Diclofenac Research Articles

A Bibliographic Review of Diclofenac Sodium Determination with Electrochemically Modified Sensors in Different Biological, Pharmaceutical, and water Sources

Diclofenac sodium (DS) attracts the interest of researchers because it is one of the most prevalent pharmaceuticals in aqueous matrices and has the potential to harm aquatic life. However, most of the techniques used to analyze it are expensive and require a highly trained professional to perform them. On the other hand, there is the possibility of testing DS with electrochemical sensors. They are currently available for determining contaminants in different samples (tablets, blood, urine), but only a few articles analyze DS in wastewater. This is how the selection of articles for the review was organized by the type of modifier used in the working electrode. In addition, recent improvements in DS detection using electrochemical techniques in pharmaceutical formulations, biological fluids, and environmental materials were provided and discussed, along with a brief description of the results and methods used in the development publications. Keywords: diclofenac sodium, wastewater, modifier, electrochemical detection.. Resumen El diclofenaco sódico (DS) atrae el interés de los investigadores porque es uno de los productos farmacéuticos más presentes en matrices acuosas y tiene el potencial de dañar la vida acuática. Sin embargo, la mayoría de las técnicas utilizadas para analizarlo son costosas y requieren de un profesional altamente capacitado para realizarlas. Por otro lado, existe la posibilidad de probar DS con sensores electroquímicos. Actualmente están disponibles para la determinación del contaminante en diferentes muestras (tabletas, sangre, orina), pero sólo unos pocos artículos analizan el DS en aguas residuales. Es así como la selección de los artículos para la revisión se organizó por el tipo de modificador utilizado en el electrodo de trabajo. Además, se brindaron y discutieron mejoras recientes en la detección de DS mediante técnicas electroquímicas en formulaciones farmacéuticas, fluidos biológicos y materiales ambientales, junto con una breve descripción de los resultados y métodos empleados en las publicaciones de desarrollo. Palabras Clave: Diclofenaco Sódico, Aguas Residuales, Modificador, Detección Electroquímica.

Differentiated adsorption of acetaminophen and diclofenac via alkyl chain-modified quaternized SBA-15: Insights from molecular simulation

The increasing presence of pharmaceuticals and personal care products (PPCPs) in aquatic systems pose significant environmental concerns. This study addresses this issue by synthesizing quaternized mesoporous SBA-15 (QSBA) with varied alkyl chain lengths of C1QSBA, C8QSBA, and C18QSBA. QSBA utilizes dual mechanisms: hydrophobic interactions via the alkyl chain and electrostatic attraction/ion exchange via the ammonium group. Diclofenac (DCF) and acetaminophen (ACT) were selected as target PPCPs due to their contrasting dissociation properties and hydrophobicity, which are the main characteristics of PPCPs. The adsorption of DCF and ACT revealed that longer alkyl chains enhanced the adsorption capacity of ACT through hydrophobic interactions, whereas dissociated DCF (DCF–) adsorption was superior owing to its high hydrophobicity (log Kow = 4.5) and electrostatic attraction. pH levels between 6 and 8 resulted in a high affinity for DCF–. Notably, among the three alkyl chains, only C18QSBA exhibited the most effective adsorption for DCF–. These PPCPs adsorption trends were confirmed through molecular simulations of adsorption under conditions in which competing ions coexisted. The molecular simulations show that while DCF– has lower adsorption energy than Cl−, OH−, and H3O+ ions in QSBA, enhancing its adsorption under various pH conditions. Conversely, ACT exhibits a higher adsorption energy, which reduces its adsorption efficiency. This suggests the potential application of QSBA with long alkyl chains in the treatment of highly hydrophobic and negatively charged PPCPs. Furthermore, this study emphasizes the importance of simulating adsorption under competing ion conditions.

