, ibuprofen) from the wastewater environment. The highly positively charged surface of the 1'@MeCl MOF enables it to selectively extract more than 99% of diclofenac, naproxen, and ibuprofen contaminants within less than 30 s. With fast adsorption kinetics, very high adsorption capacities (Qe) were achieved at neutral pH for diclofenac (482.9 mg/g), naproxen (295.9 mg/g), and ibuprofen (219.5 mg/g). Moreover, the influence of changes in pH and coexisting anions on the adsorption property of the 1'@MeCl MOF was studied. Furthermore, the adsorption efficiency of 1'@MeCl in different real water environments was ensured by performing diclofenac, naproxen, and ibuprofen adsorption from tap, river, and lake water. Moreover, a 1'@MeCl-anchored cellulose acetate-chitosan membrane was developed successfully to demonstrate the membrane-based extraction of diclofenac, naproxen, and ibuprofen from contaminated water. Furthermore, a molecular-level mechanistic study was performed through experimental and computational study to propose the plausible adsorption mechanisms for diclofenac, naproxen, and ibuprofen over the surface of 1'@MeCl.

Semirational Design Strategy To Enhance the Thermostability and Catalytic Activity of Cytochrome P450 105D7 for the Degradation of the Pharmaceutically Active Compounds: Diclofenac.

Pharmaceutically active compounds are an important category of emerging pollutants, and their biological transformation processes in the environment are crucial for understanding and evaluating the migration, transformation, and environmental fate of emerging pollutants. The cytochrome P450 105 enzyme family has been proven to play an important role in the degradation of exogenous environmental pollutants. However, its thermostability and catalytic activity still need to be improved to better adapt to complex environmental conditions. This work elucidates the key mechanisms and important residues of the degradation reaction through multiple computational strategies, establishes a mutation library, and obtains 21 single-point mutation designs. Experimental verification showed that 16 single mutants had enhanced thermostability, with the R89F and L197Y mutants showing the highest increases in thermostability at 135 and 119% relative to the wild-type enzyme, respectively. Additionally, as a result of the higher specific activity of D390Q, it was selected for combination mutagenesis, ultimately resulting in three combination mutants (R89F/L197Y, R89F/D390Q, and R89F/L197Y/D390Q) with enhanced thermostability and catalytic activity. This study provides a modification approach for constructing efficient enzyme variants through semirational design and can contribute to the development of control technologies for emerging pollutants.

New Insights into the Role of Humic Acid in Permanganate Oxidation of Diclofenac: A Novel Electron Transfer Mechanism.

Humic acid (HA) ubiquitously existing in aquatic environments has been reported to significantly impact permanganate (KMnO4) decontamination processes. However, the underlying mechanism of the KMnO4/HA system remained elusive. In this study, an enhancing effect of HA on the KMnO4 oxidation of diclofenac (DCF) was observed over a wide solution pH range of 5-9. Surprisingly, the mechanism of HA-induced enhancement varied with solution pH. Quenching and chemical probing experiments revealed that manganese intermediates (Mn(III)-HA and MnO2) were responsible for the enhancement under acidic conditions but not under neutral and alkaline conditions. By combining KMnO4 decomposition, galvanic oxidation process experiments, electrochemical tests, and FTIR and XPS analysis, it was interestingly found that HA could effectively mediate the electron transfer from DCF to KMnO4 in neutral and alkaline solutions, which was reported for the first time. The formation of an organic-catalyst complex (i.e., HA-DCF) with lower reduction potential than the parent DCF was proposed to be responsible for the accelerated electron transfer from DCF to KMnO4. This electron transfer likely occurred within the complex molecule formed through the interaction between HA-DCF and KMnO4 (i.e., HA-DCF-KMnO4). These results will help us gain a more comprehensive understanding of the role of HA in the KMnO4 oxidation processes.

New Perspectives on the Interactions between Adsorption and Degradation of Organic Micropollutants in Granular Activated Carbon Filters.

