Olive industry liquid waste from trash to metal adsorbent for wastewater purification.

The development of biobased polymeric materials for wastewater purification has become a demand due to the growing need for water free of hazardous metal ions for safe purposes. The organic components of the OLLW including carbohydrates, phenolics, aromatic acids and others are cost-effective and sustainable choices for this application. This work focuses on a method for turning the organic components of liquid waste from the olive industry (OILW) into a foam-based value-added polymer that has several metal ion binding sites. The process of making the target polymers involved reacting the components of the OILW with hexamethylene diisocyante and 1,4-phnyelene diisocynate to create the polymeric materials LHMIDIC and LPDIC that are in foam forms with urethane linkages, respectively. The adsorption competence of the polymeric foams toward Pb(II) was evaluated as a function of various parameters including adsorbent dose, pH, temperature, initial ion concentration and time. The optimum parameters values that led to a quantitative removal of Pb(II) were identified. The obtained thermodynamic parameters showed that the adsorption by the two foams was spontaneous at room temperature. The isothermal and kinetic values showed that the adsorption by synthesized foams follows a second order kinetic and obeys the Langmuir isothermal model. The foams showed a high tendency for removing multi metal ions present in a real sample of wastewater. The original nature of the starting material used in making the foam, cost and the obtained results showed the potential of using the foam in a large-scale plants of wastewater purification.

Inhibition of the renal apical sodium dependent bile acid transporter prevents cholemic nephropathy in mice with obstructive cholestasis.

BACKGROUND & AIMS: Cholemic nephropathy (CN) is a severe complication of cholestatic liver diseases for which there is no specific treatment. We revisited its pathophysiology with the aim of identifying novel therapeutic strategies. METHODS: Cholestasis was induced by bile duct ligation (BDL) in mice. Bile flux in kidneys and livers was visualized by intravital imaging, supported by MALDI mass spectrometry imaging and liquid chromatography-tandem mass spectrometry. The effect of AS0369, a systemically bioavailable apical sodium-dependent bile acid transporter (ASBT) inhibitor, was evaluated by intravital imaging, RNA-sequencing, histological, blood, and urine analyses. Translational relevance was assessed in kidney biopsies from patients with CN, mice with a humanized bile acid (BA) spectrum, and via analysis of serum BAs and KIM-1 (kidney injury molecule 1) in patients with liver disease and hyperbilirubinemia. RESULTS: Proximal tubular epithelial cells (TECs) reabsorbed and enriched BAs, leading to oxidative stress and death of proximal TECs, casts in distal tubules and collecting ducts, peritubular capillary leakiness, and glomerular cysts. Renal ASBT inhibition by AS0369 blocked BA uptake into TECs and prevented kidney injury up to 6 weeks after BDL. Similar results were obtained in mice with humanized BA composition. In patients with advanced liver disease, serum BAs were the main determinant of KIM-1 levels. ASBT expression in TECs was preserved in biopsies from patients with CN, further highlighting the translational potential of targeting ASBT to treat CN. CONCLUSIONS: BA enrichment in proximal TECs followed by oxidative stress and cell death is a key early event in CN. Inhibiting renal ASBT and consequently BA enrichment in TECs prevents CN and systemically decreases BA concentrations. IMPACT AND IMPLICATIONS: Cholemic nephropathy (CN) is a severe complication of cholestasis and an unmet clinical need. We demonstrate that CN is triggered by the renal accumulation of bile acids (BAs) that are considerably increased in the systemic blood. Specifically, the proximal tubular epithelial cells of the kidney take up BAs via the apical sodium-dependent bile acid transporter (ASBT). We developed a therapeutic compound that blocks ASBT in the kidneys, prevents BA overload in tubular epithelial cells, and almost completely abolished all disease hallmarks in a CN mouse model. Renal ASBT inhibition represents a potential therapeutic strategy for patients with CN.

Green synthesis of fluorescent carbon nanodots from sage leaves for selective anticancer activity on 2D liver cancer cells and 3D multicellular tumor spheroids.

