Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 36
Filter
1.
Braz. J. Pharm. Sci. (Online) ; 58: e20243, 2022. graf
Article in English | LILACS | ID: biblio-1403682

ABSTRACT

Abstract In drug therapy, it is important to provide therapeutic levels of drug to the site of action and maintain them during the treatment. This work describes the in vitro release of alendronate from sodium alginate cross-linked Montmorillonite (MMT) composite beads. Effect of crosslinking cation, concentration of montmorillonite and media on encapsulation efficiencies, and release profiles of alendronate were studied. Beads were characterized using equilibrium swelling ability study, Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Energy-dispersive x-ray spectroscopy (EDX) and scanning electron microscopy (SEM). Results indicate that addition of montmorillonite increases the encapsulation efficiencies and slows down the release rates significantly.


Subject(s)
Bentonite/agonists , Alendronate/pharmacology , Alginates/pharmacology , X-Ray Diffraction/methods , In Vitro Techniques/methods , Pharmaceutical Preparations/analysis , Microscopy, Electron, Scanning/methods , Spectroscopy, Fourier Transform Infrared/methods
2.
Braz. J. Pharm. Sci. (Online) ; 58: e21034, 2022. tab, graf
Article in English | LILACS | ID: biblio-1420431

ABSTRACT

Abstract Despite decades of research, wound healing remains a significant public health problem. This study aimed to develop and evaluate a topical sodium alginate gel containing vancomycin (Van) loaded MMT NPs for wound healing applications. Van was loaded in MMT at different conditions (pHs of 6, 7 and temperatures of 40, 50 °C) (Van/MMT NPs). The optimum formulation (with the smallest particle size and a high value of zeta potential; 270.8 ± 77.35 nm and -35.96 ± 2.73, respectively) showed a high drug-loading capacity (entrapment efficacy of 96%) and a sustained release pattern of Van (95%) over 480 min. The optimum Van/MMT NPs were embedded into the sodium alginate (SA) gel (Van/MMT NPs/SA gel). The Van/ MMT NPs/SA gel showed a sustained and slow release pattern of Van (95%) over 50 h. FTIR tests revealed the electrostatic interaction between MMT and Van. The broth macrodilution tube method was used to determine the minimum inhibitory concentration (MIC) of Van, Van/ MMT NPs, and Van/MMT NPs/SA gel against Staphylococcus aureus. The results showed the promising antibacterial activity of Van/MMT NPs/SA gel, thus, this gel can be a promising formulation for the management of infected wounds


Subject(s)
Wound Healing/drug effects , Wound Infection/pathology , Bentonite/antagonists & inhibitors , In Vitro Techniques/methods , Vancomycin/agonists , Alginates/analysis , Wounds and Injuries/drug therapy , Pharmaceutical Preparations/administration & dosage , Spectroscopy, Fourier Transform Infrared/methods , Anti-Bacterial Agents/classification
3.
Braz. J. Pharm. Sci. (Online) ; 58: e21600, 2022. tab, graf
Article in English | LILACS | ID: biblio-1420496

ABSTRACT

Abstract Evaluation of montmorillonite for paraquat by in vitro and in vivo test. In vitro test were evaluated by a batch test, taking the paraquat concentration, adsorbents, reaction environment and time as indices, the absorption rate was screened by orthogonal design. In vivo test was executed with rabbits. Group 1: 4 rabbits dosed with montmorillonite. Group 2: 8 rabbits dosed with 200 mg/kg paraquat. Group 3: 6 rabbits dosed with 200 mg/kg paraquat then gavage with montmorillonite 5 min later. Group 4: 6 rabbits dosed with 200 mg/kg paraquat then gavage with montmorillonite 30 min later. Blood paraquat concentration, serum cytokines, blood gas analysis and histopathology of lung were implemented. In vitro test found that all the four factors influence the absorption rate of paraquat (P < 0.05). In vitro test found that oral montmorillonite could change toxicokinetics parameters of paraquat (P < 0.05); decrease raised serum TGF-ß1 and HMGB1 (P < 0.05) and alleviate the histopathology damage of lung. Montmorillonite might exert its protective effects on paraquat induced damage


Subject(s)
Animals , Male , Rabbits , Paraquat/adverse effects , Poisoning/pathology , Bentonite/agonists , In Vitro Techniques/methods , Blood Gas Analysis , Toxicokinetics
4.
Malaysian Journal of Microbiology ; : 352-360, 2021.
Article in English | WPRIM | ID: wpr-972804

