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PubMed1999

Aluminum-induced oxidative events in cell lines: glioma are more responsive than neuroblastoma.

Aluminum, a trivalent cation unable to undergo redox reactions, has been linked to many diseases such as dialysis dementia and microcytic anemia without iron deficiency. It has also been implicated in Alzheimer's disease although this is controversial. Because cell death due to oxidative injury is suspected to be a contributory factor in many neurological diseases and aluminum neurotoxicity, glioma (C-6) and neuroblastoma (NBP2) cells were utilized to assess early changes in oxidative parameters consequent to a 48-h exposure to aluminum sulfate. A 500-microM concentration of this salt produced a significant increase in reactive oxygen species (ROS) production and a significant decrease in glutathione (GSH) content in glioma cells. However, the same concentration of the aluminum salt did not lead to any significant changes in the neuroblastoma cells. Mitochondrial respiratory activity in glioma cells was also found to be significantly higher in the aluminum treated cells. As judged by morin-metal complex formation, aluminum can enter glioma cells much more readily than neuroblastoma cells. Thus, it is possible that the cerebral target following an acute exposure to aluminum may be glial rather than neuronal.

Alum Compounds↗
PubMed2001

Effect of aluminum sulfate and cationic polyelectrolytes on the destabilization of emulsified wastes.

Emulsified oil in wastewater constitutes a severe problem in the different treatment stages. Aluminum salts have been traditionally used as coagulants in wastewater treatments. Polyelectrolytes are used to coagulate and flocculate colloidal systems. The performance of aluminum sulfate in comparison to polyelectrolytes (chitosan and polyacrylamide) as conditioning chemicals for an emulsion waste was tested, and the predominant mechanisms acting in each case were analyzed. Turbidimetry, jar test, colloidal titration and microscopy were used to test emulsion destabilization. Both charge neutralization and bridge formation were identified and confirmed as mechanisms of interaction of polyelectrolytes with waste constitutents. Charge neutralization would be more important for chitosan than for polyacrylamide treatment. A coincidence between the doses necessary to reach zero colloidal charge and minimum turbidity was observed for polyelectrolytes. The time necessary to produce system clarification was larger for aluminum sulfate than for polyelectrolytes; this time was shortened for higher aluminum sulfate concentration. The pH showed a marked effect on aluminum sulfate performance with the optimum at pH 6; polyelectrolyte action was practically not affected by pH. Polyelectrolyte addition produced the minimum turbidity for the same doses that zero colloidal charge; at higher doses, emulsion was restabilized and became turbid again. However, aluminum sulfate treatment did not produce emulsion restabilization.

Acrylic Resins↗
PubMed2002

Integrated effects of applied pressure, time, and polymer doses on alum sludge dewatering behaviour.

In this study, combinations of applied pressure, pressing time and polymer dose were examined in an air pressure plate apparatus to explore their integrated influence on the dewatering of an alum sludge. Results of the investigation demonstrated that dewatering can be enhanced by increases in pressure and time. However, a point is reached at which continued increases in pressure and time offer little benefit. The data also confirmed that polymer affects the rate of water release rather than the extent of dewatering. Increased rates of water release due to increasing polymer dose can be attributed to the aggregation of sludge particles by polymer addition. It was also evident in this study that the initial sludge depth has a major impact on the average cake moisture content at a given dewatering time. It was apparent that once the initial sludge thickness exceeds about 2 cm, the water release follows a fairly similar pattern, which can be represented by a simple empirical model.

Alum Compounds↗
PubMed1998

A simple and rapid stain for copper in liver tissue.

We report a modified copper stain that can be completed in 2 hours, rather than overnight, which is required for other stains. This is useful in the diagnosis of chronic cholestatic syndromes, Wilson's disease, Indian childhood cirrhosis, and other conditions associated with copper retention.

Alum Compounds↗
PubMed2000

Infrared and polarized Raman spectra of (CH3)2NH2Al(SO4)2 x 6H2O.

