• Title/Summary/Keyword: cationic agent

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Effect of Polysorbate 80 and Benzyl Alcohol on the Solubility of Amiodarone Hydrochloride

  • LEONTIEV, Viktor;LAZOVSKAYA, Olesya
    • The Korean Journal of Food & Health Convergence
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    • v.5 no.4
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    • pp.13-17
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    • 2019
  • Amiodarone hydrochloride is an antiarrhythmic agent which has low aqueous solubility and presents bioavailability problem. These properties are a challenge for the pharmaceutical industry. Inclusion of lipophilic compound in the hydrophobic core of micelles, i.e. self-assembled structures based on surfactants in aqueous solution, is one way of increasing the solubility. Intravenous formulation of amiodarone hydrochloride with polysorbate 80 as a detergent and benzyl alcohol as a co-solvent is used in medical practice. This paper aimed to study the effect of polysorbate 80 and benzyl alcohol on the water solubility of amiodarone hydrochloride. Formation of mixed micelles consisting of nonionic surfactant polysorbate 80 and cationic amiodarone with chloride counterion was investigated by fluorescence spectroscopy. Benzyl alcohol was found to decrease the stability of the mixed micelles and lead to crystallization of amiodarone hydrochloride. The greatest amounts of crystals formed at 4℃ for 30 days in the model drug solutions with polysorbate 80 concentrations of 100.1 mg/mL and 97.9 mg/mL. A change of the polysorbate 80 concentration and avoidance the use of benzyl alcohol are recommended to improve the stability of the parenteral dosage form. These results can open new perspectives in the optimization of amiodarone intravenous formulations.

Analysis of Microorganisms and Water Transport Properties of the Cotton Fabrics through Dehydration and Drying Process during Washing (세탁의 탈수와 건조과정 중 면직물의 수분전달특성 및 미생물 분석)

  • 최해운;박명자;차옥선
    • The Research Journal of the Costume Culture
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    • v.10 no.5
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    • pp.578-589
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    • 2002
  • The purpose of this research was to analyze the residual water retention and to determine the number and species of microorganisms from the wet cotton fabrics in dehydration and drying process during washing. The drying rates of terrycloth and interlock knit under the rainy seasons were measured according to the dehydration and hanging methods, layers of fabric and pre-treatment agents. Microorganisms were isolated from the dried terrycloth by pure culture, and were identified by Biolog system. The results are as follow: The initial water retention of fabrics after dehydration decreased in the order of dripping>centrifuge>squeezing method, which affected the drying rate. The drying rates were faster by increasing surface area of fabrics. There was no significant difference in drying rate among the fabrics pre-treated with detergent, or fabric softener, or cationic surfactants such as Cetyltrimethylammonium bromide(CTAB) and Benzalkonium chloride(BC). Puedomonas aureginosa was found in the fabrics treated with a powder-type detergent. On the other side, there was no growth of microorganism in the fabrics treated with a liquid-type detergent (containing antibacterial agent), CTAB and BC.

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Development of Genetically Modified Tumor Cell Containing Co-stimulatory Molecule

  • Kim, Hong Sung
    • Biomedical Science Letters
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    • v.25 no.4
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    • pp.398-406
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    • 2019
  • Cancer immunotherapy using gene-modified tumor cells is safe and customized cancer treatment method. In this study, we made gene-modified tumor cells by transferring costimulatory molecules, 4-1BBL and OX40L, into tumor cells using lentivirus vector, and identified anti-cancer effect of gene-modified tumor cells in CT26 mouse colorectal tumor model. We construct pLVX-puro-4-1BBL, -OX40L vector for lentivirus production and optimized the transfection efficiency and transduction efficiency. The transfection efficiency is maximal at DNA:cationic polymer = 1:0.5 and DNA 2 ㎍ for lentivirus production. Then, the lentiviral including 4-1BBL and OX40L was used to deliver CT26 mouse tumor cells to establish optimal delivery conditions according to the amount of virus. The transduction efficiency is maximal at 500 μL volume of lentiviral stock without change in cell shape or growth rate. CT26-4-1BBL, CT26-OX40L significantly inhibited the tumor growth compare with CT26-WT or CT26-β-gal cell line. These data showed the possibility the use of genetically modified tumor cells with costimulatory molecule as cancer immunotherapy agent.