ABSTRACT

Aims@#This research was conducted to develop and characterize polyvinyl alcohol (PVA)/montmorillonite (MONT) clay incorporated with carvacrol (Carva) nanocomposite film as a potential material in wound dressing.@*Methodology and results@#Organophilic MONT clay, which was initially modified from commercial MONT clay by cetyltrimethylammonium bromide (CTAB), was used in the polymerization process using PVA. The synthesized nanocomposites were visualized via transmission electron microscopy (TEM). The developed film (PVA/MONT/Carva nanocomposite film) was characterized via Fourier transform infrared (FTIR). The investigation on mechanical property and antimicrobial activity of the film was also performed. All nanocomposites are spherical, with a size of 92.8 ± 22.1 nm. The -OH stretch, C-H stretch, aromatic group, SiO stretch, and C-O from acetyl group were identified in the PVA/MONT/Carva nanocomposite films. During the chemical release test, carvacrol attained a plateau at 24 h, with a total release of 62.3%. This nanocomposite exhibited a severe detrimental influence on the growth of Gram-bacteria and yeasts, which represented a broad spectrum of antimicrobial agents. All test microorganisms showed approximately up to 82% reduction of microbial growth during the Hohenstein challenge test. Physically, the nanocomposite films were yellowish and apparent. The film was sturdy, flexible, elastic and consisted of excellent water holding capacity.@*Conclusion, significance and impact of study@#PVA/MONT/Carva nanocomposite film may have a useful potential to be merged in the pharmaceutical application, especially in wound dressing production.


Subject(s)
Polyvinyl Alcohol , Bentonite , Wound Healing
5.
Braz. arch. biol. technol ; 63: e20180637, 2020. tab, graf
Article in English | LILACS | ID: biblio-1132189

ABSTRACT

Abstract This study describes the use of bentonite in suspension for the caffeine adsorption (pollutant of emerging concern) by taking different conditions of the pH, adsorbent mass, adsorbent calcination temperature and interferents into account. The results were compared with those obtained using bentonite immobilized in alginate beads. The acid medium has a greater efficiency for the caffeine adsorption and the adsorbent calcination temperature exerts, due to structural changes. Caffeine removal higher than 90% was obtained at optimized conditions. The Langmuir model indicated a better fit of the data and the adsorption capacity of caffeine onto bentonite. The bentonite immobilized led to a slower adsorption process in relation to the suspended.


Subject(s)
Water Pollutants, Chemical/isolation & purification , Bentonite/chemistry , Caffeine/chemistry , Thermodynamics , Caffeine/adverse effects , Adsorption , Environmental Pollutants/isolation & purification , Hot Temperature , Hydrogen-Ion Concentration , Models, Theoretical
6.
Arq. bras. med. vet. zootec. (Online) ; 71(2): 594-602, mar.-abr. 2019. tab
Article in Portuguese | LILACS, VETINDEX | ID: biblio-1011288

ABSTRACT

O objetivo deste trabalho foi avaliar a concentração sérica de cálcio, cloretos, ferro, fósforo e magnésio, as características morfométricas ósseas e a deposição de cálcio e fósforo nas tíbias de frangos de corte recebendo dieta com zero, 0,25 ou 0,50% de bentonita. Um ensaio foi conduzido com 288 frangos de corte de 14 a 21 dias de idade, submetidos a três dietas experimentais: sem inclusão (0,0); com inclusão de 0,25 e com inclusão de 0,50% do adsorvente bentonita. Não foram observadas diferenças (P>0,05) no desempenho das aves, nos níveis séricos de cálcio, cloretos, ferro e magnésio, no entanto os níveis de fósforo foram reduzidos (P<0,05) nas aves que ingeriram dieta com 0,50% de bentonita. Em relação às tíbias, observou-se redução (P<0,05) na matéria mineral (g e %) e no teor de cálcio com a inclusão de 0,50% de bentonita. Houve redução (P<0,05) nos níveis de fósforo das tíbias com a inclusão de 0,25 e 0,50% de bentonita. Conclui-se que a inclusão de até 0,50% do adsorvente de micotoxinas bentonita na dieta de frangos de corte não altera o desempenho zootécnico das aves. A inclusão de 0,25% de bentonita, na dieta de frangos de corte, não altera a concentração dos minerais séricos e a deposição de minerais nas tíbias, entretanto a inclusão de 0,5% reduz os níveis séricos de fósforo, o teor de matéria mineral e a concentração de cálcio e fósforo ósseos, sem afetar as características morfométricas ósseas.(AU)