Novel drug-drug co-amorphous systems of olaparib with nonsteroidal anti-inflammatory drugs with improved solubility, physical stability, antitumor activity and pharmacokinetics

Olaparib (OLA), the first FDA-approved PARP inhibitor, has been approved successively for monotherapy or maintenance treatment of ovarian, breast and pancreatic cancer. Unfortunately, the poor solubility and bioavailability of OLA have limited its application. In this study, novel drug-drug co-amorphous systems of OLA with five nonsteroidal anti-inflammatory drugs (NSAIDs), including flurbiprofen (FLU), ketoprofen (KET), ibuprofen (IBU), diclofenac (DIC) or indomethacin (IND), were prepared for improving the aqueous solubility of OLA and achieving combination therapy against ovarian cancer. These new co-amorphous products were confirmed by powder X-ray diffraction, differential scanning calorimetry, and Fourier transform infrared spectroscopy. Five co-amorphous systems were more soluble and released faster than the crystalline OLA in pH 6.8 buffer, and OLA-DIC and OLA-IND showed superior physicochemical stability under accelerated storage conditions. The antitumor activities of OLA-FLU, OLA-KET, OLA-IBU and OLA-DIC against OVCAR3 cell line were approximately increased by 3.5, 2.4, 2.7, and 6.0-fold than that of OLA, respectively. Moreover, pharmacokinetic studies of co-amorphous OLA-DIC in rats revealed that the OLA exhibited 6.14-fold improvement in AUC0-t value compared with crystalline OLA. Therefore, our study suggested that OLA-NSAIDs co-amorphous systems showed the great potentials to improve the solubility, dissolution behaviors, and bio-pharmaceutical performance of OLA.

The ability of UWWTP to remove NSAIDs: Impact on water quality in the Odra River Czech Republic concerning incoming European legislation

Increased consumption of pharmaceuticals has resulted in their detection in wastewater. If wastewater treatment plants (WWTPs) fail to eliminate these substances adequately, they can seep into the environment, posing potential risks. As non-steroidal anti-inflammatory drugs (NSAIDs) belong to the pharmaceuticals most frequently examined in wastewater, this study aimed to monitor wastewater from the municipal wastewater treatment plant in Ostrava (UWWTP) over the course of a year, specifically assessing how the presence of these substances in discharged wastewater could contaminate the Odra River. To further understand the impact of NSAIDs, we evaluated the effectiveness of UWWTP technology in removing the following selected drugs: diclofenac (DCF), ibuprofen (IBU), naproxen (NAP) and ketoprofen (KET) - as well as their main metabolites: 4′-hydroxydiclofenac (hydroxyDCF), carboxyibuprofen (carboxyIBU), desmethylnaproxen (desmethylNAP), and ketoprofen glucuronide (glucuronideKET).Wastewater samples were collected at both the inflow and outflow of the urban wastewater treatment plant (UWWTP) Ostrava from October 2022 to September 2023. The analysis was performed using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). The concentrations of the monitored substances at the UWWTP inflow varied significantly, ranging from 79 ng/L to 112,125 ng/L, with the highest levels detected for ibuprofen (IBU), diclofenac (DCF), and their metabolites. The UWWTP demonstrated impressive treatment efficiency for IBU, exceeding 98%, while for DCF, it ranged between 56% and 87%. Building on these findings, a monitoring campaign was initiated along the Odra River to evaluate the concentrations of IBU and DCF - substances that had not been measured before. Water samples were taken from various locations along the Odra River from October to November 2023 and analyzed using the same methodology as the wastewater samples. The results indicate that, in line with the proposed environmental quality standards (EQS), IBU and DCF do not pose a significant contamination risk to the Odra River.

Characterization of Taro (Colocasia esculenta) stolon polysaccharide and evaluation of its potential as a tablet binder in the formulation of matrix tablet

This investigation focuses on the extraction, characterization, and evaluation of taro (Colocasia esculenta) stolon polysaccharide (TSP) as a tablet binding agent, which is obtained from edible taro stolon. TSP was subjected to phytochemical screening and characterized by FTIR, DSC, TGA, DTA, XRD, particle size, polydispersity index, zeta potential, rheological behavior, and SEM. The tablets prepared with varying concentrations of TSP (2.5 %, 5 %, 7.5 %, and 10 % w/w) and diclofenac sodium (DS) were evaluated and compared with the same concentrations of gum acacia and PVP K-30. The presence of carbohydrates was confirmed by Molisch's test. The FTIR spectra established the compatibility of the drug with excipients. The SEM images revealed asymmetric and elongated particles of TSP powder. The hydration kinetics study showed matrix hydration and water penetration velocity within the range of 0.602–0.753 g/g and 0.112–0.189 cm/g.h, respectively. The tablets showed drug release of >75 % at 45 min. The release-exponent value above 0.89 indicated a super case II drug transport combining matrix erosion and diffusion. Optimum tablet hardness and very low friability, even at 2.5 % binder concentration, suggested the potential application of the novel TSP as a tablet binder in the formulation of the tablets.