The removal of organic micropollutants in granular activated carbon (GAC) filters can be attributed to adsorption and biological degradation. These two processes can interact with each other or proceed independently. To illustrate the differences in their interaction, three 14C-labeled organic micropollutants with varying potentials for adsorption and biodegradation were selected to study their adsorption and biodegradation in columns with adsorbing (GAC) and non-adsorbing (sand) filter media. Using 14CO2 formation as a marker for biodegradation, we demonstrated that the biodegradation of poorly adsorbing N-nitrosodimethylamine (NDMA) was more sensitive to changes in the empty bed contact time (EBCT) compared with that of moderately adsorbing diclofenac. Further, diclofenac that had adsorbed under anoxic conditions could be degraded when molecular oxygen became available, and substantial biodegradation (≥60%) of diclofenac could be achieved with a 15 min EBCT in the GAC filter. These findings suggest that the retention of micropollutants in GAC filters, by prolonging the micropollutant residence time through adsorption, can enable longer time periods for degradations than what the hydraulic retention time would allow for. For the biologically recalcitrant compound carbamazepine, differences in breakthrough between the 14C-labeled and nonradiolabeled compounds revealed a substantial retention via successive adsorption-desorption, which could pose a potential challenge in the interpretation of GAC filter performance.

H*ads dynamics engineering via bimetallic Pd-Cu@MXene catalyst for enhanced electrocatalytic hydrodechlorination.

Electrocatalytic hydrodechlorination (EHDC) is a promising approach to safely remove halogenated emerging contaminants (HECs) pollutants. However, sluggish production dynamics of adsorbed atomic H (H*ads) limit the applicability of this green process. In this study, bimetallic Pd-Cu@MXene catalysts were synthesized to achieve highly efficient removal of HECs. The alloy electrode (Pd-Cu@MX/CC) exhibited better EHDC performance in comparison to Pd@MX/CC electrode, resulting in diclofenac degradation efficiency of 93.3 ± 0.1%. The characterization analysis revealed that the Pd0/PdII ratio decreased by forming bimetallic Pd-Cu alloy. Density functional theory calculations further demonstrated the electronic configuration modulation of the Pd-Cu@MXene catalysts, optimizing binging energies for H* and thereby facilitating H*ads production and tuning the reduction capability of H*ads. Noteably, the amounts and reduction potential of H*ads for Pd-Cu@MXene catalysts were 1.5 times higher and 0.37 eV lower than those observed for the mono Pd electrode. Hence, the introduction of Cu into the Pd catalyst optimized the dynamics of H*ads production, thereby conferring significant advantages to EHDC reactions. This augmentation was underscored by the successful application of the alloy catalysts supported by MXene in EHDC experiments involving other HECs, which represented a new paradigm for EHDC for efficient recalcitrant pollutant removal by H*ads.

Synthesis of sustainable mesoporous sulfur-doped biobased carbon with superior performance sodium diclofenac removal: Kinetic, equilibrium, thermodynamic and mechanism.

Over the last years, the strategy of employing inevitable organic waste and residue streams to produce valuable and greener materials for a wide range of applications has been proven an efficient and suitable approach. In this research, sulfur-doped porous biochar was produced through a single-step pyrolysis of birch waste tree in the presence of zinc chloride as chemical activator. The sulfur doping process led to a remarkable impact on the biochar structure. Moreover, it was shown that sulfur doping also had an important impact on sodium diclofenac (S-DCF) removal from aqueous solutions due to the introduction of S-functionalities on biochar surface. The adsorption experiments suggested that General and Liu models offered the best fit for the kinetic and equilibrium studies, respectively. The results showed that the kinetic was faster for the S-doped biochar while the maximum adsorption capacity values at 318 K were 564 mg g-1 (non-doped) and 693 mg g-1 (S-doped); highlighting the better affinity of S-doped biochar for the S-DCF molecule compared to non-doped biochar. The thermodynamic parameters (ΔH0, ΔS0, ΔG0) suggested that the S-DCF removal on both adsorbents was spontaneous, favourable, and endothermic.

Green synthesis of carbon nanotubes functionalized with iron nanoparticles and coffee husk biomass for efficient removal of losartan and diclofenac: Adsorption kinetics and ANN modeling studies.