Carbon nanodots, a family of carbon-based nanomaterials, have been synthesized through different methods from various resources, affecting the properties of the resulting product and their application. Herein, carbon nanodots (CNDs) were synthesized with a green and simple hydrothermal method from sage leaves at 200 °C for 6 hours. The obtained CNDs are well dispersed in water with a negative surface charge (ζ-potential = -11 mV) and an average particle size of 3.6 nm. The synthesized CNDs showed concentration-dependent anticancer activity toward liver cancer (Hep3B) cell lines and decreased the viability of the cancer cells to 23% at the highest used concentration (250 µg ml-1 of CNDs). More interestingly, the cytotoxicity of the CNDs was tested in normal liver cell lines (LX2) revealed that the CNDs at all tested concentrations didn't affect their viability including at the highest concentration showing a viability of 86.7%. The cellular uptake mechanisms of CNDs were investigated and they are thought to be through energy-dependent endocytosis and also through passive diffusion. The main mechanisms of endocytosis were lipid and caveolae-mediated endocytosis. In addition, the CNDs have hindered the formation of 3D spheroids from the Hep3B hepatocellular carcinoma cell line. Hence, it would be concluded that the synthesized CNDs from sage are more highly selective to liver cancer cells than normal ones. The CNDs' cancer-killing ability would be referred to as the production of reactive oxygen species.

Covalent functionalization of graphene sheets for plasmid DNA delivery: experimental and theoretical study.

Several approaches, including plasmid transfection and viral vectors, were used to deliver genes into cells for therapeutic and experimental purposes. However, due to the limited efficacy and questionable safety issues, researchers are looking for better new approaches. Over the past decade, graphene has attracted tremendous attention in versatile medical applications, including gene delivery, which could be safer than the traditional viral vectors. This work aims to covalently functionalize pristine graphene sheets with a polyamine to allow the loading of plasmid DNA (pDNA) and enhance its delivery into cells. Graphene sheets were successfully covalently functionalized with a derivative of tetraethylene glycol connected to polyamine groups to improve their water dispersibility and capacity to interact with the pDNA. The improved dispersibility of the graphene sheets was demonstrated visually and by transmission electron microscopy. Also, it was shown by thermogravimetric analysis that the degree of functionalization was about 58%. Moreover, the surface charge of the functionalized graphene was +29 mV as confirmed by zeta potential analysis. The complexion of f-graphene with pDNA was achieved at a relatively low mass ratio (10 : 1). The incubation of HeLa cells with f-graphene loaded with pDNA that encodes enhanced green fluorescence protein (eGFP) resulted in the detection of fluorescence signal in the cells within one hour. f-Graphene showed no toxic effect in vitro. Density functional theory (DFT) and quantum theory of atoms in molecules (QTAIM) calculations revealed strong binding with ΔH 298 = 74.9 kJ mol-1. QTAIM between the f-graphene and a simplified model of pDNA. Taken together, the developed functionalized graphene could be used for the development of a new non-viral gene delivery system.

Olive Industry Solid Waste-Based Biosorbent: Synthesis and Application in Wastewater Purification.

In this work, we present a process for converting olive industry solid waste (OISW) into a value-added material with ionic receptors for use in the removal of toxic metal ions from wastewater. This 3D polymer is a promising adsorbent for large-scale application, since it is a low-cost material made from agricultural waste and showed exceptional performance. The synthesis of the network polymer involved the carboxymethylation of OISW and curing of the carboxymethylated OISW at an elevated temperature to promote the formation of ester linkages between OISW's components. FT-IR, atomic force microscopy, and thermal analysis were performed on the crosslinked product. The adsorption efficiency of the crosslinked carboxymethylated OISW toward Pb(II), Cu(II), and other toxic metal ions present in sewage was evaluated as a function of adsorbent dose, temperature, pH, time, and initial metal ion. The percentage removal of about 20 metal ions present in a sewage sample collected from a sewer plant located in the Palestinian Territories was determined. The adsorption efficiency did not drop even after six cycles of use. The kinetic study showed that the adsorption process follows the Langmuir isotherm model and the second-order adsorption rate. The experimental Qe values of 13.91 and 13.71 mg/g were obtained for Pb(II) and Cu(II) removal, respectively. The thermodynamic results confirm the spontaneous metal bonding to the receptor sites of the crosslinked carboxymethylated OISW.

