Drugs Naproxen Research Articles

Influences of novel microwave drying on dissolution of new formulated naproxen sodium.

Drying of a pharmaceutical composition is an important step during its processing, which can affect its quality attributes including its texture, dispersion of the drug within the formulation, drug dissolution kinetics and eventually the drug's efficacy. This study presents the influence of varying drying techniques on the textural properties of the wet granulated formulation consisting of the drug naproxen sodium (NapSod) during the drying process. A new pharmaceutical formulation consisting of the NapSod drug was prepared by wet granulation and dried by novel microwave drying (MW), freeze drying (FD), vacuum drying (VD), and convective drying (CD) techniques before being processed in the form of tablets. The dissolution rate of NapSod from the tablet was measured in gastric (pH = 1.3) and intestinal fluid (pH = 6.8) mediums. The drug release was found to be influenced by the specific surface area, size distribution and the crystalline structure of dried particles, which were found to vary with the type of drying technique used as confirmed by the results of XRD, FTIR, SEM and particle size analyses. This study shows that using microwave technique to dry pharmaceutical granules containing a polar drug, such as NapSod, is an efficient and economical process, which can maintain the drug release at an appropriate rate to realize its desired pharmaceutical effect.

Manganese(ii) complexes with the non-steroidal anti-inflammatory drugs naproxen and mefenamic acid: synthesis, structure, antioxidant capacity, and interaction with albumins and DNA

The structure, antioxidant activity and interaction with DNA and albumins of a series of manganese(ii) complexes of mefenamic acid or naproxen are presented herein.

Photoactive platinum(II) complexes of nonsteroidal anti-inflammatory drug naproxen: Interaction with biological targets, antioxidant activity and cytotoxicity

The effect on the therapeutic efficacy of Pt(II) complexes on combining non-steroidal anti-inflammatory drugs (NSAIDs) is an attractive strategy to circumvent chronic inflammation mediated by cancer and metastasis. Two square-planar platinum(II) complexes: [Pt(dach)(nap)Cl] (1) and [Pt(dach)(nap)2] (2), where dach = (1R,2R)-dichloro(cyclohexane-1,2-diamine) and NSAID drug naproxen (nap), have been designed for studying their biological activity. The naproxen bound to the Pt(II) centre get released upon photoirradiation with low-power UV-A light as confirmed by the significant enhancement in emission intensities of the complexes. The compounds were evaluated for their photophysical properties, photostability, reactivity with 5′-guanosine monophophosphate (5′-GMP), interactions with CT-DNA and BSA, antioxidant activity and reactive oxygen species mediated photo-induced DNA damage properties. ESI-MS studies demonstrated the formation of bis-adduct with 5′-GMP and the formation of PtII-DNA crosslinks by gel electrophoretic mobility shift assay and ITC studies. The interaction of the complexes 1 and 2 with the CT-DNA exhibits potential binding affinity (Kb ∼ 104 M−1, Kapp∼ 105 M−1), implying intercalation to CT-DNA through planar naphthyl ring of the complexes. Both the complexes also exhibit strong binding affinity towards BSA (KBSA∼ 105 M−1). The complexes exhibit efficient DNA damage activity on irradiation at 365 nm via formation of singlet oxygen (1O2) and hydroxyl radical (•OH) under physiological conditions. Both the complexes were cytotoxic in dark and exhibit significant enhancement of cytotoxicity upon photo-exposure against HeLa and HepG2 cancer cells giving IC50 values ranging from 8 to 12 μM for 1 and 2. The cellular internalization data showed cytosolic and nuclear localization of the complexes in the HeLa cells.