The presence of emerging contaminants in wastewater poses a global environmental challenge, requiring the development of innovative materials or methods for their treatment. This study focused on the production of green functionalized carbon nanotubes (CNTs) and using them in the adsorption of the pharmaceuticals Losartan (LOS) and Diclofenac (DIC). The efficiency of the methodology was verified by characterization techniques. Elemental composition analysis indicated a significant increase in the iron content after the green functionalization, proving the effectiveness of the method. Thermogravimetric analysis showed similar thermal degradation profiles for pristine CNTs and functionalized CNTs, indicating better post-functionalization thermal stability. BET analysis revealed mesoporous characteristics of CNTs, with increased surface area and pore volumes after functionalization. X-Ray diffraction confirmed the preservation of the lattice structure of the CNTs post-functionalization and post-adsorption, with changes in peak broadening suggesting surface modifications. LOS and DIC adsorption were evaluated via kinetic studies at four different concentrations (0.1-0.4 mmol/L) that were best represented by the pseudo-second order model, suggesting chemisorption mechanisms, with faster and higher uptakes for DIC (0.084-0.261 mmol/g; teq = 5 min) when compared to LOS (0.058-0.235 mmol/g; teq = 20 min). The curves were also studied via artificial neural networks (ANN) and revealed that the best ANN architecture for representing the experimental data is a network with [3 5 5 2] neurons trained using the Bayesian-Regularization algorithm and the Log-sigmoid (hidden layers) and Linear (output layer) transfer functions. The desorption study showed that CaCl2 had better performance in CNT regeneration, reaching its removal capacity above 50% up to 3 cycles, for both pharmaceuticals. These findings reveal the potential of the developed material as a promising adsorbent for targeted removal of pollutants, contributing to advances in the remediation of emerging contaminants and the application of artificial intelligence in adsorption research.

Periodate activation and pH regulation using ball-milled metal-oxide-mineral-biochar composite for removal of antibiotics from contaminated water.

The inclusion of mineral salts in carbon activators are beneficial for advanced oxidation processes (AOPs). Herein, we present the application of ball-milled biochar with phosphate salt for periodate (IO4-) activation and degradation of antibiotics in contaminated water. Physical characterization results showed that the catalyst is infused with Mg3(PO4)2 and ball-milling increased the specific surface area to 216 m2 g-1 from 46 m2 g-1 while reducing the particle size to less than 1.0 µ. The optimized system successfully eliminated >99% of diclofenac while maintaining the pH of the reaction medium to circumneutral levels. Scavenger and ESR experiments revealed the degradation is triggered by O2•-, 1O2 and •OH species within the system. Electrochemical studies confirmed electron transfer during diclofenac degradation. The reported system demonstrated high degradation efficiency under both neutral and acidic pH conditions. Based on the by-product analysis, the degradation pathway of diclofenac was elucidated. Further, the toxicity assessment for the identified intermediates showed minimum toxicity of the degraded products. This mineral-biochar composite exhibited promising performance in eliminating other antibiotic substances. Therefore, the present finding highlights the importance of raw materials selection for producing mineral-biochar composite that provide new insights into IO4- activation for antibiotic removal by maintaining the natural pH.

A novel and sustainable composite of L@PSAC for superior removal of pharmaceuticals from different water matrices: Production, characterization, and application.

This study endeavors to develop cost-effective environmentally friendly technology for removing harmful residual pharmaceuticals from water and wastewater by utilizing the effective adsorption of pistachio shell (PS) biochar and the degradation potency of laccase immobilized on the biochar (L@PSAC). The carbonatization and activation of the shells were optimized regarding temperature, time, and NH4NO3/PS ratio. This step yielded an optimum PS biochar (PSAC) with the highest porosity and surface area treated at 700 °C for 3 h using an NH4NO3/PS ratio of 3% wt. The immobilization of laccase onto PSAC (L@PSAC) was at its best level at pH 5, 60 U/g, and 30 °C. The optimum L@PSAC maintained a high level of enzyme activity over two months. Almost a complete removal (>99%) of diclofenac, carbamazepine, and ciprofloxacin in Milli-Q (MQ) water and wastewater was achieved. Adsorption was responsible for >80% of the removal and the rest was facilitated by laccase degradation. L@PSAC maintained effective removal of pharmaceuticals of ≥60% for up to six treatment cycles underscoring the promising application of this material for wastewater treatment. These results indicate that activated carbon derived from the pistachio shell could potentially be utilized as a carrier and adsorbent to efficiently remove pharmaceutical compounds. This enzymatic physical elimination approach has the potential to be used on a large-scale.

Influence of Endogenous Substances on Site-II to Site-I Displacement of Diclofenac Bound to Albumin in the Aqueous Humor of Patients with Cataract.