Correction: Optical properties and photoactivity of carbon nanodots synthesized from olive solid wastes at different carbonization temperatures.

[This corrects the article DOI: 10.1039/D1RA09273A.].

The Formation of Self-Assembled Nanoparticles Loaded with Doxorubicin and d-Limonene for Cancer Therapy.

Self-assembled nanoparticles present unique properties that have potential applications in the development of a successful drug delivery system. Doxorubicin (DOX) is an important anti-neoplastic anthracycline chemotherapeutic drug widely described. However, it suffers from serious dose-dependent cardiotoxicity. d-Limonene is a major constituent of numerous citrus oils that is considered a specific monoterpene against free radicals producing antioxidant activity. Herein, we aimed to design three types of self-assembled nanodelivery systems (nanoemulsion, niosomes, and polylactide nanoparticles) for loading both DOX and d-limonene to enhance the solubilization of d-limonene and provide antioxidant activity with excellent anticancer activity. As confirmed by dynamic light scattering and transmission electron microscopy, the nanoparticles were prepared successfully with diameter sizes of 52, 180, and 257 nm for the DOX-loaded nanoemulsion, niosomes, and polylactide nanoparticles, respectively. The zeta potential values were above -30 mV in all cases, which confirms the formation of stable nanoparticles. The loading efficiency of DOX was the highest in the case of the DOX-loaded nanoemulsion (75.8%), followed by niosomes (62.8%), and the least was in the case of polylactide nanoparticles with a percentage of 50.2%. The in vitro release study of the DOX-loaded nanoparticles showed a sustained release profile of doxorubicin with the highest release in the case of DOX-loaded PDLLA nanoparticles. The kinetic release model for all developed nanoparticles was the Peppas-Sahlin model, demonstrating DOX release through Fickian diffusion phenomena. Moreover, all developed nanoparticles maintain the antioxidant activity of d-limonene. The cytotoxicity study of the DOX-loaded nanoparticles showed concentration-dependent anticancer activity with excellent anticancer activity in the case of the DOX-loaded nanoemulsion and polylactide nanoparticles. These nanoparticles will be further studied in vivo to prove the cardioprotective effect of d-limonene in combination with DOX.

Broad-Spectrum Antibacterial Activity of Synthesized Carbon Nanodots from d-Glucose.

Carbon nanodots, a class of carbon nano-allotropes, have been synthesized through different routes and methods from a wide range of precursors. The selected precursor, synthetic method, and conditions can strongly alter the physicochemical properties of the resulting material and their intended applications. Herein, carbon nanodots (CNDs) have been synthesized from d-glucose by combining pyrolysis and chemical oxidation methods. The effect of the pyrolysis temperature, equivalents of oxidizing agent, and refluxing time were studied on the product and quantum yield. In the optimum conditions (pyrolysis temperature of 300 °C, 4.41 equiv of H2O2, 90 min of reflux) CNDs were obtained with 40% and 3.6% of product and quantum yields, respectively. The obtained CNDs are negatively charged (ζ-potential = -32 mV), excellently dispersed in water, with average diameter of 2.2 nm. Furthermore, ammonium hydroxide (NH4OH) was introduced as dehydrating and/or passivation agent during CNDs synthesis resulting in significant improvement of both product and quantum yields of about 1.5 and 3.76-fold, respectively. The synthesized CNDs showed a broad spectrum of antibacterial activities toward different Gram-positive and Gram-negative bacteria strains. Both synthesized CNDs caused highly colony forming unit reduction (CFU), ranging from 98% to 99.99% for most of the tested bacterial strains. However, CNDs synthesized in the absence of NH4OH, due to a negatively charged surface enriched in oxygenated groups, performed better in zone inhibition and minimum inhibitory concentration. The elevated antibacterial activity of high-oxygen-containing carbon nanodots is directly correlated to their ROS formation ability.