Poly (MAH-β-cyclodextrin-co-NIPAAm) hydrogels with drug hosting and thermo/pH-sensitive for controlled drug release

The lack of identified binding sites for drugs and the undegradability limited the development of the thermo-sensitive hydrogels based on N-isopropylacrylamide (NIPAAm) in the intelligent drug delivery system (DDS). Therefore, the poly (Maleic anhydride-β-cyclodextrin-co-NIPAAm) (poly (MAH-β-CD-co-NIPAAm)) hydrogels were obtained to overcome these disadvantages. β-cyclodextrin (β-CD) with the drug inclusion properties and degradation capacity was modified by maleic anhydride (MAH) and the resultant monomer was fixed in the gel network by a series of polymerization reactions. The physical and chemical properties of the monomer and the poly (MAH-β-CD-co-NIPAAm) hydrogels were systemically investigated. The swelling/deswelling kinetics at different temperature and pH indicated that the gels exhibit dual responsiveness. The model drug naproxen sodium was identified by MAH-β-CD, so it was efficiently loaded on the hydrogels. The drug released in a controlled manner from the copolymerization hydrogels, especially displayed slower release efficiency in simulates stomach conditions. And these hydrogels also showed biodegradability in the presence of α-amylase. The above facts demonstrated that the poly (MAH-β-CD-co-NIPAAm) hydrogels was an effective oral drug system.

Study of pharmaceuticals in surface and wastewater from Cuernavaca, Morelos, Mexico: Occurrence and environmental risk assessment

The present work describes the first known study to date on the occurrence of pharmaceuticals in surface water and wastewater of Cuernavaca, the capital of the state of Morelos (México). Selected pharmaceuticals (a total of 35) were extracted from the collected water samples with a generic solid phase extraction (SPE) protocol and determined in the sample extracts by means of high-performance liquid chromatography coupled to electrospray ionization-tandem mass spectrometry (HPLC-ESI-MS/MS). A screening level risk assessment combining the measured environmental concentrations (MECs) with dose-response data based on predicted no-effect concentrations (PNECs) was also applied to estimate Hazard Quotients (HQs) for the pharmaceuticals detected in the investigated area. A total of twelve pharmaceuticals were found in the water samples analyzed, with detection frequencies above 78% and in most cases of 100%. Overall, the most abundant pharmaceuticals in surface water were the analgesic and anti-inflammatory drugs naproxen (732–4880ng/L), acetaminophen (354–4460ng/L), and diclofenac (258–1398ng/L), and the lipid regulator bezafibrate (286–2100ng/L). On the contrary, other compounds like the β-blocker atenolol and the psychiatric drug carbamazepine were found at only a few ng or tens of ng per liter in the Apatlaco River. Despite the fact that some of the most abundant compounds showed good removal (>97%) during wastewater treatment, concentrations downstream the WWTP were only slightly lower than upstream. This indicates the existence of additional inputs of untreated wastewater into the river. Based on the obtained HQ-values, the concentrations of ibuprofen, sulfamethoxazole, diclofenac and naproxen present in the river could pose a high toxicity risk for the aquatic ecosystem. These findings highlight these pharmaceuticals as relevant organic contaminants in the area of study and the need to further monitor them in order to adopt appropriate measures to safeguard the ecosystem, and eventually human health.

Pharmaceuticals and other anthropogenic chemicals in atmospheric particulates and precipitation

Air and precipitation samples were analyzed by liquid chromatography tandem mass spectrometry (LC-MS/MS) and gas chromatography mass spectrometry (GC–MS) for pharmaceuticals, personal care products, and other commercial chemicals within the St. Paul/Minneapolis metropolitan area of Minnesota, U.S. Of the 126 chemicals analyzed, 17 were detected at least once. Bisphenol A, N,N-diethyl-meta-toluamide (DEET), and cocaine were the most frequently detected; their maximum concentrations in snow were 3.80, 9.49, and 0.171ng/L and in air were 0.137, 0.370, and 0.033ng/m3, respectively. DEET and cocaine were present in samples of rain up to 14.5 and 0.806ng/L, respectively. Four antibiotics - ofloxacin, ciprofloxacin, enrofloxacin, and sulfamethoxazole - were detected at concentrations up to 10.3ng/L in precipitation, while ofloxacin was the sole antibiotic detected in air at 0.013ng/m3. The X-ray contrast agent iopamidol and the non-steroidal anti-inflammatory drug naproxen were detected in snow up to 228ng/L and 3.74ng/L, respectively, while caffeine was detected only in air at 0.069 and 0.111ng/m3. Benzothiazole was present in rain up to 70ng/L, while derivatives of benzotriazole – 4-methylbenzotriazole, 5-methylbenzotriazole, and 5-chlorobenzotriazole - were detected at concentrations up to 1.5ng/L in rain and 3.4ng/L in snow. Nonylphenol and nonylphenol monoethoxylate were detected once in air at 0.165 and 0.032ng/m3, respectively. Although the sources of these chemicals to atmosphere are not known, fugacity analysis suggests that wastewater may be a source of nonylphenol, nonylphenol monoethoxylate, DEET, and caffeine to atmosphere. The land-spreading of biosolids is known to generate PM10 that could also account for the presence of these contaminants in air. Micro-pollutant detections in air and precipitation are similar to the profile of contaminants reported previously for surface water. This proof of concept study suggests that atmospheric transport of these chemicals may partially explain the ubiquity of these contaminants in the aquatic environment.