Synthesis, characterization, in vitro and in silico studies of N, N-dimethyl phenyl chalcone-Schiff’s base hybrid

Three dissimilar N, N-dimethylphenyl chalcone Schiff's base hybrids (CSBHs) were synthesized and characterized by nuclear magnetic resonance spectroscopy (NMR), Fourier transform infrared (FT-IR) and ultraviolet-visible spectroscopic techniques by the theoretical as well as investigational methods. The molecular weights of the CSBHs were also confirmed by the Electrospray ionization Mass technique. The in vitro antidiabetic, anti-inflammatory and cytotoxicity were tested for the CSBHs using α-amylase inhibitory and protein anti-denaturation methods. The CSBHs showed good antidiabetic and anti-inflammatory activities and the percentage of inhibitions is nearer to standard drugs acarbose and diclofenac sodium. The molecular docking studies for CSBHs were investigated and their docking results are superior and also density functional theory method are performed for CSBHs to support biological and molecular docking results. The CSBHs showed very good hydrogen bonding interactions with amino acid residues of the enzymes and the CSBHs showed lower band gap and higher electrophilicity index values. In addition, (ADMET) Absorption, Distribution, Metabolism, Excretion and Toxicity study and Protox-II toxicity predictions were performed to check the pharmacological properties of CSBHs.

Pyrazole-based N-phenyl pyrazolines: Synthesis, docking, and pharmacological evaluation

A series of methoxy substituted pyrazole based pyrazoline derivatives (4a-j) were synthesized in good to excellent yield from corresponding pyrazole-chalcones (3a-j). All synthesized derivatives were characterized and screened for their in vitro anti-inflammatory, antioxidant, antidiabetic, and antibacterial activities. Among the series, compounds 4f, 4j, 4a, and 4i showed better anti-inflammatory activity as compared to diclofenac sodium. In DPPH free radical scavenging assay, all the compounds were shown excellent activity and moderate to good activity in SO and NO free radical scavenging assay as compared to standard ascorbic acid. Antibacterial screening of synthesized pyrazolines showed that compounds 4f and 4j have significant antibacterial activity. The compounds 4j, 4f, 4h, 4a, and 4c have shown comparable inhibition of alpha-amylase enzyme leading to good antidiabetic activity as compared to standard acarbose. Molecular docking studies suggest that these compounds have strong binding with COX-2 and alpha-amylase enzyme due to significant capability of aromatic and hydrophobic interaction. The outstanding results of reported compounds in all biological screening will pave the way for the design of new drug candidate bearing pyrazole moiety.

3,4-Dihydropyrimidine-2(1H)-one/thione Derivatives as Anti-inflammatory and Antioxidant Agents: Synthesis, Biological Activity, and Docking Studies