Noncovalent functionalization of carbon nanotubes as a scaffold for tissue engineering.

Tissue engineering is one of the hot topics in recent research that needs special requirements. It depends on the development of scaffolds that allow tissue formation with certain characteristics, carbon nanotubes (CNTs)-collagen composite attracted the attention of the researchers with this respect. However, CNTs suffer from low water dispersibility, which hampered their utilization. Therefore, we aim to functionalize CNTs non-covalently with pyrene moiety using an appropriate hydrophilic linker derivatized from polyethylene glycol (PEG) terminated with hydroxyl or carboxyl group to disperse them in water. The functionalization of the CNTs is successfully confirmed by TEM, absorption spectroscopy, TGA, and zeta potential analysis. 3T3 cells-based engineered connective tissues (ECTs) are generated with different concentrations of the functionalized CNTs (f-CNTs). These tissues show a significant enhancement in electrical conductivity at a concentration of 0.025%, however, the cell viability is reduced by about 10 to 20%. All ECTs containing f-CNTs show a significant reduction in tissue fibrosis and matrix porosity relative to the control tissues. Taken together, the developed constructs show great potential for further in vivo studies as engineered tissue.

Optical properties and photoactivity of carbon nanodots synthesized from olive solid wastes at different carbonization temperatures.

Carbon nanodots (CNDs) have many fascinating properties, such as optical properties (UV-Visible absorption and fluorescence emission), which make them good candidates in many applications, such as photocatalysts for the degradation of several organic pollutants. This study aims to synthesize CNDs from olive solid wastes at different carbonization temperatures from 300 to 900 °C and study the effect on the optical properties of the CNDs, such UV-Vis, fluorescence, quantum yield, and energy bandgap, in addition to the influence on the photoactivity of the CNDs as photocatalysts for the degradation of methylene blue (MB). CNDs were prepared from olive solid wastes (OSWs) by pyrolysis at different temperatures (300-900 °C) for conversion to carbonized material, and then oxidized chemically in the presence of hydrogen peroxide (H2O2). It was found that an increase in the carbonization temperature of the OSWs leads to an increase in the product yield with a maximum value at 500 °C, and it then decreased dramatically. On the other hand, a decrease in fluorescence due to the diminishment of oxygen groups and the destruction of the surface of the CNDs was observed. The higher quantum yield (5.17%) and bandgap (2.77 eV) were achieved for CNDs prepared from OSWs that carbonized at 300 °C. The rate and degradation efficiency of MB were studied with the different synthesized CNDs, and it was found that an increase in the carbonization temperature leads to a decrease in the rate and degradation efficiency of MB, with the highest degradation rate of 0.0575 min-1 and degradation efficiency of 100% after 120 minutes of light irradiation being realized for the sample carbonized at 300 °C.

Features, applications, and sustainability of lipid nanoparticles in cosmeceuticals.

Cosmeceuticals are a branch of cosmetic products that forms a bridge between cosmetic and drug products. It is a fast-growing branch of the cosmetic industry, especially after the introduction of novel formulation and manufacturing techniques such as lipid nanoparticles (LNPs). These LNPs-based cosmeceutical products offer several advantages such as enhanced bioavailability of cosmeceutical active ingredients (CAIs), improved aesthetic appeal, and stability of the final products. However, the use of these LNPs may raise some concerns about possible side effects of these LNPs and potential hazards to the customer's health. Accordingly, an update that focuses on the use of this important branch of nanoparticles is necessary since most review papers are dealing with all types of nanocarriers in the same review with little focus on LNPs. Therefore, in the current review, a detailed analysis of the advantages and disadvantages of LNPs in this field was highlighted, to emphasize the LNPs-based cosmeceuticals on the market, as well as the potential risk posed by LNPs on exposure and recently introduced regulatory guidelines to address them. In addition, if these products can be a candidate as products that meet the sustainable development goals raised by the UN are discussed.