Dye removal from water using emulsion liquid membrane: Effect of alkane solvents on efficiency

  • Ghaemi, Negin;Darabi, Farzaneh;Falsafi, Monireh
    • Membrane and Water Treatment
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    • v.10 no.5
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    • pp.361-372
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    • 2019
  • Effect of different alkane based solvents on the stability of emulsion liquid membrane was investigated using normal alkanes (n-hexane, n-heptane, n-octane and n-decane) under various operating parameters of surfactant concentration, emulsification time, internal phase concentration, volume ratio of internal phase to organic phase, volume ratio of emulsion phase to external phase and stirring speed. Results of stability revealed that emulsion liquid membrane containing n-octane as solvent and span-80 (5 % (w/w)) as emulsifying agent presented the highest amount of emulsion stability (the lowest breakage) compared with other solvents; however, operating parameters (surfactant concentration (5% (w/w)), emulsification time (6 min), internal phase concentration (0.05 M), volume ratio of internal phase to organic phase (1/1), volume ratio of emulsion phase to external phase (1/5) and stirring speed (300 rpm)) were also influential on improving the stability (about 0.2% breakage) and on achieving the most stable emulsion. The membrane with the highest stability was employed to extract acridine orange with various concentrations (10, 20 and 40 ppm) from water. The emulsion liquid membrane prepared with n-octane as the best solvent almost removed 99.5% of acridine orange from water. Also, the prepared liquid membrane eliminated completely (100%) other cationic dyes (methylene blue, methyl violet and crystal violet) from water demonstrating the efficacy of prepared emulsion liquid membrane in treatment of dye polluted waters.

EFFECT OF BENZALKONIUM CHLORIDE ON DENTIN BONDING WITH NTG-GMA/BPDM AND DSDM SYSTEM (Benzalkonium Chloride가 NTG-GMA/BPDM계 및 DSDM계 상아질접착제의 접착성능에 미치는 영향)

  • Shin, Il;Park, Jin-Hoon
    • Restorative Dentistry and Endodontics
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    • v.20 no.2
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    • pp.699-720
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    • 1995
  • This study was conducted to evaluate the effect of benzalkonium chloride solution as a wetting agent instead of water on dentin bonding with NTG-GMA/BPDM system (All-bond 2, Bisco.) and DSDM system (Aelitebond, Bisco.). Benzalkonium chloride solution is a chemical disinfectant widely used in medical and dental clinics for preoperative preparation of skin and mucosa due to its strong effect of cationic surface active detergent. Eighty freshly extracted bovine lower incisor were grinded labially to expose flat dentin surface, and then were acid-etched with 10 % phosphoric acid for 15 second, water-rinsed, and dried for 10 second with air syringe. The specimens were randomly divided into 8 groups of 10 teeth. The specimens of control group were remoistured with water and the specimens of experimental groups were remoistured with 0.1 %, 0.5 %, and 1.0 % benzalkonium chloride solution respectively. And then, the Aelitefil composite resin was bonded to the pretreated surface of the specimens by use of All-bond 2 dentin bonding system or Aelitebond dentin bonding system in equal number of the specimens. The bonded specimens were stored in $37^{\circ}C$ distilled water for 24 hours, then the tensile bond strength was measured, the mode of failure was observed, the fractured dentin surface were examined under scanning electron microscopy, and FT-IR spectroscopy was taken for the purpose of investigating the changes of the dentin surface pretreated with benzal konium chloride solution followed by each primer of the dentin bonding systems. The results were as follows : In the group of bonding with NTG-GMA/BPDM dentin bonding agent(All-bond 2), higher tensile bond strength was only seen in the experimental group remoistured with 0.1 % benzal konium chloride solution than that in water-remoistured control group(p<0.05). In the group of bonding with DSDM dentin bonding agent (Aelitebond), no significant differences were seen between the control and each one of the experimental group(p<0.05). Higher tensile bond strength were seen in NTG-GMAIBPDM dentin bonding agent group than in DSDM dentin bonding agent group regardless of remoistur ization with benzal konium chloride solution. On the examination of failure mode, cohesive and mixed failure were predominantly seen in the group of bonding with NTG-GMAIBPDM dentin bonding agent, while adhesive failure was predominantly seen in the group of bonding with DSDM dentin bonding agent. On SEM examination of fractured surfaces, no differences of findings of primed dentin surface between the groups with and without remoisturization with benzal konium chloride solution. FT-IR spectroscopy taken from the control and the experimental group reve::.led that some higher absorbance derived from the primers binding to dentin surface was seen at the group pretreated with 0.1 % benzal konium chloride solution than at the control group of remoisturizing with water.