Diclofenac instillation is useful in preventing intraoperative miosis and macular edema caused by postoperative inflammation in cataract surgery; however, optimum efficacy is not attained when the instilled diclofenac strongly binds to albumin in patients' aqueous humor. Therefore, a method that inhibits diclofenac binding and increases the concentration of its free fraction is needed. We conducted a basic study regarding the effects of inhibitors on the binding of instilled diclofenac to albumin and endogenous substances in aqueous humor. Aqueous humor samples from 16 patients were pooled together for analysis. The free fraction of diclofenac was measured using ultrafiltration methods in various experiments with pooled and mimic aqueous humor. Free fraction of diclofenac, a site II drug, in pooled aqueous humor was 0.363 ± 0.013. The binding of diclofenac in the presence of phenylbutazone (PB), a site I inhibitor, was significantly inhibited (free fraction = 0.496 ± 0.013); however, no significant inhibition by ibuprofen, a site II inhibitor, (free fraction = 0.379 ± 0.004), was observed. The unexpected result was due to free fatty acids (FFAs; palmitic acid (PA)) and L-tryptophan (Trp). The inhibition of diclofenac binding by PB in the mimic aqueous humor containing these endogenous substances revealed significant binding inhibition in the presence of PA and Trp. Diclofenac is strongly rebound from site II to site I in the presence of FFAs and Trp in the aqueous humor because FFAs and Trp induce a conformational change in albumin. Therefore, PB significantly inhibits the binding of diclofenac to albumin.

Pharmaceutically active compounds removal from aqueous solutions by MIL-101(Cr)-NH2: A molecular dynamics study.

Discharging pharmaceutically active drugs into water and wastewater has become a significant environmental threat. Traditional methods are unable to effectively remove these compounds from wastewater, so it is necessary to search for more effective methods. This study investigates the potential of MIL-101(Cr)-NH2 as a preferable and more effective adsorbent for the adsorption and removal of pharmaceutically active compounds from aqueous solutions. By utilizing its large porosity, high specific surface area, and high stability, the structural and transport properties of three pharmaceutically active compounds naproxen (NAP), diclofenac (DIC) and sulfamethoxazole (SMX)) studied using molecular dynamics simulation. The results indicate that the MIL-101(Cr)-NH2 adsorbent is suitable for removing drug molecules from aqueous solutions, with maximum adsorption capacities of 697.75 mg/g for naproxen, 704.99 mg/g for diclofenac, and 725.51 mg/g for sulfamethoxazole.

Diclofenac sodium adsorption on activated carbon: experimental, modeling and bayesian statistics.

The present study modeled the adsorption process of the drug diclofenac sodium on activated charcoal. For this purpose, a mass balance-based model was used considering a fixed bed column. The mass transfer rate in the solid phase was represented by a driving force model proposed in this study, and a gamma exponent with a range of 0 > γ ≤ 2 was assigned to the model. Different isotherms were adopted to represent the equilibrium at the solid/liquid interface: the Langmuir, Freundlich, Sips and Redlich-Peterson isotherms. The modeling was approached from the perspective of Bayesian statistics, and the Markov chain Monte Carlo method was used for parameter estimation. Model validation was performed with experimental data obtained under different operating conditions of initial concentration ($C_{0.

Alternatives to Conventional Topical Dosage Forms for Targeted Skin Penetration of Diclofenac Sodium.

Skin penetration of an active pharmaceutical ingredient is key to developing topical drugs. This penetration can be adjusted for greater efficacy and/or safety through the selection of dosage form. Two emerging dosage forms, cream-gel and gel-in-oil emulsion, were tested for their ability to deliver diclofenac into the skin, with the target of maximising skin retention while limiting systemic exposure. Prototypes with varying amounts of solvents and emollients were formulated and evaluated by in vitro penetration testing on human skin. Cream-gel formulas showed better skin penetration than the emulgel benchmark drug even without added solvent, while gel-in-oil emulsions resulted in reduced diffusion of the active into the receptor fluid. Adding propylene glycol and diethylene glycol monoethyl ether as penetration enhancers resulted in different diclofenac penetration profiles depending on the dosage form and whether they were added to the disperse or continuous phase. Rheological characterisation of the prototypes revealed similar profiles of cream-gel and emulgel benchmark, whereas gel-in-oil emulsion demonstrated flow characteristics suitable for massaging product into the skin. This study underlined the potential of cream-gel and gel-in-oil emulsions for adjusting active penetration into the skin, broadening the range of choices available to topical formulation scientists.