Synthesis of Rutin Derivatives to Enhance Lipid Solubility and Development of Topical Formulation with a Validated Analytical Method.

BACKGROUND: Rutin is available on the market as a topical formulation for the treatment of several conditions, such as internal bleeding, hemorrhoids, and varicose veins. However, these gels have low solubility and limited bioavailability due to their decreased lipid solubility. OBJECTIVE: In this study, we aimed to synthesize potentially novel lipophilic rutin prodrugs. The suggested library of these rutin prodrugs includes changing the solubility profile to facilitate rutin transport across biological barriers, thereby improving drug delivery through topical application. METHODS: Six rutin derivatives were synthesized based on the ester prodrug strategy. The synthesized compounds were formulated as topical ointments, and their permeability via Franz diffusion was measured. An ultraviolet (UV) analytical method was developed in our laboratories to quantify rutin derivatives both as raw materials and in final dosage forms. The analytical method was then validated. RESULTS: The results of Franz diffusion analyses showed that transdermal permeability increased by 10-fold for decaacetylated rutin compared to the other esterified rutins. A simple analytical method for the analysis of the formulated rutin ester was developed and validated. Moreover, the formulated ointment of decaacetylated rutin in our research laboratory was found to be stable under stability accelerated conditions. Synthesis of potentially more lipophilic compounds would yield novel rutin prodrugs suitable for topical formulation. CONCLUSION: This project provides a synthetic approach for many similar natural products. The research idea and strategy followed in this research project could be adapted by pharmaceutical and herbal establishments.

Modulating the Biomechanical Properties of Engineered Connective Tissues by Chitosan-Coated Multiwall Carbon Nanotubes.

BACKGROUND: Under certain conditions, the physiological repair of connective tissues might fail to restore the original structure and function. Optimized engineered connective tissues (ECTs) with biophysical properties adapted to the target tissue could be used as a substitution therapy. This study aimed to investigate the effect of ECT enforcement by a complex of multiwall carbon nanotubes with chitosan (C-MWCNT) to meet in vivo demands. MATERIALS AND METHODS: ECTs were constructed from human foreskin fibroblasts (HFF-1) in collagen type I and enriched with the three different percentages 0.025, 0.05 and 0.1% of C-MWCNT. Characterization of the physical properties was performed by biomechanical studies using unidirectional strain. RESULTS: Supplementation with 0.025% C-MWCNT moderately increased the tissue stiffness, reflected by Young's modulus, compared to tissues without C-MWCNT. Supplementation of ECTs with 0.1% C-MWCNT reduced tissue contraction and increased the elasticity and the extensibility, reflected by the yield point and ultimate strain, respectively. Consequently, the ECTs with 0.1% C-MWCNT showed a higher resilience and toughness as control tissues. Fluorescence tissue imaging demonstrated the longitudinal alignment of all cells independent of the condition. CONCLUSION: Supplementation with C-MWCNT can enhance the biophysical properties of ECTs, which could be advantageous for applications in connective tissue repair.

Dual covalent functionalization of single-walled carbon nanotubes for effective targeted cancer therapy.

