Interference of Parenteral Nutrition Components in Silicon-Mediated Protection Against Aluminum Bioaccumulation.

Aluminum and silicon are contaminants found in formulations used to prepare parenteral nutrition. Both elements are leached from glass containers, mainly during the heating cycle for sterilization. Insoluble and biologically inactive species of hydroxyaluminosilicates have been shown to form in solutions containing Al and Si.

Simultaneous determination of iron and nickel as contaminants in multimineral and multivitamin supplements by solid sampling HR-CS GF AAS.

A methodology to assay simultaneously iron and nickel present as contaminants in multimineral and multivitamin supplements was investigated. High-resolution continuum source graphite furnace atomic absorption spectrometry and direct solid sample analysis were used. Measurements were done with the secondary lines of Fe (352.

Extraction/Leaching of Metal-Containing Additives from Polyvinyl Chloride, Ethyl Vinyl Acetate, and Polypropylene Bags and Infusion Sets into Infusion Solutions.

Flexible medical devices are primarily made of plasticized polyvinyl chloride (PVC). In recent times, to avoid undesired migration of the PVC plasticizers, ethyl vinyl acetate (EVA) and polypropylene (PP) has replaced PVC. Nevertheless, other additives are necessary to generate useful polymeric materials.

Determination of Antimony in Pharmaceutical Formulations and Beverages Using High-Resolution Continuum-Source Graphite Furnace Atomic Absorption Spectrometry.

A sensitive and accurate method, employing high-resolution continuum source atomic absorption spectrometry, for the determination of antimony (Sb) was developed. Conditions such as pyrolysis and atomization temperatures, the use of chemical modifiers, and sample pretreatment were optimized for the determination of Sb in pharmaceutical preparations and beverages stored in polyethylene terephthalate (PET) containers. In addition to container analysis, the influence of time of contact, temperature, and content composition on the migration of Sb was investigated.

Determination of chlorine via the CaCl molecule by high-resolution continuum source graphite furnace molecular absorption spectrometry and direct solid sample analysis.

This work investigates the possibilities of high-resolution continuum source graphite furnace molecular absorption spectrometry for the direct determination of Cl in solid samples via the CaCl molecule and measurement of its molecular absorption. The method proposed is based on addition of 400µg Ca as molecule-forming reagent and of 20µgPd as chemical modifier, which helps to stabilize the analyte and enhances sensitivity. The molecular spectrum for CaCl offers different lines with different limits of detection and linear ranges, which permitted to analyze solid samples with different Cl contents.

Salting-out assisted liquid-liquid extraction and partial least squares regression to assay low molecular weight polycyclic aromatic hydrocarbons leached from soils and sediments.

A novel method was developed to determine low molecular weight polycyclic aromatic hydrocarbons in aqueous leachates from soils and sediments using a salting-out assisted liquid-liquid extraction, synchronous fluorescence spectrometry and a multivariate calibration technique. Several experimental parameters were controlled and the optimum conditions were: sodium carbonate as the salting-out agent at concentration of 2molL, 3mL of acetonitrile as extraction solvent, 6mL of aqueous leachate, vortexing for 5min and centrifuging at 4000rpm for 5min. The partial least squares calibration was optimized to the lowest values of root mean squared error and five latent variables were chosen for each of the targeted compounds.

Applications of computational chemistry to the study of the antiradical activity of carotenoids: A review.

A summary of the various quantum chemical analyses that have been employed to evaluate the free radical scavenger capacity of carotenoid molecules are tabulated in this review and the most important observations are discussed. These molecules are able to interact with reactive oxygen species through singlet oxygen scavenging, electron transfer, hydrogen atom abstraction and radical adduct formation. Most studies employ density functional theory to compare the antiradical capacity of different carotenoids with the ones that are most explored theoretically, such as lycopene and β-carotene.

A liquid chromatography-atmospheric pressure photoionization tandem mass spectrometric method for the determination of organosulfur compounds in petroleum asphalt cements.

We present a sensitive liquid chromatography-atmospheric pressure photoionization tandem mass spectrometric (UHPLC-APPI-MS/MS) method for the determination of selected organosulfur compounds in Brazilian asphalt cements. It was possible to detect 14 organosulfur compounds of different classes where sulfoxides and sulfones presented higher sensibility in ionization than thiophenes and aromatic sulfides. A dopant-assisted APPI method was also tested, however, when chromatographic flow rate was optimized a decrease in signal was observed for all compounds.