The aim of this study was to evaluate performance, serum concentration of calcium, chloride, iron, magnesium, phosphorus, and bone characteristics, ash, calcium, and phosphorus in tibias of broilers receiving diet with zero, 0.25 or 0.50% of bentonite. No differences were found on performance of poultry, on serum mineral calcium, chloride, iron, magnesium, however phosphorus levels of broilers fed on diets containing 0.5% bentonite was reduced. With respect to tibia, reduction was observed on mineral matter (g and %) and calcium levels with inclusion of 0.50% bentonite, and reduction on phosphorus levels with inclusion of 0.25 or 0.50% of bentonite on diet. We conclude that the inclusion of up to 0.50% of mycotoxin adsorbent bentonite in diet of broiler does not change broiler performance. The inclusion of 0.25% of bentonite in diet of broiler does not change serum mineral concentration and mineral deposition; however, the inclusion of 0.5% decrease serum levels of phosphorus, the content of bone mineral matter, with not effects on bone morphometric characteristics.(AU)


Subject(s)
Animals , Male , Bentonite/administration & dosage , Bentonite/therapeutic use , Bone Development , Antitoxins/administration & dosage , Chickens/growth & development , Diet/veterinary , Food Additives/therapeutic use , Animal Feed , Minerals/analysis , Minerals/blood , Chickens/microbiology
7.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 213-215, 2015.
Article in Chinese | WPRIM | ID: wpr-326032

ABSTRACT

<p><b>OBJECTIVE</b>To explore the clinical efficacy of early application of sequential gastrointestinal lavage in patients with acute paraquat poisoning by analyzing the clinical data of 97 patients.</p><p><b>METHODS</b>A total of 97 eligible patients with acute paraquat poisoning were divided into conventional treatment group (n = 48) and sequential treatment group (n = 49). The conventional treatment group received routine gastric lavage with water. Then 30 g of montmorillonite powder, 30 g of activated charcoal, and mannitol were given to remove intestinal toxins once a day for five days. The sequential treatment group received 60 g of montmorillonite powder for oral administration, followed by small-volume low-pressure manual gastric lavage with 2.5%bicarbonate liquid. Then 30 g of activated charcoal, 30 g of montmorillonite powder, and polyethylene glycol electrolyte lavage solution were given one after another for gastrointestinal lavage once a day for five days. Both groups received large doses of corticosteroids, blood perfusion, and anti-oxidation treatment. The levels of serum potassium, serum amylase (AMY) alanine aminotransferase (ALT), total bilirubin (TBIL), blood urea nitrogen (BUN), creatinine (Cr), lactate (Lac), and PaO₂of patients were determined at 1, 3, 5, 7, and 10 days. Laxative time, mortality, and survival time of dead cases were evaluated in the two groups.</p><p><b>RESULTS</b>The incidence rates of hypokalemia (<3.5 mmol/L) and AMY (>110 U/L) were significantly lower in the sequential treatment group than in the conventional treatment group (P < 0.05). There were no significant differences in the incidence of ALT (>80 U/L), TBIL (>34.2 µmol/L), BUN (>7.2 mmol/L), and Cr (>177 µmol/L) between the two groups (P>0.05). However, the highest levels of ALT, TBIL, BUN, Cr, and Lac were significantly lower in the sequential treatment group than in the conventional treatment group (P < 0.05). Moreover, the sequential treatment group had significantly lower incidence of PaO₂(<60 mmHg), shorter average laxative time, lower mortality, and longer survival time of dead cases than the conventional treatment group (P < 0.05).</p><p><b>CONCLUSION</b>The early application of sequential gastrointestinal lavage can shorten laxative time, alleviate organ damage in the liver, kidney, lung, and pancreas, reduce mortality, and prolong the survival time of dead cases in patients with acute paraquat poisoning.</p>


Subject(s)
Humans , Acute Disease , Bentonite , Bilirubin , Blood Urea Nitrogen , Charcoal , Combined Modality Therapy , Creatinine , Gastric Lavage , Methods , Liver , Paraquat , Poisoning , Poisoning , Therapeutics , Treatment Outcome
8.
Braz. j. pharm. sci ; 48(4): 609-619, Oct.-Dec. 2012. ilus, tab
Article in English | LILACS | ID: lil-665857

ABSTRACT

The objective of the present investigation was to develop bilayered tablets of lornoxicam to achieve biphasic release pattern. A bilayered tablet, consisting of an immediate and controlled release layer, was prepared by direct compression technique. The controlled release effect was achieved by using various hydrophilic natural, semi synthetic and synthetic controlled release polymers such as xanthan gum, hydroxypropyl methylcellulose (HPMC) and polyethylene oxide (PEO) to modulate the release of the drug. The in vitro drug release profiles showed the biphasic release behavior in which the immediate release (IR) layer containing the lornoxicam was released within 15 minutes, whereas the controlled release (CR) layer controlled the drug release for up to 24 h. All the bilayered tablets formulated have followed the zero order release with non-Fickian diffusion controlled release mechanism after the initial burst release. FTIR studies revealed that there was no interaction between the drug and polymers used in the study. Statistical analysis (ANOVA) showed no significant difference in the cumulative amount of drug release after 15 min, but significant difference (p < 0.05) in the amount of drug released after 24 h from optimized formulations was observed. Based on the release kinetic parameters obtained, it can be concluded that xanthan gum polymer was suitable for providing a biphasic release of lornoxicam.