Chemotherapy is a mainstay strategy in the management of cancer. Regrettably, current chemotherapeutic agents are cytotoxic not only to cancer cells but also to healthy cells, resulting in dose-limiting serious side effects. Therefore, many researchers are eager to develop new drug delivery systems that may help to decrease the side effects and the target delivery of chemotherapy to cancer cells. One of the epochal drug delivery systems in this field is based on carbon nanotubes technology. The aim of this work is the dual covalent functionalization of single-walled carbon nanotubes (SWCNTs) with doxorubicin (DOX) connected with acid-labile linkage and mannose (Man) as a targeting agent. The characterization of the developed nano-drug by transmission electron microscopy showed good dispersibility of the functionalized SWCNTs with diameters (6-10) nm. Moreover, the percentage of functionalization was determined by thermogravimetric analysis showing 25% of functionalization in the case of SWNCTs-NHN-DOX (7) and 51% for SWCNTs-Man-NHN-DOX (11). The in vitro release profile of Dox from SWNCTs-NHN-DOX (7) showed 45% of the loaded drug was released over 18 h at pH 7.4 and almost complete release at pH 6.4 at 37 °C. However, the in vitro release profile of Dox from SWCNTs-Man-NHN-DOX (11) showed 75% of the loaded drug was released over 5 h at pH 6.4 at 37 °C. The cytotoxic effect of the compounds was studied on liver cancer cells (HepG2) at different concentrations and different pH conditions and was compared with DOX alone. The cytotoxicity of compounds SWCNTs-NHN-DOX (7) and SWCNTs-Man-NHN-DOX (11) was enhanced at pH 6.5, where the cell viability in both test compounds was significantly reduced by almost 50% compared to the cell viability at pH 7.4 for the same test compound Moreover, the pre-incubation of cells with different concentrations of mannose reduced the cytotoxicity of compound (11) by more than 50%, suggesting that the entry of this complex could be at least in part facilitated by mannose receptors, which imparts this complex a kind of selectivity for cancer cells that overexpress this type of receptors.

Self-assembly of diclofenac prodrug into nanomicelles for enhancing the anti-inflammatory activity.

Non-steroidal anti-inflammatory drugs (NSAIDs) are widely prescribed for the treatment of various types of inflammatory conditions. Diclofenac is a very common NSAID that is utilized to relieve pain and reduce fever and, most importantly, inflammation. However, it suffers from low water solubility and a low dissolution profile. Therefore, we aim to develop a new drug delivery system based on the synthesis of amphiphilic structures that are capable of self assembling into nano-micelles which will be a water-soluble delivery system for the diclofenac. The amphiphilic structure consists of a hydrophilic moiety of triethylene glycol (TEG), polyethylene glycol PEG 400, or PEG 600 linked with the hydrophobic drug diclofenac through an ester linkage. The diclofenac derivatives were successfully synthesized as confirmed by nuclear magnetic resonance. Moreover, the formation of the micellar structure of the synthesized amphiphilic derivatives was confirmed by atomic force microscopy obtaining a spherical shape of the micelles with average diameters of 200 nm for Dic-PEG400-Dic, and 110 nm for Dic-PEG600-Dic. The critical micelle concentration has been determined as 2.7 × 10-3 mg mL-1 for Dic-PEG400-Dic, and 1 × 10-4 mg mL-1 for Dic-PEG600-Dic. The in vitro diclofenac release profile by esterase enzyme was conducted and showed almost complete conversion to free diclofenac within 35 h in the case of Dic-PEG400-Dic micelles and more than 85% of Dic-PEG600-Dic micelles. Then the anti-inflammatory activity was determined by testing the TNF-α production in LPS-stimulated Balb/c mice. Diclofenac micelles significantly suppressed TNF-α production after a 5 mg kg-1 dose was given. The developed micelles showed TNF-α inhibition up to 87.4% and 84% after 48 hours of treatment in the case of Dic-PEG400-Dic and Dic-PEG600-Dic micelles respectively in comparison to 42.3% in the case of diclofenac alone. Dic-PEG400-Dic micelles showed the most potent anti-inflammatory activity with improved TNF-α suppression through time progress. Therefore, the developed nano-micelles provide a facile synthetic approach to enhance diclofenac water solubility, improve the anti-inflammatory effect and achieve a sustained release profile to get better patient compliance.

Design of multicomponent indomethacin-paracetamol and famotidine loaded nanoparticles for sustained and effective anti-inflammatory therapy.