Efficient low-strength diclofenac elimination via adsorption-concentration and peroxydisulfate activation mineralization by distinct pretreated biocarbon composites.

Sodium diclofenac (DCF) widely exists in actual water matrices, which can negatively impact ecosystems and aquatic environments even at low-strength. Herein, the adsorption-concentration-mineralization process was innovatively constructed for low-strength DCF elimination by freeze-dried biocarbon and oven-dried biocarbon coupled with cobalt oxide composites derived from the same waste biomass. Surprisingly, low-strength DCF of 0.5 mg/L was adsorbed rapidly and enriched to high-strength DCF under light with a concentration efficiency of 99.67 % by freeze-dried biocarbon. Subsequently, the concentrated DCF was economically mineralized by bifunctional oven-dried biocarbon coupled with cobalt oxide composites for peroxydisulfate (PDS) activation with full PDS activation and 76.11 % mineralization efficiency. Compared with direct low-strength DCF oxidation, adsorption-concentration-mineralization consumed less energy and none PDS residues. Mechanisms confirmed that DCF was adsorbed by freeze-dried biocarbon through hydrogen bonds and π-π stacking interactions, which were switched on due to electron-induced effect by light in DCF desorption-concentration. Furthermore, nonradical pathway (electron transfer) and radical pathway (SO4•-) were involved in efficient PDS activation by oven-dried biocarbon coupled with cobalt oxide composites for concentrated DCF mineralization, and the former was more prominent, in which graphitic carbon, cobalt redox cycle and carboxy groups were the main active sites. Overall, an energy-efficient strategy was proposed for elimination of low-strength DCF in real water matrices.

Biosorption Ability of Pharmaceutically Active Compounds by Anabaena sp. and Chroococcidiopsis thermalis.

Drug overuse harms the biosphere, leading to disturbances in ecosystems' functioning. Consequently, more and more actions are being taken to minimise the harmful impact of xenopharmaceuticals on the environment. One of the innovative solutions is using biosorbents-natural materials such as cells or biopolymers-to remove environmental pollutants; however, this focuses mainly on the removal of metal ions and colourants. Therefore, this study investigated the biosorption ability of selected pharmaceuticals-paracetamol, diclofenac, and ibuprofen-by the biomass of the cyanobacteria Anabaena sp. and Chroococcidiopsis thermalis, using the LC-MS/MS technique. The viability of the cyanobacteria was assessed by determining photosynthetic pigments in cells using a UV-VIS spectrophotometer. The results indicate that both tested species can be effective biosorbents for paracetamol and diclofenac. At the same time, the tested compounds did not have a toxic effect on the tested cyanobacterial species and, in some cases, stimulated their cell growth. Furthermore, the Anabaena sp. can effectively biotransform DCF into its dimer.

Behavior of diclofenac from contaminated fish after cooking and in vitro digestion.

BACKGROUND: Seafood consumers are widely exposed to diclofenac due to the high contamination levels often present in aquatic organisms. It is a potential risk to public health due its endocrine disruptor properties. Limited information is available about diclofenac behavior after food digestion to enable a more realistic scenario of consumer exposure. This study aimed to evaluate cooking effects on diclofenac levels, and determine diclofenac bioaccessibility by an in vitro digestion assay, using commercial fish species (seabass and white mullet) as models. The production of the main metabolite 4'-hydroxydiclofenac was also investigated. Fish hamburgers were spiked at two levels (150 and 1000 ng g-1) and submitted to three culinary treatments (roasting, steaming and grilling). RESULTS: The loss of water seems to increase the diclofenac levels after cooking, except in seabass with higher levels. The high bioaccessibility of diclofenac (59.1-98.3%) observed in both fish species indicates that consumers' intestines are more susceptible to absorption, which can be worrisome depending on the level of contamination. Contamination levels did not affect the diclofenac bioaccessibility in both species. Seabass, the fattest species, exhibited a higher bioaccessibility of diclofenac compared to white mullet. Overall, cooking decreased diclofenac bioaccessibility by up to 40% in seabass and 25% in white mullet. The main metabolite 4'-hydroxydiclofenac was not detected after cooking or digestion. CONCLUSION: Thus, consumption of cooked fish, preferentially grilled seabass and steamed or baked white mullet are more advisable. This study highlights the importance to consider bioaccessibility and cooking in hazard characterization studies. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Effect of Fluid Paraffin on the Formulation Properties of Pressure Sensitive Adhesive Formulations Containing Diclofenac Sodium.