FTIR and single crystal Raman spectra of (CH3)2NH2Al(SO4)2 x 6H2O have been recorded at 300 and 90 K and analysed. The shifting of nu1 mode to higher wavenumber and its appearance in Bg species contributing to the alpha(xz) and alpha(yz) polarizability tensor components indicate the distortion of SO4 tetrahedra. The presence of nu1 and nu2 modes in the IR spectrum and the lifting of degeneracies of nu2, nu3, and nu4 modes are attributed to the lowering of the symmetry of the SO4(2-) ion. Coincidence of the IR and Raman bands for different modes suggest that DMA+ ion is orientationally disordered. One of the H atoms of the NH2 group of the DMA+ ion forms moderate hydrogen bonds with the SO4(2-) anion. Al(H2O)6(3+) ion is also distorted in the crystal. The shifting of the stretching modes to lower wavenumbers and the bending mode to higher wavenumber suggest that H2O molecules form strong hydrogen bonds with SO4(2-) anion. The intensity enhancement and the narrowing of nu1SO4, deltaC2N and Al(H2O)6(3+) modes at 90 K confirm the settling down of the protons in the hydrogen bonds formed with H2O molecules and NH2 groups. This may be one of the reasons for the phase transition observed in the crystal.

Alum Compounds↗
PubMed2000

Application of aluminium(III) complex with salicylidene-o-aminophenol to the fluorometric determination of nucleic acids.

In buffer medium of hexamethylene tetraamine-HCl at pH 5.9 the aluminium(III) complex with salicylidene-o-aminophenol (SAP) has a fluorescence peak at 508 nm with excitation at 410 nm. When nucleic acid coexists, it reacts with the complex within 8 min at room temperature to produce a non-fluorescent product, resulting in the decrease of fluorescence intensity of the aluminium complex. On basis of this, a new fluorometric method for nucleic acids determination is proposed. The calibration graphs for calf thymus DNA, fish sperm DNA and yeast RNA are linear up to 5.0, 4.0 and 3.0 microg ml(-1), respectively, and corresponding detection limits are 49, 52 and 62 ng ml(-1). The synthetic samples are analyzed with relative standard deviation of five measurements of 3.9-6.0%. DNA in an extraction product from human blood is determined using the calibration graph for calf thymus DNA, and the result is very close to that by the ethidium bromide assay. Compared with some established fluorometric methods, this procedure is sensitive, selective, reliable, reproducible and practical. The association constant of calf thymus DNA with the complex is estimated by two graphic methods. It is suggested that the binding reaction between nucleic acids with the complex proceeds in an intercalation way.

Alum Compounds↗
PubMed2001

HIV epitope-peptides in aluminum adjuvant induced high levels of epitope-specific antibodies.

Some neutralizing epitopes on HIV-1 envelope proteins were shown to induce antibodies that could effectively inhibit the infection of different HIV-1 strains in vitro. But only very low levels of antibodies to these epitopes were determined in the HIV-1 infected individuals. In this study, the aluminum (alum) adjuvant to increase the immunogenicity of the neutralizing epitopes was used. Three epitope-peptides [C-(ELDKWAG)4, C-(RILAVERYLKD-G)2 and C-(GPGRAFY)2], which contain three epitopes (ELDKWA, RILAVERYLKD, GPGRAFY) from the HIV-1 Env proteins, were synthesized and conjugated to carrier protein keyhole limpet hemocyanin (KLH). The epitope-vaccines C-(ELDKWAG)4-KLH and C-(RILAVERYLKD-G)2-KLH in alum induced high levels of epitope-specific antibodies recognizing the epitopes from epitope-peptides C-(ELDKWAG)4 and C-(RILAVERYLKD-G)2, as well as the gp41 C-domain peptides P2 [C-TSLIHSLIEESQNQQEKNEQELLELDKWA (aa 646-674)] and P1 [LQARILAVERYLKDQQL (aa 583-599)] and the recombinant soluble gp41 (rsgp41) bearing both epitopes (antibody titer in rabbit sera was 1:12800-25,600 dilution). Immunoblotting analysis demonstrated that the antibodies in both antisera bound to rsgp41, indicating that both antibodies recognized the natural epitopes on rsgp41 protein. The epitope-vaccines C-(GPGRAFY)2-KLH induced moderate GPGRAFY epitope-specific antibody response with a titer of 1:6,400. In contrast, as it was demonstrated in previous studies, the immunization with rgp160 induced weak antibody response to these three epitopes (titer of 1:400-1600). This suggests that epitope-peptides conjugated to KLH when infected with alum significantly increases immunogenicity of gp41 neutralizing epitopes providing a hope for the development of an HIV-1 vaccine.