aims: A series of sixteen new 4-(substituted phenyl) - 6-(substituted phenylamino)-3, 4-dihydropyrimidine-2(1H)-ones/thiones derivatives have been synthesized in two step reaction. background: Free radicals are widely known to play a significant part in the inflammatory process. Many non-steroidal anti-inflammatory medicines have been shown to work as radical scavengers or as inhibitors of free radical generation. Inflammation is a part of the vascular tissues' complicated biological reaction to adverse stimuli like bacteria, damaged cells, or irritants. The organism's protective response to damaging stimuli is inflammation, which aims to get rid of them and start the healing process. The inflammatory response has several advantageous effects, such as stopping the spread of dangerous substances to nearby tissues, getting rid of cell waste and infections, and getting the body ready for repair objective: To synthesize new derivatives as anti-inflammatory and antioxidant agents. method: In first step chalcones (I1-I6) was obtained and in the second step, these chalcones were reacted with urea and thiourea in the presence of potassium hydroxide to obtain the corresponding pyrimidinones and thiopyrimidinones. The structures of the synthesized compounds 4-(substituted phenyl)-6-(substituted phenylamino)-3,4-dihydropyrimidine-2(1H)-ones/thione derivatives are investigated by means of TLC (visualized it in Iodine chamber), IR, mass, 1H-NMR spectral and elemental analysis. The title compounds evaluated for anti-inflammatory as well as antioxidant activity. Anti-inflammatory activity in vivo was carried out by carrageenan induced rat-paw edema method and compared with standard drug diclofenac sodium and antioxidant activity was measured by DPPH, FRAP and Hydrogen peroxide (H2O2) method and compared with standard ascorbic acid. result: Electron donating groups showed better antioxidant activity as compared to electron withdrawing ones in both activities. All the compounds exhibited good to moderate activity. Compound DHPM8 shows better antioxidant activity and compound DHPM6 shows better anti-inflammatory activity while compound DHPM11 shows minimum antioxidant as well as anti-inflammatory activity than other compounds. conclusion: To better understanding, we have performed molecular docking simulation. The molecular docking studies revealed that all synthesized compound were showed good receptor binding interaction in which compound 9 had highest docking score of 9.8 due to interaction with CYS36, PRO153, TYR130, GLY45, LEU152, ARG469, LYS468 and GLU465. other: NA

Comparative Studies of Diclofenac Sodium (NSAID) Adsorption on Wheat (Triticum aestivum) Bran and Groundnut (Arachis hypogaea) Shell Powder using Vertical and Sequential Bed Column

Wheat bran and groundnut shell powder have been used to study the mechanism of diclofenac sodium adsorption from aqueous solution using batch as well as column modes and maximum uptake is 84.3% for wheat bran and 82.4% for groundnut shell powder at pH 6, drug concentration 1 mg/L at 298 K for 30min. Isotherm and error analysis reveals that Freundlich and Langmuir isotherms fitted well. Kinetic studies show that the adsorption process follows second-order kinetics and thermodynamic study shows endothermic adsorption process. Column adsorption study is important for industrial scale adsorption and column studies have been carried out using vertical bed and sequential bed adsorption columns at pH 6 which is the optimum pH for maximum adsorption for batch experiments. Vertical and sequential bed columns setup is simple and economical which provides flow under gravity. The effect of varying inlet feed concentration and flow rate on the breakthrough and exhaustion time of columns has been studied to determine the bed capacities of both columns. Thomas model and Yoon-Nelson models fitted well with experimental data for continuous flow column studies.

A novel organic-inorganic hybrid hollow polymer capsule with rich amino/imino groups for anionic contaminant removal in wastewater: Synthesis, performance and mechanism

Herein, we developed a new organic-inorganic hybrid polymer adsorbent, termed PECP, by one-step precipitation polycondensation between polyethyene polyamine and hexachlorocyclotriphosphazene. The morphology and microstructure of PECP were investigated by FTIR, SEM, TEM, XPS, XRD and N2 adsorption. Results show PECP owned a hollow capsule structure and lots of amino/imino groups. The adsorption capacity of PECP for anionic dye methyl orange (MO) was up to 1031.9 mg g-1. The adsorption process was very fast. After five cycles, the adsorption capacity of PECP for MO still remained at 89 % of the initial adsorption capacity. Meanwhile, PECP delivered a high adsorption capacity for other anionic contaminants like acid chrome blue K (1003.5 mg g-1), congo red (1152.2 mg g-1) and diclofenac sodium (914.2 mg g-1). In the binary systems contaminated with double dyes, the separation factors of MO for methylene blue, Rhodamine B and crystal violet were up to 450.8, 55.4 and 355.9, respectively. The experimental data unveiled that the MO removal by PECP was very consistent with the pseudo-second-order kinetic model and the Langmuir isotherm model. The removal process was spontaneous and endothermic. FTIR spectroscopy and XPS analysis confirmed the role of electrostatic force and hydrogen bond on the adsorption of MO on PECP.