Understanding the relationship between the release characteristics of the active ingredient in the tape formulation and the pharmaceutical characteristics of the adhesive layer can optimize therapeutic efficacy and improve patient adherence. This study aimed to clarify the effect of liquid paraffine (LP)/styrene-isoprene-styrene (SIS) triblock copolymer ratio on pressure-sensitive adhesive (PSA) formulation properties, such as adhesive properties and drug release, with a certain amount of diclofenac sodium (DFS) and tackifier. The effects of changes in PSA composition in DFS-containing tape formulations on adhesive and drug release properties were evaluated. The viscoelasticity results showed rigid gel-like behavior at low angular frequencies regardless of the LP/SIS ratio, and deformable gel-like behavior at high angular frequencies, with a maximum plasticizing effect of LP up to an LP/SIS ratio of 3.7. The peel adhesion test results showed that peel adhesion was not affected, but indicated a decreasing trend by increasing the LP/SIS ratio in the presence of DFS. Drug release test results showed that DFS release increased up to 24 h for LP/SIS ratios of up to 3.7, but decreased when the LP/SIS ratio was 6. The results of the drug permeation tests were similar to those of the drug release tests. In conclusion, it is possible to change the drug release properties by changing the amount of LP in the tape formulation; however, no definitive correlation was found between the adhesive and drug release properties.

Potassium permanganate-modified eggshell biosorbent for the removal of diclofenac from liquid environment: adsorption performance, isotherm, kinetic, and thermodynamic analyses.

This study assess how well diclofenac (DCF) can be separated from aqueous solution using potassium permanganate-modified eggshell biosorbent (MEB). The MEB produced was characterised using XRD, FTIR, and SEM. Batch experiments were conducted to examine and assess the impact of contact time, adsorbent dosage, initial concentration, and temperature on the adsorption capacity of the MEB in the DCF sequestration. The best parameters to obtained 95.64% DCF removal from liquid environment were 0.05 g MEB weight, 50 mg/L initial concentration, and 60 min contact time at room temperature. The maximum DCF sequestration capacity was found to be 159.57 mg/g with 0.05 g of MEB at 298 K. The adsorption isotherm data were more accurately predicted by the Freundlich model, indicating a process of heterogeneous multilayer adsorption. The results of the kinetic study indicated that the pseudo-second-order kinetic models best matched the experimental data. The findings revealed that the dynamic of DCF entrapment is largely chemisorption and diffusion controlled. Based on the values of thermodynamic parameters, the process is both spontaneous and endothermic. The primary processes of DCF sorption mechanism onto the MEB were chemical surface complexation, hydrogen bonding, π-π stacking, and electrostatic interactions. The produced MEB showed effective DCF separation from the aqueous solution and continued to have maximal adsorption capability even after five regeneration cycles. These findings suggest that MEB could be highly efficient adsorbent for the removal of DCF from pharmaceutical wastewater.

Bifunctional catalytic degradation of diclofenac over Cu-Pd co-modified sponge iron-based trimetal: Parameter optimization.

Currently, the pharmaceutical and personal care products (PPCPs) have posed great challenge to advanced oxidation techniques (AOTs). In this study, we decorated sponge iron (s-Fe0) with Cu and Pd (s-Fe0-Cu-Pd) and further optimized the synthesis parameters with a response surface method (RSM) to rapidly degrade diclofenac sodium (DCF). Under the RSM-optimized conditions of Fe: Cu: Pd = 100: 4.23: 0.10, initial solution pH of 5.13, and input dosage of 38.8 g/L, 99% removal of DCF could be obtained after 60 min of reaction. Moreover, the morphological structure of trimetal was characterized with high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM), X-ray diffraction (XRD), X-ray photoelectron spectra (XPS). Electron spin resonance (ESR) signals have also been applied to capture reactive hydrogen atoms (H*), superoxygen anions, hydroxyl radicals, and single state oxygen (1O2). Furthermore, the variations of DCF and its selective degradation products over a series of s-Fe0-based bi(tri)metals have been compared. Additionally, the degradation mechanism of DCF has also been explored. To our best knowledge, this is the first report revealing the selective dechlorination of DCF with low toxicity over Pd-Cu co-doped s-Fe0 trimetal.