AIDS Vaccines↗
PubMed2000

Imparting biomimetic ion-gating recognition properties to electrodes with a hydrogen-bonding structured core-shell nanoparticle network.

This paper presents findings of the creation of biomimetic ion-gating properties with core-shell nanoparticle network architectures. The architectures were formed by hydrogen-bonding linkages via an exchange-cross-linking-precipitation reaction pathway using gold nanoparticles capped with thiolate shell and alkylthiols terminated with carboxylic groups as model building blocks. Such network assemblies have open frameworks in which void space is in the form of a channel or chamber with the nanometer-sized cores defining its size, the geometric arrangement defining its shape, and the shell structures defining its chemical specificity. The formation of the network linkages via head-to-head hydrogen-bonded carboxylic terminals and the reversible pH-tuned structural properties between neutral and ionic states were characterized using infrared reflectance spectroscopic technique. The biomimetic ion-gating properties were demonstrated by measuring the pH-tuned network "open-close" responses to charged redox probes. Such redox responses were shown to depend on the degree of protonation-deprotonation of carboxylic groups at the interparticle linkages, core sizes of the nanoparticles, and charges of the redox probes. Differences in structural networking, pH-tuning, and electrochemical gating properties were identified between the network films derived from nanoparticles of two different core sizes (2 and 5 nm). The mechanistic correlation of these structural properties was discussed. These findings have added a new pathway to the current approaches to biomimetic molecular recognition via design of core-shell nanoparticle architectures at both nanocrystal and molecular scales.

Alum Compounds↗
PubMed2002

Formation quotients of aluminum sulfate complexes in NaCF3SO3 media at 10, 25, and 50 degrees C from potentiometric titrations using a mercury/mercurous sulfate electrode concentration cell.

Mercury/mercurous sulfate electrode concentration cells (with liquid junction) are employed in this study to determine the formation constants of aluminum sulfate complexes, with the principal advantage that the change in the free sulfate concentration is measured directly without the need to know the standard potential of the electrode. Potentiometric titrations were conducted at temperatures of 10, 25, and 50 degrees C and ionic strengths of approximately 0.3, 0.5, and 1.0 molal in aqueous solutions of the inert 1:1 electrolyte sodium trifluoromethanesulfonate (NaTr). Stoichiometric molal formation quotients Q1 and Q2, respectively, for the reactions Al3+(aq) + SO4(2-)(aq) AlSO4+(aq) and Al3+(aq) + 2SO4(2-)(aq) <= >Al(SO4)2-(aq) were determined. The values of log Q1 obtained from this work in NaTr media at ionic strengths of 0.3 and 1.0 mol x kg(-1) and 50 degrees C (1.72 +/- 0.08 and 1.35 +/- 0.06, respectively) are in excellent agreement with the values (1.71 +/- 0.2 and 1.32 +/- 0.1) determined in NaCl media from the recent potentiometric study conducted in the same laboratory using a hydrogen electrode concentration cell by Ridley et al. (Ridley, M. K.; Wesolowski, D. J.; Palmer, D. A.; Kettler, R. M. Geochim. Cosmochim. Acta 1999, 62, 459-472). The value of log Q2 (2.05 +/- 0.05) in 1.0 mol x kg(-1) from this work is smaller than the value reported by Ridley et al. (2.6 +/- 0.5) but within the combined experimental error. Empirical isothermal equations are presented to permit calculation of the equilibrium quotients as a function of ionic strength (0-1 mol x kg(-1)), giving log K1 and log K2 values at 25 degrees C and infinite dilution of 3.84 +/- 0.12 and 5.58 + 0.09, respectively. The value for log K1 obtained in this study at 25 degrees C is bracketed within experimental uncertainty by values reported by Kryzhanovskii et al. (Kryzhanovskii, M. M.; Volokhov, Y. A.; Pavlov, L. N.; Eremin, N. I.; Mironov, V. E Zh. Prikl. Khim. 1971, 44,476-479) and Nishide and Tsuchiya (Nishide, T.; Tsuchiya, R. Bull. Chem. Soc. Jpn. 1965, 38, 1398-1400), namely, 3.89 and 3.73, respectively. All other literature values for the first aluminum sulfate association constant are considerably lower than these results, which is also true for the second association constant, although there are few experimental data available for the latter. Empirical equations are also presented for calculating values of log Q1 and log Q2 from 0 to 1 molal ionic strength and from 10 to 125 degrees C, spanning the range of most environmental conditions at which these reactions are important.