O objetivo do presente trabalho foi desenvolver comprimidos bicamada de lornoxicam para atingir padrão de liberação bifásica. Preparou-se, por compressão direta, comprimido bicamada, consistindo de uma camada de liberação imediata e uma de liberação controlada. A liberação controlada foi obtida pelo uso de vários polímeros naturais hidrofílicos, semi-sintéticos e sintéticos, tais como goma xantana, hidroxipropilmetil celulose (HPMC) e óxido de polietileno (PEO) para modular a liberação do fármaco. Os perfis de liberação in vitro mostraram comportamento bifásico em que a camada de liberação imediata (IR) contendo lornoxicam foi liberada em 15 minutos, enquanto a camada de liberação controlada (CR) liberou o fármaco em mais de 24 horas, Todos os comprimidos bicamada formulados seguiram a liberação de ordem zero com mecanismo de liberação controlada por difusão não fickiana após a liberação inicial por erupção. Os estudos de FTIR revelaram que não há interação entre o fármaco e os polímeros utilizados no estudo. A análise estatística (ANOVA) não mostrou diferença significativa na quantidade acumulada de fármaco após 15 minutos de liberação, mas observou-se diferença significativa (p<0,05) na quantidade de fármaco liberado após 24 h nas formulações otimizadas. Com base nos parâmetros de cinética de liberação obtidos, pode-se concluir que a goma xantana foi adequada para se atingir liberação bifásica de lornoxicam.


Subject(s)
Tablets/pharmacokinetics , Bentonite/antagonists & inhibitors , Polymers/pharmacokinetics , Drug Liberation
9.
China Journal of Chinese Materia Medica ; (24): 781-784, 2012.
Article in Chinese | WPRIM | ID: wpr-288707

ABSTRACT

<p><b>OBJECTIVE</b>To optimize a simple and effective method for total RNA extraction from bulblet of Fritillaria anhuiensis.</p><p><b>METHOD</b>Four methods, i. e. guanidine isothiocyanate, bentonite, modified SDS/phenol and the RNAiso plus, were used to extract total RNA from bulblet of F. anhuiensis. Then the results of the extraction were compared and analyzed by electrophoresis detection and RT-PCR verification.</p><p><b>RESULT</b>The total RNA extracted by bentonite method were clear and no dispersion, the integrity of the RNA was well, and there was no obvious contamination with DNA and other impurities, was suitable for RT-PCR test.</p><p><b>CONCLUSION</b>The bentonite method is quick, economic, and efficient for total RNA extraction from bulblet of F. anhuiensis.</p>


Subject(s)
Bentonite , Chemistry , DNA, Complementary , Electrophoresis , Fritillaria , Genetics , Guanidines , Chemistry , Isothiocyanates , Chemistry , Phenol , Chemistry , Plant Roots , Genetics , Plants, Medicinal , Genetics , RNA, Plant , Reverse Transcriptase Polymerase Chain Reaction , Sodium Dodecyl Sulfate , Chemistry , Time Factors
10.
Journal of Zhejiang University. Medical sciences ; (6): 631-638, 2012.
Article in Chinese | WPRIM | ID: wpr-336742

ABSTRACT

<p><b>OBJECTIVE</b>To develop polyethylenimine-Doxorubicin-montmorillonite (PEI-Dox-MTT) as a novel multifunction delivery system.</p><p><b>METHODS</b>Dox was intercalated into montmorillonite, PEI covered to the surface of Dox/MMT to make the nano-particle. XRD, FT-IR and TGA were used to confirm chemical property of the nano-particle. SEM was used to observe the morphology. The capability of drug release was investigated by PBS buffer solution (pH 7.4). The DNA binding ability of nano-particle was detected by gel electrophoresis retardation assay. The cell viability in COS-7 and SKOV3 cell lines was tested using MTT assay. The gastric mucosa protection was evaluated in vitro.</p><p><b>RESULTS</b>XRD image showed that Dox was intercalated into montmorillonite, inter space of which increased to 31.3Å; the FT-IR spectra showed the vibration bands of PEI at 1 560 cm(-1) and 2 850 cm(-1), the vibration band of Dox at 1 350 cm(-1). Size analysis and SEM revealed that the size of nano-particle was 600 nm, and the zeta-potential was 30 mV. Drug release experiment explored that the nano-particle stably released drug in range of 6 X10(-4) ≊ 8 X10(-4) mg/ml within 72 h. MTT assay showed that the cell viability was over 80% in experiment condition in COS-7 and SKOV3 cell lines. 0.3 mg PEI-MMT nano-particle was able to protect gastric mucosa from alcohol.</p><p><b>CONCLUSION</b>Multifunction system of PEI/Dox/MMT has been prepared successfully.</p>