Enhanced diclofenac sodium delivery through advanced self-microemulsifying pectin-based transdermal patches

Diclofenac sodium (DCFNa) presents significant challenges in local pain relief due to its poor solubility and limited skin permeability. This study aimed to enhance the solubility and skin permeation of DCFNa by developing DCFNa-loaded self-microemulsifying drug delivery system (SMEDDS) embedded pressure-sensitive adhesive (PSA) patch. The solubility of DCFNa in various solvents was evaluated, and a ternary phase diagram was constructed to optimize the SMEDDS formulation. The transdermal patch, composed of pectin and polyacrylate, was optimized using a simplex lattice experimental design to achieve the desired adhesion strength and to select the most suitable patch for skin drug accumulation study. Clove oil, Tween® 80, and propylene glycol were identified as the appropriate oil, surfactant, and co-surfactant, respectively, for achieving highest DCFNa solubility. The SMEDDS was formed with a ratio of 5:35:60 (oil: Smix [1:1 surfactant: co-surfactant]: water), yielding nano-sized droplets (22.64 ± 0.74 nm) and significantly enhancing DCFNa solubility (329.62 ± 10.16 mg/mL) compared to phosphate buffer (5.03 ± 1.01 mg/mL). The DCFNa-loaded SMEDDS demonstrated a 9-fold increase in skin permeability compared to the DCFNa solution. The optimized PSA patch, containing 20 % pectin and 40 % polyacrylate, exhibited superior tacking and peel strength. Additionally, a 1 % DCFNa-loaded SMEDDS patch delivered twice greater drug accumulation in the skin and showed no skin irritation, maintaining better adhesion for up to 24 h compared to commercial patches.

Room-temperature synthesis of covalent organic frameworks with dual functional groups for high-performance adsorption of diclofenac sodium from aqueous solution

Diclofenac sodium (DCF) are commonly found in ambient waterways due to its widespread use, and this poses significant risks to both human health and ecosystems. In this study, we have designed and synthesized a series of imine-linked covalent organic frameworks (COFs) with dual functional groups using a triple assembly strategy. Specifically, the platform molecules 2,5-dimethoxyterephthalaldehyde (DMTP), 2,5-dihydroxyterephthalaldehyde (DHTP), and 1,3,5-tris(4-aminophenyl)benzene (TAPB) were employed for the direct fabrication of COFs through Schiff base condensation reactions. As a proof of concept, three room-temperature synthesized COFs (COF TAPB-DMTP-[OH]n, where n represents the molar mass of DHTP, with n values of 0.02, 0.03, and 0.04) were used for DCF adsorption from water. The adsorption isotherms, kinetics, pH effects, ionic strength, co-existing ions, and COF regeneration for DCF were thoroughly investigated. The incorporation of methoxy (-OMe) and hydroxyl (-OH) groups serves as a functional strategy to facilitate hydrogen bonding interactions with DCF molecules. Consequently, the developed COFs, featuring an ultrahigh surface area and mesoporous structure, demonstrated a maximum adsorption capacity of 413.2 mg/g and a rate constant k2 of 0.0435 g/mg/min, which exceeds the performance of the majority of previously described adsorbents. The adsorption capacity toward DCF remained nearly unchanged after five regeneration cycles of the COF. Furthermore, the self-prepared adsorbent demonstrated efficient adsorption of DCF from real environmental water, indicating its potential for practical DCF removal applications.

A Review of the Determination of Diclofenac Sodium with Electrochemically Modified Sensors in Various Biological, Pharmaceutical and Water Sources

A Review of the Determination of Diclofenac Sodium with Electrochemically Modified Sensors in Various Biological, Pharmaceutical and Water Sources

Effectiveness of Pulse Intravenous Infusion of Methylprednisolone on Pain in Patients with Lumbar Disc Herniation: A Randomized Controlled Trial