Alum Compounds↗
PubMed2002

Livestock ammonia management and particulate-related health benefits.

Agricultural operations are the largest source of ammonia emissions in the United States and contribute to the formation of ammonium nitrate and ammonium sulfate, two prevalent forms of fine particulate matter. Researchers have found an association between fine particulate matter and a variety of adverse healths effects, including premature mortality, chronic bronchitis, hospital admissions, and asthma attacks. Management practices that reduce ammonia emissions may decrease adverse health effects, resulting in significant economic benefits. We estimated the impact of a variety of emission controls, including diet optimization, alum, and incorporation of manure into the land. The results suggest that relatively modest management policies can have a significant impact on fine particulate formation in the atmosphere. Because of the heterogeneous nature of particulate matter, a key question is the importance of particulate matter size and composition. To the extent that ammonium nitrate and ammonium sulfate contribute to adverse health effects, ammonia management may have significant health implications. Our results suggestthat a 10% reduction in livestock ammonia emissions can lead to over $4 billion annually in particulate-related health benefits.

Agriculture↗
PubMed2002

Solid-state speciation of natural and alum-amended poultry litter using XANES spectroscopy.

While alum amendments have shown to be effective in lowering water-soluble phosphate levels in poultry litter, the mechanism by which this occurs is not fully known. To determine the solid-state speciation of phosphate in litter samples, experiments were conducted with X-ray absorption near edge structure (XANES) spectroscopy. XANES analysis reveals that, in unamended samples, phosphate is present as weakly bound inorganic as well as some organic phosphate, with some dicalcium phosphate-type calcium phosphates also present. When alum is applied in the houses, XANES results suggest that it precipitates out as amorphous Al(OH)3 and then reacts with phosphate via an adsorption mechanism. No evidence was found of aluminum phosphate precipitation in any samples.

Alum Compounds↗
PubMed2003

Selective coagulant recovery from water treatment plant residuals using Donnan membrane process.

Fouling of membrane surfaces by particulate matter and large organic molecules is relatively common for pressure-driven membrane processes, namely, reverse osmosis (RO), nanofiltration (NF), and ultrafiltration (UF). Donnan membrane process (DMP) or Donnan Dialysis is driven by electrochemical potential gradient across a semipermeable ion exchange membrane. Theoretically, DMP is not susceptible to fouling by fine particulates and/or large organic molecules. According to information available in the open literature, however, DMP has not been tried to treat slurry or sludge with relatively high concentration of suspended solids or large organic molecules. This study presents the salient results of an extensive investigation pertaining to selective alum recovery from water treatment residuals (WTR) using DMP. Water treatment plants use alum, Al2(SO4)3 x 14H2O, as a coagulant, alum being finally converted and discharged as insoluble aluminum hydroxide along with natural organic matters (NOM), suspended solids, and other trace impurities. One commercial cation exchange membrane, namely Nafion 117 from DuPont Chemical Co., was used in the study for treating WTR obtained from two different water treatment plants in Pennsylvania. A series of laboratory tests confirmed that over 70% of alum is easily recoverable, and recovered alum is essentially free of particulate matter, NOM, and other trace metals. Most importantly, after repeated usage in the presence of high concentration of NOM and suspended solids, there was no noticeable decline in aluminum flux through the membrane, i.e., membrane surface fouling was practically absent. The DMP process involves coupled transport of Al3+ and H+ across the cation exchange membrane, and intramembrane transport was the rate-limiting step. Experimentally determined aluminum-hydrogen interdiffusion coefficient (D(Al-H)) values within the membrane were quite high (approximately 10(-6) cm2/s) under representative conditions, thus confirming high alum recovery rate. DMP was also found equally effective in recovering Fe(III) based coagulants from WTR.