Indomethacin is one of the nonsteroidal anti-inflammatory drugs (NSAIDs) that are widely prescribed drug for pain and inflammation. However, its notoriety of causing gastrointestinal effect, low water solubility, and its short half-life would affect patient compliance and its oral absorption and accordingly justify the need to develop a formula with a controlled and sustained release manner in combination with anti-ulcer drugs. Herein, we synthesized indomethacin-paracetamol co-drug loaded in nanoemulsion and encapsulated in famotiditine loaded polycaprolactone (PCL) nanoparticles. The synthesis of the co-drug was achieved by the formation of a hydrolyzable ester between the indomethacin and paracetamol. The synthesized co-drug was preloading in nanoemulsion (Co-NE), which encapsulated into famotidine PCL nanoparticles utilizing the nanoprecipitation approach. The developed nanosystem showed hydrodynamic size less than 200 nm and the zeta potential value above -30 mV. TEM images confirmed the morphological structure of the formed nanoemulsion and the loaded PCL nanoparticles. Stability studies revealed that the developed nanosystem was stable at different temperatures and pHs over 1 month. Moreover, improvement of the solubilities of these three drugs leading to have a controlled-release multicomponent system of both co-drug and famotidine over 3 days. This multicomponent nanoparticle might be a potential platform to overcome the obstacles of NSAIDs, synergize drugs with different mechanisms of actions by co-encapsulating a small-sized nanoemulsion into PCL nanoparticles for reaching the goal of effective anti-inflammatory therapy.

RP-HPLC Method Development and Validation of Synthesized Codrug in Combination with Indomethacin, Paracetamol, and Famotidine.

BACKGROUND: Indomethacin is considered a potent nonsteroidal anti-inflammatory drug that could be combined with Paracetamol to have superior and synergist activity to manage pain and inflammation. To reduce the gastric side effect, they could be combined with Famotidine. Methodology. A codrug of Indomethacin and Paracetamol was synthesized and combined in solution with Famotidine. The quantification of the pharmaceutically active ingredients is pivotal in the development of pharmaceutical formulations. Therefore, a novel reverse-phase high-performance liquid chromatography (RP-HPLC) method was developed and validated according to the International Council for Harmonization (ICH) Q2R1 guidelines. A reverse phase C18 column with a mobile phase acetonitrile: sodium acetate buffer 60 : 40 at a flow rate of 1.4 mL/min and pH 5 was utilized. RESULTS: The developed method showed good separation of the four tested drugs with a linear range of 0.01-0.1 mg/mL (R 2 > 0.99). The LODs for FAM, PAR, IND, and codrug were 3.076 × 10-9, 3.868 × 10-10, 1.066 × 10-9, and 4.402 × 10-9 mg/mL respectively. While the LOQs were 9.322 × 10-9, 1.172 × 10-10, 3.232 × 10-9, and 1.334 × 10-8 mg/mL, respectively. Furthermore, the method was precise, accurate, selective, and robust with values of relative standard deviation (RSD) less than 2%. Moreover, the developed method was applied to study the in vitro hydrolysis and conversion of codrug into Indomethacin and Paracetamol. CONCLUSION: The codrug of Indomethacin and Paracetamol was successfully synthesized for the first time. Moreover, the developed analytical method, to our knowledge, is the first of its kind to simultaneously quantify four solutions containing the following active ingredients of codrug, Indomethacin, Paracetamol, and Famotidine mixture with added pharmaceutical inactive ingredients in one HPLC run.

Covalent Functionalization of Graphene Sheets with Different Moieties and Their Effects on Biological Activities.

The ongoing spread of multi-drug-resistant bacteria over the past few decades necessitates collateral efforts to develop new classes of antibacterial agents with different mechanisms of action. The utilization of graphene nanosheets has recently gained attention with this respect. Herein, we have synthesized and tested the antibacterial activity of an array of graphene materials covalently functionalized with hydroxyl-, amine-, or carboxyl-containing groups. Fourier transform infrared spectroscopy and transmission electron microscopy confirmed successful functionalization of the few-layer graphene (FLG). The percentage of weight loss was measured by thermogravimetric analysis, which was found to be 22%, 23%, and 37% for FLG-TEG-OH, FLG-NH2, and FLG-DEG-COOH, respectively. In comparison with pristine graphene sheets, the functionalized few-layer graphene (f-FLG) materials gained an adequate dispersibility in water as confirmed by ζ potential analysis. Moreover, there was a significant improvement in the antibacterial activity against Staphylococcus aureus and Escherichia coli, where all f-FLG compounds were able to suppress bacterial growth, with a complete suppression achieved by FLG-DEG-COOH. The minimum inhibitory concentration (MIC) was 250 µg mL-1 for both FLG-TEG-OH and FLG-NH2, while it was 125 µg mL-1 for FLG-DEG-COOH. The glutathione oxidation test demonstrated an oxidative stress activity by all f-FLG compounds. However, FLG-DEG-COOH demonstrated the highest reduction in glutathione activity. FLG-DEG-COOH and FLG-TEG-OH showed adequate biocompatibility and hemocompatibility. The chemical functionalization of graphene might be a step toward the foundation of an effective class of antimicrobial agents.