Synthesis of Multiwalled Carbon Nanotubes–Poly(Methacrylic Acid) Nanohybrid Systems: Characterization, Thermal Properties, and In Vitro Release Studies of Naproxen as a Model Drug

ABSTRACTNanohybrid systems based on carbon nanotubes and pH-sensitive poly(methacrylic acid) were prepared through attaching polymer chains onto carbon nanotubes. First, polymerizable groups were attached onto carbon nanotube walls, then the polymerizable groups were copolymerized with different ratios of methacrylic acid. Obtained systems were studied and characterized through Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy, and transmission electron microscopy. A model drug (naproxen) was entrapped into the prepared materials and in vitro release studies were performed in pH 1 (simulated gastric fluids) and pH 7.4 (simulated intestinal fluids). It was noticed that release in simulated intestinal fluids was faster than simulated gastric fluids, therefore the prepared nanohybrid systems can be considered as appropriate carriers for colon-specific drug delivery.

γ-Polyglutamic acid mediated crosslinking PNIPAAm-based thermo/pH-responsive hydrogels for controlled drug release

The most important drawbacks of the thermo sensitive hydrogels based on N-isopropylacrylamide (NIPAAm) are the lack of other responsive groups and these hydrogels are not biodegradable; moreover, chemical cross-linking agents were commonly used in hydrogels formation process. In order to overcome these inconvenience, poly (NIPAAm-co- poly (γ-glutamic acid) - Allyl glycidyl ether) (poly (NIPAAm-co-γ-PGA-AGE)) hydrogels were obtained by cross-linking polymerization of the corresponding monomers. Poly (γ-glutamic acid) (γ-PGA) of biocompatible and biodegradable was functionalized with an appropriate amount of vinyl groups, thus acting both as a co-monomer and as a bio-degradable cross-linker. The morphology, thermal-behavior, swelling/deswelling kinetics, pH sensitivity and biodegradability of poly (NIPAAm-co-γ-PGA-AGE) hydrogels were studied. The results indicated that the hydrogels not only had good thermal response sensitivities, but also behaved with pH response sensitivities and showed degradation behavior. The hydrogels were loaded with the model drug naproxen and the release studies were performed under simulated physiological conditions. The results showed that drug was efficiently loaded and released in a controlled manner from these hydrogels. In addition, the more amount of γ-PGA-AGE added to the poly (NIPAAm-co-γ-PGA-AGE) hydrogels, the better cytocompatibility of the hydrogels. These hydrogels have more attractive application prospects in the biomedical field.

Design and Synthesis of 1,2,4-Triazolo[3,2-b]-1,3,5-thiadiazine Derivatives as a Novel Template for Analgesic/Anti-Inflammatory Activity.

Previously, we demonstrated that certain heterocyclic compounds derived from 3-substituted-1,2,4-triazole-5-thiones had promising analgesic/anti-inflammatory activities together with low ulcerogenic properties. Therefore, we sought to design and synthesize new derivatives of triazol-5-thiones-fused heterocycles. In the present study, a series of novel bis-Mannich bases, namely 2,6-disubstituted-6,7-dihydro-5H-1,2,4-triazolo[3,2-b]-1,3,5-thiadiazines (1a-d, 2a-c, and 3a-d), were synthesized and characterized to assess their possible anti-inflammatory/analgesic properties. Additionally, their ability to induce gastric toxicity was also evaluated. Several of the condensed compounds produced a degree of analgesic activity comparable to reference drugs in both the hot plate and tail-flick tests. A strong anti-inflammatory effect was observed for the derivatives carrying a benzyl group at the second position (2a-c). The majority of the prepared compounds caused comparatively less gastrointestinal (GI) side effects than the reference drugs naproxen and indomethacin did. These results showed that 1,2,4-triazolo[3,2-b]-1,3,5-thiadiazine derivatives might afford a safer alternative to currently available analgesic/anti-inflammatory agents for the treatment and management of inflammatory disease and pain.