Alum Compounds↗
PubMed2003

Virus inactivation in aluminum and polyaluminum coagulation.

Inorganic aluminum salts, such as aluminum sulfate, are coagulants that cause small particles, such as bacteria and viruses as well as inorganic particles, to destabilize and combine into larger aggregates. In this investigation, batch coagulation treatments of water samples spiked with Qbeta, MS2, T4, and P1 viruses were conducted with four different aluminum coagulants. The total infectious virus concentration in the suspension of floc particles that eventually formed by dosing with coagulant was measured after the floc particles were dissolved by raising the pH with an alkaline beef extract solution. The virus concentrations were extremely reduced after the water samples were dosed with aluminum coagulants. Viruses mixed with and adsorbed onto preformed aluminum hydroxide floc were, however, completely recovered after the floc dissolution. These results indicated that the aluminum coagulation process inactivates viruses. Virucidal activity was most prominent with the prehydrolyzed aluminum salt coagulant, polyaluminum chloride (PACl). Virucidal activity was lower in river water than in ultrapure water--natural organic matter in the river water depressed the virucidal activity. Mechanisms and kinetics of the virus inactivation were discussed. Our results suggest that intermediate polymers formed during hydrolysis of the aluminum coagulants sorbed strongly to viruses, either rendering them inactive or preventing infectivity.

Adsorption↗
PubMed2004

Direct speciation of phosphorus in alum-amended poultry litter: solid-state 31P NMR investigation.

Amending poultry litter (PL) with aluminum sulfate (alum) has proven to be effective in reducing water-soluble phosphorus (P) in the litter and in runoff from fields that have received PL applications; it has therefore been suggested as a best management practice. Although its effectiveness has been demonstrated on a macroscopic scale in the field, little is known about P speciation in either alum-amended or unamended litter. This knowledge is important forthe evaluation of the long-term stability and bioavailability of P, which is a necessary prerequisite forthe assessment of the sustainability of intensive poultry operations. Both solid-state MAS and CP-MAS 31P NMR as well as 31P[27Al]-TRAPDOR were used to investigate P speciation in alum-amended and unamended PL. The results indicate the presence of a complex mixture of organic and inorganic orthophosphate phases. A calcium phosphate phase, probably a surface precipitate on calcium carbonate, could be identified in both unamended and alum-amended PL, as well as physically bound HPO4(2-). Phosphate associated with Al was found in the alum-amended PL, most probably a mixture of a poorly ordered wavellite and phosphate surface complexes on aluminum hydroxide that had been formed by the hydrolysis of alum. However, a complex mixture of organic and inorganic phosphate species could not be resolved. Phosphate associated with Al comprised on average 40 +/- 14% of the total P in alum-amended PL, whereas calcium phosphate phases comprised on average 7 +/- 4% in the alum-amended PL and 14 +/- 5% in the unamended PL.

Alum Compounds↗
PubMed2005

Breakage, regrowth, and fractal nature of natural organic matter flocs.

