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1.
Gels ; 9(11)2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37998955

RESUMO

The L-cysteine-functionalized silica (SG-Cys-Na+) matrix was effectively loaded with silver (I) ions using the batch sorption technique. Optimal Ag(I) loading into SG-Cys-Na+ reached 98% at pHi = 6, 80 rpm, 1 mg L-1, and a temperature of 55 °C. The Langmuir isotherm was found to be suitable for Ag(I) binding onto SG-Cys-Na+ active sites, forming a homogeneous monolayer (R2 = 0.999), as confirmed by FTIR spectroscopy. XRD analysis indicated matrix stability and the absence of Ag2O and Ag(0) phases, observed from diffraction peaks. The pseudo-second-order model (R2 > 0.999) suggested chemisorption-controlled adsorption, involving chemical bonding between silver ions and SG-Cys-Na+ surface. Thermodynamic parameters were calculated, indicating higher initial concentrations leading to increased equilibrium constants, negative ΔG values, positive ΔS values, and negative ΔH. This study aimed to explore silver ion saturation on silica surfaces and the underlying association mechanisms. The capability to capture and load silver (I) ions onto functionalized silica gel materials holds promise for environmental and water purification applications.

2.
Molecules ; 27(3)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35164120

RESUMO

This study aimed to evaluate the antioxidant activity and total phenolic content (TPC) and total flavonoid content (TFC) of crude extracts obtained from three Asclepiadaceae species, namely, Calotropis procera L., Peruglaria tomentosa L., and Pentatropis spiralis (Forsk.) Decne. Both butanol and aq. methanol extracts of the three species showed the highest amount of phenol and flavonoid contents, which exhibited the greatest antioxidant activity in the scavenging of 2,2-diphenyl-2-picrylhydrazyl free radical (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt radical cation (ABTS), ferrous chelating effect (FIC), and hydroxyl radical (HDR) assays. Phytochemical screening of the extracts revealed the presence of alkaloids, tannins, sponins, flavonoids, terpenoids, and glycosides. LC-MS analysis was carried out to identify the major compounds from each crude extract. A total of 12 phenolic compounds in the extracts of the 3 species were identified and quantified, including 9 flavonoids, 2 hydroxybenzoic acids, and 3 hydroxycinnamic acids. The current study also revealed a good correlation between total phenolic contents and the observed antioxidant activity of the crude extracts.


Assuntos
Antioxidantes/análise , Apocynaceae/química , Flavonoides/análise , Extratos Vegetais/química , Folhas de Planta/química , Apocynaceae/crescimento & desenvolvimento , Cromatografia Líquida , Jordânia , Folhas de Planta/crescimento & desenvolvimento , Especificidade da Espécie , Espectrometria de Massas em Tandem
3.
Sci Prog ; 104(2): 368504211026162, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34152891

RESUMO

The aim of this study is to compare the elemental composition among different coffee varieties consumed in Jordan. Levels of different metallic elements in coffee samples; green and roasted coffee beans from five origins; Brazil, Ethiopia, Kenya, Columbia, and India, collected from the Jordanian market were investigated. Twenty-two elements, including essential and toxic elements such as potassium (K), magnesium (Mg), calcium (Ca), iron (Fe), aluminum (Al), manganese (Mn), copper (Cu), barium (Ba), strontium (Sr), zinc (Zn), chromium (Cr), lead (Pb), nickel (Ni), vanadium (V), cobalt (Co), gallium (Ga), uranium (U), cadmium (Cd), silver (Ag), lithium (Li), indium (In), bismuth (Bi), thorium (Th), and thallium (Ti), were determined using inductively coupled plasma-mass spectrometry (ICP-MS). The detected heavy metals and their intake per 1 cup of coffee did not largely contribute to the recommended daily intake (RDI) and tolerable upper limit of daily intake (TULD) in an adult with an average body weight of 80 kg. The ICP-MS versus flame atomic absorption spectrometry (FAAS) results were linearly fitted, and the correlation coefficients (R2 > 0.95) were better than 0.95 for the three checked elements. No significant difference between the results of the two techniques was observed (p > 0.05). The ANOVA results indicated the presence of a significant difference between the levels of Cr, Co, and Zn in green and roasted coffee beans. The results of this study indicated that the coffee consumed in Jordan did not contain toxic levels of heavy elements and is safe for consumption according to health organizations.