Blocking epithelial-to-mesenchymal transition in glioblastoma with a sextet of repurposed drugs: the EIS regimen.

This paper outlines a treatment protocol to run alongside of standard current treatment of glioblastoma- resection, temozolomide and radiation. The epithelial to mesenchymal transition (EMT) inhibiting sextet, EIS Regimen, uses the ancillary attributes of six older medicines to impede EMT during glioblastoma. EMT is an actively motile, therapy-resisting, low proliferation, transient state that is an integral feature of cancers’ lethality generally and of glioblastoma specifically. It is believed to be during the EMT state that glioblastoma’s centrifugal migration occurs. EMT is also a feature of untreated glioblastoma but is enhanced by chemotherapy, by radiation and by surgical trauma. EIS Regimen uses the antifungal drug itraconazole to block Hedgehog signaling, the antidiabetes drug metformin to block AMP kinase (AMPK), the analgesic drug naproxen to block Rac1, the anti-fibrosis drug pirfenidone to block transforming growth factor-beta (TGF-beta), the psychiatric drug quetiapine to block receptor activator NFkB ligand (RANKL) and the antibiotic rifampin to block Wnt- all by their previously established ancillary attributes. All these systems have been identified as triggers of EMT and worthy targets to inhibit. The EIS Regimen drugs have a good safety profile when used individually. They are not expected to have any new side effects when combined. Further studies of the EIS Regimen are needed.

Inclusion Complexes of a New Family of Non-Ionic Amphiphilic Dendrocalix[4]arene and Poorly Water-Soluble Drugs Naproxen and Ibuprofen.

The inclusion complexes of a new family of nonionic amphiphilic calix[4]arenes with the anti-inflammatory hydrophobic drugs naproxen (NAP) and ibuprofen (IBP) were investigated. The effects of the alkyl chain’s length and the inner core of calix[4]arenes on the interaction of the two drugs with the calix[4]arenes were explored. The inclusion complexes of Amphiphiles 1a–c with NAP and IBP increased the solubility of these drugs in aqueous media. The interaction of 1a–c with the drugs in aqueous media was investigated through fluorescence, molecular modeling, and 1H-NMR analysis. TEM studies further supported the formation of inclusion complexes. The length of lipophilic alkyl chains and the intrinsic cyclic nature of cailx[4]arene derivatives 1a–c were found to have a significant impact on the solubility of NAP and IBP in pure water.

Hand-Ground Nanoscale ZnII -Based Coordination Polymers Derived from NSAIDs: Cell Migration Inhibition of Human Breast Cancer Cells.

Increased levels of intracellular prostaglandin E2 (PGE2 ) have been linked with the unregulated cancer cell migration that often leads to metastasis. Non-steroidal anti-inflammatory drugs (NSAIDs) are known inhibitors of cyclooxygenase (COX) enzymes, which are responsible for the increased PGE2 concentration in inflamed as well as cancer cells. Here, we demonstrate that NSAID-derived ZnII -based coordination polymers are able to inhibit cell migration of human breast cancer cells. Various NSAIDs were anchored to a series of 1D ZnII coordination polymers through carboxylate-Zn coordination, and these structures were fully characterized by single-crystal X-ray diffraction. Hand grinding in a pestle and mortar resulted in the first reported example of nanoscale coordination polymers that were suitable for biological studies. Two such hand-ground nanoscale coordination polymers NCP1 a and NCP2 a, which contained naproxen (a well-studied NSAID), were successfully internalized by the human breast cancer cells MDA-MB-231, as was evident from cellular imaging by using a fluorescence microscope. They were able to kill the cancer cells (MTT assay) more efficiently than the corresponding mother drug naproxen, and most importantly, they significantly inhibited cancer cell migration thereby displaying anticancer activity.