The growth, breakage, regrowth, and fractal nature of flocs was investigated by use of a laser diffraction particle sizing device. A range of coagulants were investigated for the coagulation of natural organic matter (NOM) and compared to other coagulated systems. The results showed NOM floc structural characteristics varied in steady-state size depending upon which coagulant was used. When compared to other systems, the order of floc size was Fe precipitate > Fe-NOM > latex (in NaCl solution). Floc regrowth after exposure to high shear was limited for all of the flocs under investigation other than for latex in an inert electrolyte. This highlighted differences in the internal bonding structure of flocs, with the results suggesting that physical bonds have a capacity to re-form after breakage. Fractal dimension analysis by small-angle laser light scattering (SALLS) had limited applicability to large flocs that dominated all of the systems under investigation, but the degree of compaction increased as flocs were broken in high shear. This provided a possible mechanistic reason for the irreversible breakage seen.

Alum Compounds↗
PubMed2005

Relative risk analysis of several manufactured nanomaterials: an insurance industry context.

A relative risk assessment is presented for the industrial fabrication of several nanomaterials. The production processes for five nanomaterials were selected for this analysis, based on their current or near-term potential for large-scale production and commercialization: single-walled carbon nanotubes, bucky balls (C60), one variety of quantum dots, alumoxane nanoparticles, and nano-titanium dioxide. The assessment focused on the activities surrounding the fabrication of nanomaterials, exclusive of any impacts or risks with the nanomaterials themselves. A representative synthesis method was selected for each nanomaterial based on its potential for scaleup. A list of input materials, output materials, and waste streams for each step of fabrication was developed and entered into a database that included key process characteristics such as temperature and pressure. The physical-chemical properties and quantities of the inventoried materials were used to assess relative risk based on factors such as volatility, carcinogenicity, flammability, toxicity, and persistence. These factors were first used to qualitatively rank risk, then combined using an actuarial protocol developed by the insurance industry for the purpose of calculating insurance premiums for chemical manufacturers. This protocol ranks three categories of risk relative to a 100 point scale (where 100 represents maximum risk): incident risk, normal operations risk, and latent contamination risk. Results from this analysis determined that relative environmental risk from manufacturing each of these five materials was comparatively low in relation to other common industrial manufacturing processes.

Alum Compounds↗
PubMed1998

Effects of aluminum sulphate and citric acid ingestion on lipid peroxidation and on activities of superoxide dismutase and catalase in cerebral hemisphere and liver of developing young chicks.

Effect of oral administration of aluminum sulphate (200 and 400 mg/kg body wt/day) without or with citric acid (62 mg/kg body wt/day) to day-old White Leghorn male chicks (n = 5 per group) for 30 days was studied on the activities of superoxide dismutase (SOD) and catalase, and level of lipid peroxidation in cerebral hemisphere and liver. A 400 mg dose of Al in the presence of citric acid inhibited cytosolic total and CN -sensitive superoxide dismutase activities of the cerebral hemisphere in 7- and 30-day treated chicks, whereas in 15-day treated chicks the enzyme activities were decreased in response to both doses in the presence of citric acid. In case of liver, activities of these enzymes significantly decreased after 7, 15 and 30 days of treatment with 200 and 400 mg Al together with citric acid, whereas 400 mg Al alone inhibited the enzyme activities after 15 and 30 days of treatment. Cerebral catalase activity decreased in response to 400 mg Al when the chicks were also fed with citric acid for 7 and 30 days, but in 15-day treated chicks the enzyme activity was depleted following treatment with 200 and 400 mg Al combined with citric acid. 400 mg Al treatment for 7 days in combination with citric acid inhibited hepatic catalase activity and extension of the treatment period to 15 and 30 days also produced reduction in its activity even in response to the lower Al dose mixed with citric acid. CN -insensitive SOD activity of cerebral hemisphere and liver was unaffected by Al. Al also failed to induce lipid peroxidation in both the tissues throughout the course of exposure. Activities of SOD and catalase of cerebral hemisphere and liver of 30-day old chicks were observed to be inhibited by in vitro incubation with different concentrations of Al. Our in vivo study demonstrates that only CN -sensitive SOD is susceptible to Al. Further, responses of SOD and catalase to Al is tissue specific. The observed inhibition of antioxidant enzyme activities by Al is suggestive of a prooxidant state. Induction of such an oxidative condition of the tissues may be attributed to a direct effect of the metal on enzyme molecules or in their synthesis.

Alum Compounds↗