Assuntos
Café , Metais Pesados , Cromo/análise , Cobalto/análise , Café/química , Metais Pesados/análise , Espectrofotometria Atômica
5.
Arch Environ Contam Toxicol ; 55(4): 558-65, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18351413

RESUMO

Wet and dry deposition samples were collected in a rural region in northern Jordan during the period of December 1998 to April 2000. Concentrations of 20 chemical species (Na, K, Ca, H(+), Mg, NH(4)(+), Cl(-), NO(3)(-), SO(4)(2-), Pb, Cd, Zn, Cu, Al, Fe, Mn, Mo, Ni, Sb, and V) were determined in collected samples. Most of the Al, Fe, Mn, Mo, Sb, and V were not soluble, whereas major ions (Na, K, Ca, H(+), Mg, NH(4)(+), Cl(-), NO(3)(-), and SO(4)(2-) ) and some trace elements (Cd, Cu, and Zn) were wet deposited mostly in the soluble form. Concentration of the soil-related elements and/or highly soluble species were washed out at the early stages of a precipitation event, and their concentrations were mostly controlled by dilution, whereas concentrations of anthropogenic species were controlled by other factors. Annual fluxes of the soil-related elements and ions were significantly higher than the primarily anthropogenic elements. This was attributed to the arid nature of the region and to the frequent input of the Saharan dust pulses.


Assuntos
Poluentes Atmosféricos/análise , Clima Desértico , Monitoramento Ambiental/métodos , Metais Pesados/análise , Chuva , Oligoelementos/análise , Monitoramento Ambiental/estatística & dados numéricos , Jordânia , População Rural/estatística & dados numéricos , Poluentes do Solo/análise
6.
Environ Monit Assess ; 136(1-3): 209-18, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17370132

RESUMO

Wet and dry deposition samples were collected in the capital of Jordan, Amman. Concentrations of Al, Ba, Bi, Cd, Co, Cr, Cu, Mn, Mo, Ni, Pb, Sb, V, Zn, Fe, Sr, Mg2+, Ca2+, Na+, K+, Cl-, NO3- and SO(4)(2-), along with pH were determined in collected samples. Mean trace metal concentrations were similar or less than those reported for other urban regions worldwide, while concentrations of Ca2+ and SO(4)(2-) were among the highest. High Ca2+ concentrations were attributed to the calcareous nature of the local soil and to the influence of the Saharan dust. However, high SO(4)(2-) concentrations were attributed to the influence of both anthropogenic and natural sources. Except for Cl-, NO3-, SO(4)(2-) and Cu, monthly dry deposition fluxes of all measured species were higher than wet deposition fluxes. The annual wet deposition fluxes of trace metals were much lower than those reported for other urban areas worldwide.


Assuntos
Atmosfera/química , Elementos Químicos , Poluentes Ambientais/análise , Metais/análise , Monitoramento Ambiental , Humanos , Jordânia , Controle de Qualidade
7.
Biol Trace Elem Res ; 115(2): 157-67, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17435259

RESUMO

Analysis and distribution of Pb and Cd in different mice organs, including the liver, kidney, spleen, heart, and blood, were evaluated before and after treatment with different aqueous concentrations of Nigella sativa (1.25-10.0 mg/L). Atomic absorption spectrometry was used for analysis of Pb and Cd in these organs. Results indicated that the Pb in the unexposed group of mice without treatment with N. sativa (black cumin) was in the following order: liver > heart > spleen > kidney, and the distribution of Pb in various organs of the unexposed group was not affected significantly by N. sativa. Moreover, results of mice exposed for Pb show that the Pb concentrations in different organs were reduced significantly (p < 0.05) by 72.9%, 63.4%, 72.3%, 66.7%, and 39.5% at a dose of 10 mg/L of N. sativa for the liver, kidney, heart, spleen, and blood, respectively. Furthermore, the distribution of Cd in the unexposed Cd group of mice without treatment with N. sativa was in the following order: kidney > heart > spleen > liver. Nigella sativa at 10 mg/L reduced Cd levels in mice exposed to Cd by 75.5%, 83.3%, 47.0%, 95.3%, and 100% in the liver, kidney, heart, spleen, and blood, respectively, whereas blood Cd concentrations were lowered to below the detection limit of 0.05 mug/L. A 28-d exposure of mice to a Cd-Pb mixture at a concentration of 1 ppm in drinking water induced a highly significant inhibition (p < 0.0001) of antibody response to human serum (80.5%). The suppressed immune responses in mice pretreated with the Cd-Pb mixture were reversed by 43.1% and 38.9% in the presence of 1.25 and 2.5 mg/mL of N. sativa, respectively, whereas higher concentrations (5-10 mg/mL) of N. sativa increased the immunosuppression significantly. Nigella sativa at 1.25-10 mg/mL did not induce any significant modulation of the antibody response in unexposed mice.