Subject(s)
Humans , Bentonite , Cell Line , Doxorubicin , Drug Delivery Systems , Genetic Vectors , Polyethyleneimine
11.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 914-917, 2010.
Article in Chinese | WPRIM | ID: wpr-293791

ABSTRACT

<p><b>OBJECTIVE</b>To study the genotoxicity induced by organic bentonite particles in vitro.</p><p><b>METHODS</b>Human B lymphoblast cells (HMy2.CIR) were exposed to organic bentonite particles at the doses of 0, 1.88, 3.75, 7.50 and 15.00 µg/ml for 24, 48 and 72 h, calcium sulfate (30 µg/ml) and SiO2 (30 and 240 µg/ml) served as negative and positive controls, respectively. The genotoxicity of organic bentonite particles and soluble fraction was detected using comet assay and Cytokinesis-block micronucleus (CBMN) assay.</p><p><b>RESULTS</b>The results of comet assay indicated that % tail DNA increased with the exposure doses and time in organic bentonite group, % tail DNA at the dose of 15.00 µg/ml for 24 h, 48 h and 72 h in organic bentonite group were 3.20 ± 0.19, 4.63 ± 0.88 and 9.49 ± 1.31 respectively which were significantly higher than those in calcium sulfate group (1.40 ± 0.11, 1.37 ± 0.22 and 0.90 ± 0.16) and those in 30 µg/ml SiO2 group (1.83 ± 0.21, 1.41 ± 0.27 and 2.48 ± 0.25) (P < 0.01). The results of CBMN assay showed that micronucleus frequencies (MNF) in organic bentonite group (except for 1.88 µg/ml for 24 h) were significantly higher than those in 30 µg/ml calcium sulfate group (MNF for 24, 48 and 72 h were 1.33‰ ± 0.58‰, 1.33‰ ± 1.15‰ and 1.33‰ ± 0.58‰) and those in 30 µg/ml SiO2 group (2.00‰ ± 0.00‰, 1.68‰ ± 0.58‰ and 2.33‰ ± 0.58‰) (P < 0.01). The results of two assays demonstrated that the soluble fraction of organic bentonite did not induce the genotoxicity.</p><p><b>CONCLUSION</b>The organic bentonite dusts can induce the genotoxicity in vitro, which may be from the particle fraction.</p>


Subject(s)
Humans , Bentonite , Toxicity , Cells, Cultured , Comet Assay , DNA Damage , Lymphocytes , Micronucleus Tests , Mutagenicity Tests , Quartz , Toxicity
12.
Armaghane-danesh. 2009; 14 (1): 13-23
in Persian | IMEMR | ID: emr-101280

ABSTRACT

Over the past decade the US army has widely studied new technologies for stopping sever hemorrhages and has introduced an effective Zeolite based hemostatic agent. On the other hand, Mortazavi and his colleagues previously reported the bio-stimulatory effects of the topical application of radioactive lantern mantle powder on wound healing. Their subsequent studies showed significant changes in some histological parameters concerning healing. In this light, here the bio-stimulatory effect of burned radioactive lantern mantles powder as well as two minerals; bentonite and zeolite arepresented. This experimental study was conducted in the center for radiological studies, Shiraz university of Medical Sciences in 2008. Fifty male Wistar rats were divided randomly into 5 groups of 10 animals each. Following anesthesia, animals' tails were cut at a thickness of 5 mm by using a surgical scissor. No intervention was made on the animals of the 1[st] group. The 2[nd] group to 4[th] group received topical non-radioactive lantern mantle powder, radioactive lantern mantle powder, Bentonite mineral or a mixture of Bentonite-Zeoliteat minerals respectively. After treatment with above mentioned agents, the volume of blood loss was measured using a scaled test-tube. The bleeding time and clotting time were also measured using a chronometer. SPSS software was used for statistical analysis. ANOVA was used for comparing the means of each parameter in the 5 groups. The volume of blood loss, bleeding and clotting times in control animals were 4.39 +/- 1.92 cc, 112.10 +/- 39.60 sec and 94.9 +/- 54.26 sec, respectively. In the 5[th] group in which the animals were treated with a mixture of Bentonite-Zeoliteat minerals, the volume of blood loss, bleeding and clotting times were 1.31 +/- 0.60 cc, 34.50 +/- 4.65 sec and 24.2 +/- 4.61 sec, respectively. This is the 1[st] investigation that studied the alterations of bleeding and clotting times following the use of lantern mantle powder as well as bentonite or the mixture of bentonite-zeolite minerals. The results obtained in this study clearly show the significant effect of the volume of blood loss as well as the bleeding time following the topical use of the mixture of bentonite-zeolite minerals. The radioactive and non-radioactive lantern mantle and the bentonite mineral alone had considerable effects but overally the magnitude of the effect was less than that of the mixture of bentonite-zeolite minerals