Novel thermoresponsive water-soluble oligomers based on amphiphilic calixresorcinarenes

Novel water-soluble thermoresponsive oligomers TO1 and TO2 were obtained by reaction of amidoamine tetramethylcalixresorcinarenes (C1) and tetrapentylcalixresorcinarenes (C5) with ethylene glycol diglycidyl ether. The compounds were characterised by 1H and FT-PGSE NMR, FTIR, static light scattering and elemental analysis. The thermoresponsive properties of oligomers were investigated by spectrophotometry, DLS, FT-PGSE NMR and TEM. The cloud points of oligomers (43 °C for TO1 (5 mg/ml) and 41 °C for TO2 (1.2 mg/ml), respectively) were determined. The influence of salts effect on TO2 cloud points was investigated. The binding of anti-inflammatory drug naproxen (Nap) at 20 °C by TO1 and TO2 and its partial release at cloud points of oligomers in aqueous solution are observed using fluorescence and FT-PGSE NMR methods. New example of creating of thermoresponsive macrocyclic systems on the basis of amidoamine calixresorcinarenes with possibility of substrate binding and release under the influence of termo-stimuli in an aqueous solution was shown.

Abstract A25: Inhibition or delay of microadenoma development by atorvastatin, naproxen and ED-71 in mice genetically predisposed to colorectal adenomas

Abstract Previous studies by this group demonstrate the ability of chemopreventive agents to differentially inhibit morphological subtypes (flat and polypoid) of colorectal adenomas. Recent efforts have focused on the response of microadenomas, a lesion not routinely evaluated by others, to therapeutic intervention. Microadenomas, or dysplastic aberrant crypt foci (ACFs), are direct precursors of colorectal adenomas and represent the earliest microscopic aberration that can be detected prior to colon tumor formation. The goal of the present study was to: 1) characterize the incidence and multiplicity of microadenomas (≤4 crypts) in Apc+/Min-FCCC mice that spontaneously develop multiple colorectal adenomas, and 2) compare the effect of three classes of chemopreventive agents on microadenoma formation. Animals for baseline histological characterization were subjected to colonoscopic examinations at 7 weeks of age (standard time of treatment initiation) and categorized as tumor-free or tumor-bearing. Forty five percent of the Apc+/Min-FCCC mice without gross colon tumors (N=11) possessed microadenomas at baseline, with an overall average of 0.63 ± 0.29 (Mean ± SEM) per mouse. Among mice with gross tumors at baseline (N=10), 30% had microadenomas (0.3 ± 0.16). Results from treatment studies demonstrate that several agents have the ability to modulate microadenoma formation or progression when administered chronically for 14 weeks. First, atorvastatin (100 ppm), a cholesterol-lowering agent, completely eliminated the formation of microadenomas in mice that were free of gross tumors at baseline (as compared to controls, P = 0.007). In addition, a 33% reduction in tumor incidence was observed among atorvastatin-treated animals at 14 weeks as compared to controls (atorvastatin vs. controls: 55.6% vs. 88.5%, P = 0.017). Second, administration of the non-steroidal anti-inflammatory drug naproxen (400 ppm) caused a significant reduction (89.3%) in the multiplicity of microadenomas as compared to that of animals receiving unsupplemented control diet (0.06 ± 0.06 vs. 0.56 ± 0.24, respectively). Inhibition of microadenomas by naproxen translated into a significant reduction in tumor incidence, (naproxen - 64.7%, controls - 100%, P = 0.0076). Third, ED-71 (eldecalcitol; 1α,25-dihydroxy-2β;-(3-hydroxypropyloxy) Vitamin D3), a novel analog of calcitriol, at a dose of 0.1 μg/kg bw, unexpectedly increased the multiplicity of microadenomas in drug-treated mice as compared to controls (0.9 ± 0.22 vs. 0.5 ± 0.25 P = 0.06, respectively). In contrast, ED-71 reduced the mean incidence of adenomas (> 4 crypts) by 47% (ED-71 - 45.5%, controls 92.3%; P = 0.02) and adenoma multiplicity by 47.6% (ED-71 - 1.1 ± 0.39, controls - 2.1 ± 0.72; P > 0.05) in mice that were free of gross tumors at baseline. These data suggest that ED-71 is effective in preventing the progression of microadenomas to adenomas. In summary, these findings demonstrate the importance of evaluating the response of microadenomas to therapy and suggest that microadenomas represent a promising target for chemopreventive intervention. Supported by CA129467, N01CN43309 and HHSN2610005. * Equal contribution to the abstract. Citation Format: Wen-Chi L. Chang, Harry S. Cooper, Harvey Hensley, Tianyu Li, Karthik Devarajan, Margie L. Clapper. Inhibition or delay of microadenoma development by atorvastatin, naproxen and ED-71 in mice genetically predisposed to colorectal adenomas. [abstract]. In: Proceedings of the AACR Special Conference on Colorectal Cancer: From Initiation to Outcomes; 2016 Sep 17-20; Tampa, FL. Philadelphia (PA): AACR; Cancer Res 2017;77(3 Suppl):Abstract nr A25.