Assuntos
Cádmio/farmacocinética , Imunossupressores/farmacologia , Chumbo/farmacocinética , Nigella sativa , Animais , Relação Dose-Resposta a Droga , Feminino , Sistema Imunitário/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Especificidade de Órgãos/efeitos dos fármacos
8.
Anal Sci ; 22(12): 1611-4, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17159326

RESUMO

A simple and sensitive indirect spectrophotometric method for the assay of meloxicam (MX), tenoxicam (TX) and piroxicam (PX) in pure and in pharmaceutical formulations by flow injection analysis (FIA) has been proposed. The method is based on the oxidation of these drugs by a known excess of N-bromosuccinimide (NBS) in an acidic medium, followed by a reaction of excess oxidant with chloranilic acid (CAA) to bleach its purple color. The absorbance values increased linearly with increasing concentrations of the drugs. Variables, such as the acidity, reagent concentrations, flow rate of reagents and other FI parameters were optimized to produce the most sensitive and reproducible results. The system obeyed Beer's low over concentration ranges of 10 - 160, 20 - 200 and 10 - 160 microg/ml for MX, TX and PX, respectively. The common excipients and additives did not interfere with their determinations. The method was successfully applied to the determinations of MX, TX and PX in various pharmaceutical preparations. The results obtained by the proposed method were found to be in good agreement with those found by the official HPLC methods.


Assuntos
Preparações Farmacêuticas/análise , Análise Espectral/métodos , Tiazinas/análise , Benzoquinonas , Bromosuccinimida , Meloxicam , Oxirredução , Piroxicam/análogos & derivados , Piroxicam/análise , Tiazóis/análise
9.
Anaesthesia ; 59(3): 283-9, 2004 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-14984528

RESUMO

Angioedema of the face and neck is an uncommon but potentially life-threatening complication of angiotensin-converting enzyme (ACE) inhibitor therapy. This condition is of particular concern to the anaesthetist as it can rapidly progress to upper airway obstruction. We describe the presentation and management of five cases of ACE inhibitor related angioedema, all of which were associated with significant upper airway obstruction.


Assuntos
Obstrução das Vias Respiratórias/induzido quimicamente , Angioedema/induzido quimicamente , Inibidores da Enzima Conversora de Angiotensina/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Obstrução das Vias Respiratórias/terapia , Anestesia/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
10.
J Environ Monit ; 4(6): 985-9, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12509055

RESUMO

Al, Cd, Cr, Cu, Fe, Mn, Pb, Zn, NH4+, Mg2+, Ca2+, Na+, K+, Cl-, NO3- and SO4(2-), along with pH were determined in wet and dry deposition samples collected at Al-Hashimya, Jordan. Mean trace metal concentrations were similar or less than those reported for other urban regions worldwide, while concentrations of Ca2+ and SO4(2-) were the highest. The high Ca2+ concentrations were attributed to the calcareous nature of the local soil and to the influence of the Saharan dust, while the high concentrations of SO4(2-) were attributed to the influence of anthropogenic sources and Saharan dust soil. Except for SO4(2-), NO3-, and Ca2+, dry deposition fluxes of measured metals and ions were higher than their corresponding wet deposition fluxes. The high annual average pH values recorded for wet and dry deposition samples were attributed to the neutralization of acidity by alkaline species. Cd, Cr, Cu, Pb, Zn, NO3- and SO4(2-) were enriched in wet and dry deposition samples relative to crustal material, and a significant anthropogenic contribution to these elements and ions is tentatively suggested. Finally, the possible sources and the main factors affecting the concentrations of the measured species are discussed.


Assuntos
Poluentes Atmosféricos/análise , Metais Pesados/análise , Oligoelementos/análise , Poeira , Monitoramento Ambiental , Concentração de Íons de Hidrogênio , Indústrias , Jordânia , Chuva
11.
J Environ Monit ; 4(6): 990-6, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12509056

RESUMO

The levels of lead, cadmium, copper, zinc, aluminum, chromium, and iron in street dust, soil, and plants in the Jordanian petroleum refinery were determined using flame and graphite-furnace atomic absorption spectrophotometry. Major cations (Li+, Na+, NH4+, K+, Mg2+, and Ca2+) and anions (F-, Cl-, NO3-, SO4(2-), and Br-) were also determined using suppression mode ion chromatography. Generally, higher levels of the heavy metals studied were found in street dust samples than in soil samples. On the other hand, except Cl-, and Li+ ions, other anions and cations showed higher concentrations in soil than in street dust samples. For plant samples, unwashed samples showed higher levels of heavy metals than their washed counterparts, indicating that dust fall is a source of heavy metal contamination.


Assuntos
Poluentes Ambientais/análise , Metais Pesados/análise , Petróleo , Poluentes do Solo/análise , Cidades , Poeira , Indústrias , Jordânia , Plantas , Solubilidade , Espectrofotometria Atômica
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