Background: Lumbar disc herniation (LDH) can cause pain in the lower back and leg, as well as numbness or weakness in the affected area. Various steroids, including methylprednisolone, are currently used for treatment. Objectives: This study aimed to compare the effectiveness of pulse intravenous infusion of 500 mg methylprednisolone with common non-steroidal anti-inflammatory drugs (NSAIDs) in relieving pain and improving the clinical condition of patients with lumbar disc herniation. Methods: This clinical trial, registered under code IRCT20211116053077N1, included an experimental group (37 patients) and a control group (35 patients). Pain assessments were conducted before treatment, and at one, two, and three weeks, as well as one and six months after treatment. The control group received common painkillers (diclofenac sodium tablets 100 mg), while the experimental group received a single dose of 500 mg methylprednisolone sodium succinate (intravenous injection in 500 cc normal saline). Pain scores were analyzed using SPSS 16 and statistical tests such as ANOVA, independent t-tests, and repeated measures ANOVA. Results: Prior to intervention, the mean (SD) pain score was 8.7 (3.57) in the experimental group and 8.17 (0.66) in the control group (P > 0.76). Six months after methylprednisolone injection, the mean (SD) pain score in the experimental group was 1.56 (0.83), compared to 6.48 (0.91) in the control group (P = 0.000). Analysis of variance indicated that methylprednisolone significantly reduced pain in patients with LDH (P = 0.000, F = 660.668). Conclusions: Given the effectiveness of intravenous pulse infusion of 500 mg methylprednisolone compared to common NSAIDs in relieving pain and improving clinical outcomes for patients with lumbar disc herniation, the use of this drug is recommended for pain reduction in these patients.

Composite of Organo-LDH and biochar for diclofenac sodium removal from aqueous solutions

Classic layered double hydroxides (LDHs) and their composites with biochar are promising adsorbents for removing emerging contaminants like diclofenac sodium (DFS) from water. However, the use of organo-LDHs in these composites remains unexplored and could enhance their adsorption properties for organic molecules. This study investigates the synthesis, characterization, and application of an organo-LDH based on sodium dodecyl sulfate as intercalating agent (SDS-LDH) and its composite with tangerine peel biochar (SDS-LDH/BC) for the removal of DFS from water. The adsorption performance of these materials was compared with those of a composite of SDS-LDH and tangerine peel biomass (SDS-LDH/Bio) and the layered double oxides (LDOs) obtained from the pyrolysis of SDS-LDH and SDS-LDH/Bio, referred to as SDS-LDO and SDS-LDO/Bio, respectively. The materials were characterized by FTIR, XRD, SEM, TG, and pH point of zero charge analyses, and the adsorption of DFS was evaluated in aqueous medium under different conditions. XRD and FTIR demonstrated the successful incorporation of sodium dodecyl sulfate into the interlamellar space of the SDS-LDH, which was preserved in the SDS-LDH/BC and SDS-LDH/Bio composites. SEM analysis revealed that the SDS-LDH structures, with varied shapes and sizes, were dispersed on the matrix of the biochar, while TG analysis showed that the SDS-LDH/BC had similar thermal stability to SDS-LDH. SDS-LDH achieved 90 % DFS removal at pH 8.0 and 25 °C, while SDS-LDH/BC reached 81 % removal under the same conditions, with maximum DFS adsorption capacities of 247 and 169 mg g−1, respectively, outperforming pristine biochar (no removal). Under the same conditions, SDS-LDH/Bio, SDS-LDO/Bio, and SDS-LDO removed 55 %, 36 %, and 36 % of DFS, respectively. These results revealed the pivotal role of the interlamellar structure of SDS-LDH in DFS adsorption, as confirmed by XRD and FTIR, which indicated that DFS interacted with dodecyl sulfate anion in the SDS-LDH interlamellar space, specially through hydrophobic interaction. Kinetics studies revealed that DFS adsorption on SDS-LDH/BC followed the pseudo-first-order model, while adsorption on SDS-LDH followed the pseudo-second-order model, with equilibrium reached in approximately 30 min. The Redlich-Peterson model satisfactorily fitted the adsorption equilibrium isotherms for both SDS-LDH and SDS-LDH/BC. Although no synergistic effect was observed between biochar and SDS-LDH/BC regarding the adsorption capacity, the formation of the SDS-LDH/BC composite improved the preservation of the SDS-LDH structures, allowing for a lower loss of adsorption capacity upon reuse. These findings suggest that the study of such advanced material can contribute to the development of more effective biochar-LDH composite-based adsorbents, specifically for the removal of organic pollutants.