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Common features of atopic dermatitis with hypoproteinemia

  • Jo, So Yoon;Lee, Chan-Ho;Jung, Woo-Jin;Kim, Sung-Won;Hwang, Yoon-Ha
    • Clinical and Experimental Pediatrics
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    • v.61 no.11
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    • pp.348-354
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    • 2018
  • Purpose: The purpose of this study was to identify the causes, symptoms, and complications of hypoproteinemia to prevent hypoproteinemia and provide appropriate treatment to children with atopic dermatitis. Methods: Children diagnosed with atopic dermatitis with hypoproteinemia and/or hypoalbuminemia were retrospectively reviewed. The patients' medical records, including family history, weight, symptoms, treatment, complications, and laboratory test results for allergies and skin cultures, were examined. Results: Twenty-six patients (24 boys) were enrolled. Seven cases had growth retardation; 7, keratoconjunctivitis; 6, aural discharges; 5, eczema herpeticum; 4, gastrointestinal tract symptoms; and 2, developmental delays. In 21 cases, topical steroids were not used. According to the blood test results, the median values of each parameter were elevated: total IgE, 1,864 U/mL; egg white-specific IgE, $76.5kU_A/L$; milk IgE, $20.5kU_A/L$; peanut IgE, $30kU_A/L$; eosinophil count, $5,810/{\mu}L$; eosinophil cationic protein, $93.45{\mu}g/L$; and platelet count, $666.5{\times}10^3/{\mu}L$. Serum albumin and total protein levels decreased to 2.7 g/dL and 4.25 g/dL, respectively. Regarding electrolyte abnormality, 10 patients had hyponatremia, and 12, hyperkalemia. Systemic antibiotics were used to treat all cases, and an antiviral agent was used in 12 patients. Electrolyte correction was performed in 8 patients. Conclusion: Hypoproteinemia accompanying atopic dermatitis is common in infants younger than 1 year and may occur because of topical steroid treatment continuously being declined or because of eczema herpeticum. It may be accompanied by growth retardation, keratoconjunctivitis, aural discharge, and eczema herpeticum and can be managed through skin care and topical steroid application without intravenous albumin infusion.

Rheological Properties and Cure Kinetics of Cycloaliphatic/DGEBA Epoxy Blend System Initiated by Cationic Latent Curing Agent (잠재성 경화제를 이용한 Cycloaliphatic/DGEBA계 에폭시 블렌드 시스템의 유변학적 특성 및 경화 동력학)

  • 곽근호;박수진;이재락;김영근
    • The Korean Journal of Rheology
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    • v.10 no.4
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    • pp.227-233
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    • 1998
  • The effects of 1 mol% N-benzylpyrazinium hexafluoroantimonate(BPH) as a thermal latent initiator and blend compositions composed of cycloaliphatic and DGEBA epoxies were investigated in the rheological properties and cure kinetics. Latent properties were performed by measurement of the conversion as a function of reaction time using isothermal DSC at $150^{\circ}C$ and $50^{\circ}C$ Rheological properties of the blend systems were investigated in terms of isothermal experiments using a rheometer. The gelation time was obtained from the evaluation of storage modulus (G'), loss modulus (G") and damping factor (tan$\delta$)). Cross-linking activation energy ($E_c$) was also determined from the Arrhenius equation based on gel time and curing temperature. As a result, the gel time and cross-linking activation energy increased with increasing DGEBA composition. The cure activation energies ($E_a$) were obtained by Kissinger method using dynamic DSC thermograms. In this work, the cure activation energy decreased with increasing CAE concentration, which might be resulted from the short repeat units, simple side-groups and viscosity of reaction media.edia.