Surface modulation of single-walled carbon nanotubes for selective bacterial cell agglutination.

BACKGROUND: Bacterial resistance to antibiotics is one of the biggest challenges facing medicine today. Anti-adhesive therapy, using inhibitors of bacterial adhesion to epithelial cells, one of the first stages of infection, is a promising approximation in this area. The size, shape, number of sugar and their placement are variables that have to be taken into account in order to develop multivalent systems able to inhibit the bacterial adhesion based on sugar-lectin interaction. MATERIALS AND METHODS: In the present work we report a modular approach for the synthesis of water-soluble 1D-carbon nanotube-sugar nanoconstructs, with the necessary flexibility to allow an efficient sugar-lectin interaction. The method is based on the reaction of aryl diazonium salts generated in situ from aniline-substituted mannose and lactose derivatives with single wall carbon nanotubes (SWCNTs) sidewalls. RESULTS: Two hybrid nanosystems, I-II, exposing mannose or lactose and having a tetraethylene glycol spacer between the sugar and the nanotube sidewall were rapidly assembled and adequately characterized. The sweet nano-objects were then tested for their ability to agglutinate and selectively inhibit the growth of uropathogenic Escherichia coli. These studies have shown that nanosystem I, exposing mannose on the nanotube surface is able to agglutinate and to inhibit the bacterial growth unlike nano-objects II exposing lactose. CONCLUSION: The results reported constitute a proof of principle in using mannose-coated 1D-carbon nanotubes as antiadhesive drugs that compete for FimH binding and prevent the uropathogenic bacteria from adhering to the urothelial surface.

Combretastatin A4-camptothecin micelles as combination therapy for effective anticancer activity.

Cancer is a major worldwide health problem, for which chemotherapy is a common treatment option. However drug toxicity and the development of resistance to chemotherapy are two main challenges associated with the traditional anticancer drugs. Combined pharmacological therapy based on different mechanisms might be an effective strategy in cancer treatment, and could exhibit a synergistic therapeutic efficacy. Herein, we aim to combine combretastatin A4 (CA4) and camptothecin (Cpt) chemically into a codrug through two hydrophilic linkers utilizing click chemistry to improve their water solubility and anticancer activity. The synthesized amphiphilic structure could self-assemble into a micelle structure as confirmed by atomic force microscopy (AFM) and dynamic light scattering (DLS), which showed a high stability and improved water solubility at pH 7.4, with a low critical micelle concentration (CMC) value of 0.9 mM. Moreover, in vitro hydrolysis was observed upon incubation of the hybrid compound with an esterase enzyme, which suggested a complete disassembly into the starting active drugs. Finally, cytotoxicity studies on HeLa cancer cells showed that the codrug demonstrated an enhanced (five fold) cytotoxicity as compared with the free drugs. In addition the combination index (CI) was <1, which suggests a synergistic activity for the codrug. Moreover, the tested concentrations of the codrug were not significantly cytotoxic to a noncancerous fibroblast cell line. The imaging of HeLa cells treated with FITC-loaded micelles showed a rapid internalization. In conclusion, the codrug of CA4 and Cpt might be a potential novel anticancer drug as it demonstrated a synergistic cytotoxic activity that might spare noncancerous cells.