Interface coupling to improve O2 adsorption and accelerate charge separation for boosting photocatalytic performance of ZnO/ZnIn2S4 composite in H2O2 production and environmental remediation

The key to heterogeneous photo-Fenton technology lies in the efficient generation of hydrogen peroxide (H2O2). Herein, a newly-designed ZnO/ZnIn2S4 composite with heterostructure is synthesized. Benefiting from the formation of built-in electric field, the recombination of photoinduced electrons and holes is suppressed and interfacial charge transfer resistance is reduced. Importantly, the embedding of ZnO in ZnIn2S4 can improve the hydrophobicity and create microscopic three-phase interface, thereby boosting the capture capability for O2 and providing the convenience for the occurrence of O2 reduction reaction. More interestingly, the existence of ZnIn2S4 in the ZnO/ZnIn2S4 composite can reduce the Gibbs free energy (ΔG) of key intermediate (OOH*) formation, which will accelerate the generation of H2O2. As a result, the ZnO/ZnIn2S4 composite displays excellent performance in photocatalytic H2O2 production, and the highest yield was about 897.6 μmol/g/h within 60 min under visible light irradiation. The transfer of photoinduced carriers follows the S-scheme type mechanism. The photogenerated holes can be captured by drug residues (i.e., diclofenac sodium) to accelerate H2O2 production, while generated H2O2 can combine with Fe2+ to construct photo-Fenton system for achieving the advanced degradation of diclofenac sodium, which was mainly related to the formation of OH•. Furthermore, generated H2O2 can be applied for performing the inactivation of pathogenic bacteria. In short, current work will provide a valuable reference for future research.

Response surface methodology-based optimisation of adsorption of diclofenac and treatment of pharmaceutical effluent using combined coagulation-adsorption onto nFe2O3 decorated water chestnut shells biochar.

This work involved the preparation of pristine and iron nanoparticle-loaded biochar from a water chestnut shell to remove diclofenac sodium (DCF) containing effluent of pharmaceutical origin. To create suitable forecasting equations for the modelling of the DCF adsorption onto the adsorbent, response surface methodology (RSM) was used. The parameters, e.g. pH, adsorbent mass, DCF concentration and contact time, were used for the modeling of adsorption. The RSM model predicts that for 98.0% DCF removal, the ideal conditions are pH 6, an adsorbent dose of 0.5 g L-1, and a contact time of 60 min with an initial adsorbate concentration of 25 mg L-1 at 303 K. The maximum capacity deduced from the Langmuir model was 75.9 mg g-1 for pristine water chestnut shell biochar (pWCBC) and 122.3 mg g-1 for magnetically modified nano-Fe2O3 biochar (mWCBC). Under equilibrium conditions, the Langmuir model was the best-suited model compared to the Temkin and Freundlich models. The adsorption data in this investigation efficiently fitted the pseudo-second-order model, emphasizing that chemisorption or ion exchange processes may be involved in the process. The WCBC demonstrated recyclability after 10 cycles of repeated adsorption and desorption of DCF. A combined coagulation adsorption process removed COD, NH3-N, NO3-, PO43-, and DCF by 92.50%, 86.41%, 77.57%, 84.54%, and 97.25%, respectively. This study therefore shows that coagulation followed by adsorption onto biochar can be a cost-effective substitute for conventional pharmaceutical wastewater treatment.