Synthesis and Formulation of Thermosensitive Drug Carrier for Temperature Triggered Delivery of Naproxen Sodium.

Nanospheres and microspheres are known as a multipurpose compounds and are used in various branches of science. Recent controlled delivery systems for drugs are also based on poly-micro and nanospheres. In our study we describe an investigation of the influence of thermosensitive polymer N-isopropylacrylamide (NIPA) on the release of the drug naproxen sodium (NS) with a hydrogel hydroxypropyl methylcellulose (HPMC) base. The hydrodynamic diameter (DH) of the obtained polymer was measured by using dynamic light scattering (DLS) at a wavelength of 678 nm. Hydrogel formulations of NS were prepared in a specific way ex tempore. NS was sprinkled on the surface of a distilled water, then polymer soluted in water was added. Afterward, HPMC was affixed to the solution. Prepared samples were stored at room temperature for 24 h. Release tests showed that modification of thevcross-linker type influenced the properties of synthesized polymeric particles. The NIPA derivatives obtained via surfactant free precipitation polymerization (SFPP) may be formulated as hydrogel preparations using HPMC. The obtained formulations presented varied half-release times, depending on the type of applied NIPA derivatives in hydrogel formulations. At 18 °C, the release rates were lower comparing to the reference HPMC hydrogel, whereas at 42 °C, the release rates were significantly higher. The synthesized thermosensitive polymers enabled temperature-triggered release of NS.

In Situ Impregnation of Silver Nanoclusters in Microporous Chitosan-PEG Membranes as an Antibacterial and Drug Delivery Percutaneous Device.

An in situ synthesis method for preparing silver nanoclusters (AgNCs) embedded in chitosan-polyethylene glycol (CS-PEG) membranes is disclosed. The aim is to develop implantable multifunctional devices for biofilm inhibition and drug release to reduce percutaneous device related complications (PDRCs). A multiple array of characterization techniques confirmed the formation of fluorescent AgNCs with sizes of ∼3 nm uniformly distributed in CS-PEG matrix and their active role in determining the fraction and interconnectivity of the microporous membranes. The presence and increasing contents of AgNCs enhanced the mechanical stability of membranes and decreased their susceptibility to degradation in the presence of lysozyme and H2O2. Moreover, the presence and increasing concentrations of AgNCs hindered biofilm formation against Escherichia coli (Gram negative) and Staphylococcus aureus (Gram positive) and enabled a sustainable release of an anti-inflammatory drug naproxen in vitro until 24 h. The overall results gathered and reported in this work make the AgNCs impregnated CS-PEG membranes highly promising multifunctional devices combining efficient antibacterial activity and biocompatibility with active local drug delivery.