Subject(s)
Male , Animals , Zeolites , Bentonite , Hemorrhage , Bleeding Time , Blood Coagulation/radiation effects , Minerals , Rats, Wistar
13.
Chinese Journal of Industrial Hygiene and Occupational Diseases ; (12): 338-340, 2009.
Article in Chinese | WPRIM | ID: wpr-352890

ABSTRACT

<p><b>OBJECTIVE</b>To study comparatively the cytotoxicity induced by acid bentonite and organic bentonite.</p><p><b>METHODS</b>The cytotoxicity of two kinds of bentonite was detected using CCK8 assay, neutral red uptake (NRU) assay, lactate dehydrogenase (LDH) leakage assay, apoptosis assay and hemolysis assay. In hemolysis assay human erythrocytes served as target cells and were exposed to the two kinds of bentonite at the doses of 0, 0.3125, 0.6250, 1.2500 and 2.5000 mg/ml for ten min. In other four assays, human B lymphoblast cells (HMy2.CIR) served as target cells and were exposed to the two kinds of bentonite at the doses of 0, 10, 20, 30, 60, 120 and 180 microg/ml for four h.</p><p><b>RESULTS</b>In hemolysis assay, the hemolysis rates induced by two kinds of bentonite at all doses were significantly higher than that of control (P<0.05); in CCK-8 assay, the cellular activities in acid bentonite group at the doses > or =30 microg/ml and in organic bentonite group at the doses > or =20 microg/ml were significantly lower than that of control (P<0.01); the similar results appeared in NRU assay and LDH assay, and the dose-effect relationship was observed in above 4 assays. In apoptosis assay, the early apoptosis cell rates in acid bentonite group at the dose of 180 microg/ml and in organic bentonite group at the doses of 120,180 microg/ml were significantly higher than that of control (P<0.05). Moreover, the results of five in vitro assays indicated the cytotoxicity induced by organic bentonite was higher than that induced by acid bentonite.</p><p><b>CONCLUSION</b>Two kinds of bentonite could induce cytotoxicity, such as apoptosis and damage of cell membrane. The cytotoxicity of organic bentonite is higher than that of acid bentonite due to the different industrial treatment and characteristics of two kinds of bentonite particles.</p>


Subject(s)
Humans , Apoptosis , Bentonite , Toxicity , Cell Line , Cytotoxicity Tests, Immunologic , Erythrocytes , Pathology , Hemolysis , Lymphocytes , Pathology
14.
Rev. ciênc. farm. básica apl ; 29(2): 149-158, 2008. tab, graf
Article in Portuguese | LILACS | ID: lil-514284

ABSTRACT

O presente estudo avaliou sistemas baseados em bentonita sódica purificada e bentonita sódica purificada intercalada com colina como promotores de dissolução de clorpropamida. A intercalação da bentonita sódica foi avaliada por difração de raios X, análise termo gravimétrica, análise calorimétricade varredura e espectrometria no infravermelho. Prepararam-se misturas físicas, empastamentos (kneadings) e granulados e comprimidos, por granulação úmida e compressão direta; ambos os sistemas (físicos e comprimidos) com diversas relações fármaco: promotores de dissolução. Todos os sistemas físicos e os comprimidos foram avaliados quanto à dissolução do fármaco segundo metodologia descrita na Farmacopéia Norte-Americana (USP). Os comprimidos ainda foram avaliados quanto à dureza e friabilidade. O empastamento hidroalcoólico mostrou ser o melhor sistema físico para aumento da dissolução, entretanto é inviável para produção industrial de comprimidos. Os comprimidos de clorpropamida preparados por granulação úmida com proporção de fármaco e promotores de dissolução de 1:0,25 p/p apresentaram melhores resultados no teste de dissolução em relação aos comprimidos sem os promotores. Não houve diferença significativa entre a liberação de clorpropamida com a bentonita sódica e bentonita sódica intercalada. Os comprimidos preparados por compressão direta apresentaram, comparativamente, o melhor desempenho no teste de dissolução. Não foi evidenciado perda de cristalinidade do fármaconos sistemas estudados. O poder de desintegração da bentonita e a possível interação molecular entre o fármaco e a bentonita são as prováveis causas do aumento da dissolução da clorpropamida com tais sistemas baseados em bentonita.