Development of Enteric Diclofenac Sodium Microparticles Through a Spray-Drying Process Facilitated by Different Aqueous Dispersion Systems

The objective of this study was to prepare enteric diclofenac sodium microparticles using an aqueous dispersion system via spray-drying. Two aqueous-based solvent systems, phosphate buffer at pH 7.0 and ammonium hydrogen carbonate solution, were employed as the feed dispersion media in the spray-drying process based on the solubility characteristics of Eudragit® L100. At a drug-to-polymer ratio of 1:1, the optimal solids concentration in the feed dispersion was determined to be 2% w/v, as it enabled an approximately 5-30 µm smooth-surfaced spherical microparticle with a high production yield. Diclofenac sodium was efficiently encapsulated within the microparticles, existing as solid dispersion in a partially amorphous form. Notably, the spray-drying conditions utilized in this study obviated the need for further heating for microparticles prepared using ammonium hydrogen carbonate solution, as the residual ammonium could be completely eliminated during the spray-drying process. The two-stage biorelevant drug release profile of enteric microparticles demonstrated their ability to inhibit drug dissolution under acidic conditions while facilitating drug release under basic conditions. The phosphate buffer-based microparticles exhibited greater protection efficiency under acidic conditions compared to ammonium hydrogen carbonate-based systems, despite residual alkaline salt being present in the microparticles. These results validate the potential of the developed microparticles for use as an enteric drug delivery system.

Applying the SeDeM Expert Diagram System for Characterization of Multiple Component Powder Mixtures for Fixed-dose Combination Matrix-type Tablet Formulations

Background: The SeDeM Expert Diagram System (SeDeM EDS) is an innovative formulation tool that provides an index of compressibility, which can be used to predict a pow-der’s suitability for direct compression to produce acceptable tablets. Objective: This study investigated the application of this tool to evaluate multiple component powder formulation mixtures for direct compression of tablets. The SeDeM EDS was specifically used to characterize powder mixtures for fixed-dose combination (FDC) matrix-type tablets that contained multiple active ingredients, which has not been done previously with SeDeM EDS. Methods: The FDC matrix-type tablets contained diclofenac sodium and vitamins B1, B6 and B12 in fixed ratios, intended for the management of peripheral neuropathy. The parameters of the SeDeM EDS were determined for the multiple-component powder mixtures and the indices were calculated to predict direct compressibility. The FDC tablets were subsequently manufactured uti-lizing direct compression and subjected to pharmacotechnical test evaluations to measure the ac-curacy of the SeDeM EDS’s predictions. Results: This study proved the versatility of the SeDeM EDS and its utility to adequately charac-terize FDC powder mixtures for matrix-type tablets manufactured by direct compression. Addi-tionally, a new calculation was suggested to determine the percentage of corrective excipients re-quired in the case when multiple incidence factor values are below the value of 5. Prediction of the correct quantity of corrective excipient to be added is important to obtain an acceptable direct compressible formulation. Conclusion: The results obtained confirmed that the SeDeM EDS correctly predicted the performance of all formulations.

Probing aqueous diclofenac potassium: Unveiling molecular interactions through dielectric relaxation spectroscopy and MD simulation

Diclofenac potassium (DK) is a salt and undergoes ionization in an aqueous environment. The detailed information about the molecular structure and interactions of such aqueous ionic solutions holds substantial significance in the field of pharmaceutics. This comprehension facilitates the enhancement of pharmaceutical formulations, leading to improved bioavailability, stability, and therapeutic efficacy. It also contributes to the optimization of drug delivery systems. Molecular interactions in the aqueous solutions of DK were studied using dielectric relaxation spectroscopy (DRS) and molecular dynamic (MD) simulation. In DRS, complex dielectric permittivity, ε∗(f) for aqueous solutions of DK of varying concentrations were measured in the frequency range of 20 Hz to 2 MHz at five different temperatures ranging from 303.15 K to 323.15 K. Complex ac conductivity, σ∗(f) and dc conductivity (σdc) were determined from the complex dielectric permittivity. The effect of concentration and temperature on complex permittivity and allied parameters are discussed. The dielectric spectra of aqueous DK reveal dual relaxation processes i.e., normal (n) relaxation and alpha (α) relaxation. The dielectric strength is predominant for α-process and n-process in the low (0 < X ≤ 0.0299) and high (0.029 < X ≤ 0.0822) concentration range respectively. Moreover, Stoke’s relation between dielectric relaxation time, ion mobility and viscosity of the aqueous solutions is discussed. MD simulation at 303.15 K temperature has also been conducted to get additional information on molecular interactions between DK and/or H2O molecules through hydrogen bonding (HB).