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Compatibility of the Recycled Linerboard Made in Acid Sizing System under Neutral or Alkaline Papermaking Conditions (산성 사이징된 재활용 섬유와 중성 사이징의 상용성)

  • Seo, Man Seok;Lee, Kyong Ho;Lee, Hak Lae
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.48 no.2
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    • pp.56-60
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    • 2016
  • Neutral or alkaline papermaking provides many advantages in paper strength and processing conditions. It also provides the opportunity of using calcium carbonate fillers in papermaking. These diverse advantages have made almost all paper machines of printing and writing papers run under neutral and alkaline conditions. On the other hand, linerboard machines, which use recycled papers as a raw material, are running under acid conditions using a rosin sizing system. Because the recycled raw materials used by the linerboard industry contain significant amounts of alkaline papers, the linerboard industry has an interest in the possibility of using the neutral or alkaline papermaking opportunity. In this study, the compatibility of the recycled linerboards under neutral or alkaline papermaking conditions was examined by recycling them under various pH conditions. The sizing degree of the papers recycled under neutral or alkaline was significantly lower than that of acid formed papers indicating that during the neutral or alkaline recycling process the rosin sized papers lost their sizing efficiency. Recycling of acid formed linerboards under neutral or alkaline conditions increased the amount of foam, and the foam contained substantial amount of solid materials derived from the acid sizing systems. Use of cationic polyelectrolytes including PEI and poly-DADMAC improved the sizing degree of the recycled papers under neutral and alkaline conditions. PEI decreased the foam generation as well while poly-DADMAC did not show any reducing effect of the foam. These results suggest that PEI forms coordinate bonds with rosin acid and precipitate them onto the surface of recycled fibers, while the reaction products between poly-DADMAC and rosin acid ions still remain water soluble under neutral or alkaline conditions.

Removal of textile dyes in wastewater using polyelectrolytes containing tetrazole groups

  • Caldera-Villalobos, Martin;Pelaez-Cid, Alejandra-Alicia;Martins-Alho, Miriam-Amelia;Herrera-Gonzalez, Ana-Maria
    • Korean Journal of Chemical Engineering
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    • v.35 no.12
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    • pp.2394-2402
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    • 2018
  • Textile dyes are some of the pollutants which have received the most attention because of the large volume of wastewater generated by the textile industry. Removal by means of adsorption is one of the most versatile alternatives to treat these effluents. Even though different adsorbents such as activated carbons and mineral materials have been proposed, polymeric adsorbents are a viable alternative. This work reports for the first time the use of polyelectrolyte PTZ and macroelectrolyte MTZ containing tetrazole groups as adsorbents useful in the textile dyes removal present in aqueous solutions and wastewater. Because of the anionic character of the tetrazole group, MTZ exhibits selective adsorption capabilities for cationic dyes of up to $156.25mg{\cdot}g^{-1}$. The kinetic study of the process of adsorption shows that PTZ and MTZ fit a pseudo second-order model. MTZ also shows utility as a flocculant agent in the treatment of wastewater containing dyes Indigo Blue and Reactive Black. The results showed that PTZ and MTZ may be used in the treatment of wastewater in a process of coagulation-flocculation followed by the treatment by adsorption. This two-stage treatment removed up to 95% of the dye present in the wastewater. As well as removing the dyes, the values for COD, suspended solids, pH, and color of the wastewater decreased, thus significantly improving its quality.

The Separation of Vanadium and Tungsten from Spent Selective Catalytic Reduction Catalyst Leach Solution by Alamine 336 (탈질 폐촉매 침출액으로부터 Alamine 336에 의한 바나듐과 텅스텐의 분리)

  • Seongsu Kang;Gyeonghye Moon;In-Hyeok Choi;Dakyeong Baek;Kyoungkeun Yoo
    • Resources Recycling
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    • v.33 no.3
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    • pp.30-37
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    • 2024
  • In this study, we investigated the separability of vanadium and tungsten from spent SCR (Selective Catalytic Reduction) catalyst leach solution by reduction of vanadium and solvent extraction using Alamine 336 and conducted experiments to optimize process conditions. It is difficult to separate vanadium and tungsten due to their similar chemical behavior, but tungsten can be selectively extracted from acidic solution when vanadium extraction is prevented by reducing anionic pentavalent vanadium to cationic tetravalent vanadium. The results showed that NaHSO3 was most suitable as a reducing agent, and the extraction efficiency of vanadium decreased and the separation efficiency increased as the amount of reducing agent added, reaction time, and temperature increased. When reducing NaHSO3 1.5 eq, 60 min, and 60℃, which are optimal conditions of reduction, vanadium and tungsten were effectively separated with vanadium extraction efficiency of 5.8%, tungsten extraction efficiency of 99%, and separation factor of vanadium and tungsten of 7,564.