Subject(s)
Bentonite/pharmacology , Chlorpropamide/pharmacokinetics , Tablets
15.
Egyptian Journal of Chemistry. 2008; 51 (6): 763-776
in English | IMEMR | ID: emr-126447

ABSTRACT

The adsorption of phenol, p- nitrophenol and p- cresol from their aqueous solution onto Na-bentonite was investigated at 30[degree sign], 40[degree sign] and 50 [degree sign] C and at different pH ranging from 1.5 to 8.3. Kinetic adsorption results were obtained at 30[degree sign] C and pH 6.5. The data obtained were analyzed considering pseudo- first and pseudo-second order kinetic models. The intraparticle diffusion model was also considered to determine the diffusion process controlling the adsorption of the phenols investigated. Equilibrium adsorption isotherms were also achieved and analyzed considering both langmuir and Freundlich equations. The thermodynamic parameters were calculated and discussed. The adsorption of the investigated phenols increased with the increase of pH from 1.5 to exhibit a maximum at pH 6.5. The kinetic experiments indicated that about 95% of the adsorption was completed after 5 hr. The pseudo- second order kinetic model was more applicable to the kinetic adsorption results. The adsorption decreased with the rise of adsorption temperature. Generally, the highly soluble phenol measured the lowest adsorption capacity. The function group in the para position affected also the adsorption. The thermodynamic parameters delta G, delta h and delta S were all negative indicating the feasibility of the adsorption process


Subject(s)
Cresols/chemistry , Adsorption , Bentonite , Thermodynamics
16.
Article in English | IMSEAR | ID: sea-114125

ABSTRACT

The study was carried out to understand the interaction of Zinc (II), which happens to be an essential micronutrient and essential element for all life, with a mineral surface, Montmorillonite Clay which happens to be an important soil constituent and is compared with carbonaceous solid phase such as Activated Carbon. It was found that retention takes place through chemisorptions, ion exchange and probably precipitation also involved at higher pH. The effect of various parameters such as pH, contact time, adsorbent dosage and initial concentration of the metal ion on the kinetics of adsorption was studied. At higher pH of the clay system, zinc becomes less soluble. The adsorption behaviour of zinc using a blend of Montmorillonite Clay, Activated Carbon was also studied. It was found that when the percentage of Activated Carbon in the blend increases, the percentage retention decreases. The release of Zn (II) was studied using different extracting solutions. The desorption was insignificant indicating the possibility of formation of inner sphere complexes. The adsorption data was also applied to the effluent from Zinc Smelting Industry.


Subject(s)
Adsorption , Aluminum Silicates , Bentonite/chemistry , Carbon/chemistry , Chromatography, Ion Exchange , Environmental Monitoring/instrumentation , Hydrogen-Ion Concentration , Hydrolysis , Kinetics , Metals/chemistry , Time Factors , Zinc/chemistry
17.
Acta Pharmaceutica Sinica ; (12): 318-322, 2007.
Article in Chinese | WPRIM | ID: wpr-281900

ABSTRACT

The aims of this study were to prepare Cu(2+)-loaded montmorillonite (Cu-MMT) and investigate its bactericidal activity and mechanism. Cu-MMT was prepared by the method of ion exchange reaction. The structure and surface characteristic of Cu-MMT were determined. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Cu-MMT against the strain of Escherichia coli were determined. The activities of intracellular enzyme in bacterial solution were measured, and the morphology of E. coli was observed during the interaction between Cu-MMT and bacteria. The results showed that treatment with Cu2+ increased cation exchange capacity of montmorillonite, but specific surface area and surface negative charge density were decreased. The MIC and MBC of Cu-MMT against the tested E. coli were 0.16 and 0.64 mg x m(L(-1), respectively. Cu-MMT could destroy bacterial cellular membrane and then resulted in leakage of intracellular enzymes such as asparate aminotransferase, lactate dehydrogenase and alanine aminotransferase. These suggest that Cu-MMT has a strong bactericidal activity. The bactericidal mechanism of Cu-MMT may be that bacteria are adsorbed by Cu-MMT, and then morphology and permeability of cellular membrane are changed. This leads to an efflux of intracellular contents and the death of bacteria.