Mechanically tuned nanocomposite coating on titanium metal with integrated properties of biofilm inhibition, cell proliferation, and sustained drug delivery

The clinical success of coated implants in executing biological functions inclusive of sustainable drug release and long term antibacterial activity without antibiotics is critical. To this aim, a nanohybrid of silver nanoparticles (AgNPs) cored in polyvinyl alcohol nanocapsules (Ag-PVA NCs) embedded in chitosan (CS) matrix loaded with anti-inflammatory drug naproxen was prepared. The synthesized nanohybrids that were subjected to coatings on (3-aminopropyl)triethoxysilane (APTES) treated titanium (Ti) metal exhibited dual role of excellent inhibition on biofilm formation and sustained drug release. These dual characteristics are achieved mainly based on intrinsic antibacterial property of AgNPs and differential entrapment of drug in PVA polymeric shell of AgNPs and CS matrix. The coatings also demonstrated enhanced mechanical properties with increasing inorganic filler and stress shielding on Ti metal. The biocompatibility tests involving adhesion, proliferation and differentiation of osteoblast cells demonstrated the efficacy of Ag-PVA NCs embedded in CS matrix as a suitable coating material for orthopedic applications.

Influence of the anode material on the degradation of naproxen by Fenton-based electrochemical processes

This study focuses on the role of the anode material for the electrochemical degradation of the top-selling anti-inflammatory drug naproxen (NPX). Aqueous solutions containing 40mgL−1 NPX sodium in 0.050M NaClO4 at pH 3.0 were comparatively treated by electrochemical advanced oxidation processes (EAOPs) like electro-oxidation with electrogenerated H2O2 (EO-H2O2), electro-Fenton (EF) and UVA photoelectro-Fenton (PEF). The experiments were performed in a 2.5L flow plant equipped with an annular glass photoreactor coupled to a cell with a Pt, IrO2-based (DSA-O2), RuO2-based (DSA-Cl2) or boron-doped diamond (BDD) anode and an air-diffusion cathode to electrogenerate H2O2. In EF and PEF, 0.50mM Fe2+ was added as catalyst. At 50mAcm−2, the oxidation power of EAOPs rose in the order: EO-H2O2<EF<PEF, regardless of the anode used. The IrO2-based anode led to greater mineralization in EO-H2O2 and EF. In contrast, the BDD anode allowed an almost total mineralization in PEF, being superior to 85% attained with the other three materials. DSA, a significantly cheap anode compared to Pt and BDD, can then be a suitable candidate for treating NPX solutions by EAOPs. For each process, the mineralization current efficiency and specific energy consumption were determined. The NPX concentration decay always followed a pseudo-first-order kinetics and, in PEF, it was enhanced in the sequence: RuO2-based<Pt<BDD<IrO2-based. GC–MS analysis of treated solutions allowed detecting six aromatic products, whereas maleic and oxalic acids were identified by ion-exclusion HPLC. A reaction sequence for the degradation of NPX by EAOPs is finally proposed.

Accessing the Physical State and Molecular Mobility of Naproxen Confined to Nanoporous Silica Matrixes

The pharmaceutical drug naproxen was loaded in three different silica hosts with pore diameters of 2.4 (MCM), 3.2 (MCM), and 5.9 nm (SBA), respectively: napMCM_2.4 nm, napMCM_3.2 nm, and napSBA_5.9 nm. To access the guest physical state in the prepared composites, differential scanning calorimetry (DSC), X-ray diffraction (XRD), and attenuated total reflectance Fourier transform infrared spectroscopy were used. The different techniques provided complementary information on a molecular population that was revealed to be distributed among different environments, namely the pore core, the inner pore wall, and the outer surface. It was found that naproxen is semicrystalline in the higher pore size matrix being able to crystallize inside pores; after melting it undergoes full amorphization. In the case of the lower pore size matrix, naproxen crystallizes outside pores due to an excess of filling while most of the remaining fraction is incorporated inside the pores as amorphous. Crystallinity in these two compo...

Calcium(II)–naproxen complex: Synthesis, characterization, and interaction with human serum albumin

ABSTRACTA new calcium(II) complex with anti-inflammatory drug naproxen as ligand was synthesized and characterized. The binding mechanisms of calcium(II)–naproxen complex to human serum albumin (HSA) were investigated under simulative physiological conditions. The acting forces for the binding mechanisms were hydrogen bonds and van der Waals forces. Calcium(II)–naproxen complex and naproxen sodium may competitively bind to HSA at the same active Site I. Albumin binding weakened under the coexistence of the two substances. Thus, combining naproxen sodium and calcium(II)–naproxen complex may enhance treatment efficacy because of the synergistic effect.