Subject(s)
Alanine Transaminase , Metabolism , Anti-Bacterial Agents , Chemistry , Pharmacology , Aspartate Aminotransferases , Metabolism , Bentonite , Chemistry , Pharmacology , Copper , Chemistry , Pharmacology , Drug Compounding , Escherichia coli , Escherichia coli Proteins , Metabolism , L-Lactate Dehydrogenase , Metabolism , Microbial Sensitivity Tests
18.
Journal of Zhejiang University. Science. B ; (12): 314-319, 2006.
Article in English | WPRIM | ID: wpr-251919

ABSTRACT

Bentonite is a kind of natural clay with good exchanging ability. By exchanging its interlamellar cations with various soluble cations, such as quaternary ammonium cations and inorganic metal ions, the properties of natural bentonite can be greatly improved. In this study, hexadecyltrimethylammonium bromide (HDTMA), CaCl(2), MgCl(2), FeCl(3), AlCl(3) were used as organic and inorganic pillared materials respectively to produce several kinds of Ca-, Mg-, Fe-, Al-organo pillared bentonites. Sorption of reactive red X-3B on them was studied to determine their potential application as sorbents in wastewater treatment. The results showed that these pillared bentonites had much improved sorption properties, and that the dye solutions' pH value had some effect on the performance of these inorgano-organo pillared bentonites. Isotherms of reactive X-3B on these pillared bentonites suggested a Langmuir-type sorption mechanism.


Subject(s)
Aluminum Compounds , Chemistry , Bentonite , Chemistry , Calcium Chloride , Chemistry , Cations , Cetrimonium Compounds , Chemistry , Chlorides , Chemistry , Coloring Agents , Chemistry , Ferric Compounds , Chemistry , Hydrogen-Ion Concentration , Magnesium Chloride , Chemistry , Naphthalenes , Chemistry , Triazines , Chemistry , Waste Disposal, Fluid , Methods , Water Pollutants, Chemical
19.
Bulletin of the National Research Centre. 2005; 30 (4): 377-389
in English | IMEMR | ID: emr-70275

ABSTRACT

The miocene clay deposits at G. Hamza- G. Um Qamar off the Cairo Ismailia Road are texturally classified as silt bearing, clay-rich mudstones. X-Ray powder diffraction analysis indicates that the main clay minerals present are montmorillonite and kaolinite. Urn Qamar mudstones contain higher percentages of montmorillonite and lower proportions of Kaoloinite than those of G. Hamza. The IR absorption bands of these clay minerals in the OH and Si-O stretching regions, as well as those in the OH and Si-O bending regions have been studied in detail. The FTIR analysis indicates that Mg[II] and Fe [II] are present in minor amounts in the montmorillonite structure


Subject(s)
Spectroscopy, Fourier Transform Infrared , Bentonite/chemistry , Kaolin/chemistry , Magnesium/chemistry , Iron/chemistry , Soil/analysis
20.
J Biosci ; 2003 Feb; 28(1): 115-9
Article in English | IMSEAR | ID: sea-111182

ABSTRACT

A simple, fast, precise and biologically relevant toxicity assay for screening cytotoxicity of minerals would have distinct advantages due to its cost benefits and relative savings in time. Furthermore, a bioassay to differentiate acute and chronic in vivo pulmonary reactions could have potential value as predictors of fibrogenicity and pathogenicity. In this study we examined the potential use of lucigenin as a probe to evaluate the correlation between chemiluminescence (CL) generated by alveolar macrophages with the known cytotoxicity and patho genicity by conventional bioassays. In this study, we used small doses of dust (20 microg) to minimize cellular overload and to maintain homeostasis. Crystalline silica a highly fibrogenic dust was used as positive control and results are compared with those for bentonite, kaolin and talc. Among the three minerals compared with silica, bentonite was more reactive (27%) in CL assay and declined sharply compared to other minerals. This sudden decline in bentonite CL is caused by cytotoxicity leading to cell death. CL-induced by talc was comparable to silica and declines slowly. Kaolin on the other hand produced relatively a weaker (25%) CL compared to silica. Our data using relatively low doses of dust suggest that the CL assay may have a better predictive value in cytotoxicity evaluations compared to conventional toxicity assays.


Subject(s)
Acridines/metabolism , Animals , Bentonite/toxicity , Bronchoalveolar Lavage Fluid/cytology , Cell Survival/drug effects , Cells, Cultured , Luminescent Measurements , Dust/analysis , Feasibility Studies , Inflammation , Kaolin/toxicity , Kinetics , Macrophages, Alveolar/drug effects , Male , Minerals/toxicity , Models, Biological , Predictive Value of Tests , Quartz/toxicity , Rats , Talc/toxicity
SELECTION OF CITATIONS
SEARCH DETAIL