Simultaneous determination of cobalt and nickel in vitamin B12 samples using high-resolution continuum source atomic absorption spectrometry.

Nickel and cobalt were simultaneously assayed in vitamin B12 formulations by using atomic spectrometry. The proposed method is based on a compromise between the proximity of specific Ni and Co spectral lines and the relative abundances of the analytes in the samples. The analytes were found in concentrations ranging from 9.

Ultrasound-Assisted Extraction and Biological Activities of Extracts of var. .

In this work, the antioxidant and antimicrobial activities of var. extracts obtained through ultrasound-assisted extraction are evaluated. The extracts obtained using the best extraction conditions were subjected to different hydrolysis conditions before their use in the biological tests.

The effect of prior exercise intensity on oxygen uptake kinetics during high-intensity running exercise in trained subjects.

Purpose: The aim of this study was to compare the effects of two different kinds of prior exercise protocols [continuous exercise (CE) versus intermittent repeated sprint (IRS)] on oxygen uptake (VO2) kinetics parameters during high-intensity running.

Methods: Thirteen male amateur futsal players (age 22.8 ± 6.

Supercritical CO2 extraction, chemical characterisation and antioxidant potential of Brassica oleracea var capitata against HO·, O2(·-) and ROO·.

In this work were extracted bioactive compounds from Brassica oleracea var capitata using supercritical CO2 and evaluated the antioxidant potential of the extracts. Five extractions were accomplished to investigate the influence of pressure (10-25 MPa) and temperature (20-60 °C) in the extraction yield, chemical composition and antioxidant potential towards peroxyl, superoxide and hydroxyl radicals. The highest extraction yield was obtained at 60 °C and 25 MPa, which was 0.

Accumulation, elimination, and effects of parenteral exposure to aluminum in newborn and adult rats.

Aluminum (Al) delivered to preterm infants via parenteral nutrition may exceed the limit of 5 μg/kg/day set by the US Food and Drug Administration. This study evaluated the effect of the administration of an equivalent amount of Al (0.12 mg/kg/day) to newborn rats.

Aluminum in erythropoietin formulations: lyophilized versus liquid forms.

Background: Erythropoietin (EPO) formulations may comprise aluminum (Al) as a contaminant. Due to the toxicity of Al in chronic kidney disease patients, possible sources of Al were investigated. Since EPO formulations are stored in container-closure systems made of glass and rubber, and both contain Al, formulation ingredients may enable its leaching into the solution during shelf-life.

Evidence for aluminum-binding erythropoietin by size-exclusion chromatography coupled to electrothermal absorption atomic spectrometry.

Erythropoietin (EPO) is a glycoprotein that stimulates erythropoiesis and is clinically used for treating anemia during chronic renal failure and for anemia in preterm infants. EPO formulations usually have elevated rates of contamination due to aluminum (Al), which is toxic to both types of patients. Size-exclusion chromatography (SEC) coupled with graphite furnace atomic absorption spectrometry (GF AAS) was employed to separate proteins and to quantify the amount of aluminum present in the elution volume corresponding to EPO and, therefore, to evaluate possible binding.

Presence of synthetic pharmaceuticals as adulterants in slimming phytotherapeutic formulations and their analytical determination.

Obesity that is associated with a high consumption of slimming substances is considered a public health problem around the world. In this context, the increasing consumption of phytotherapeutic formulations as alternative obesity treatments has revealed the presence of synthetic pharmaceuticals as adulterants. The illegally added adulterants are frequently anorexic, anxiolytic, and antidepressant pharmaceuticals.

Chromatography and atomic absorption spectrometry for the assessment of heavy metal distribution among amino acids used in parenteral nutrition formulations-studies with cadmium and lead.

The distribution of Cd (II) and Pb (II) among amino acids in parenteral nutrition formulations was investigated by coupling ion-chromatography (HPLC/IC) and electrothermal atomic absorption spectrometry. The methodology was based on ion-exchange separation and fluorimetric amino acid detection after post-column derivatization. Cd (II) and Pb (II) were assayed in 500-µL fractions of the column effluent.

A new method for the simultaneous determination of 1,4-benzodiazepines and amfepramone as adulterants in phytotherapeutic formulations by voltammetry.

The use of synthetic pharmaceuticals in phytotherapeutics can be defined as an illegal practice, since these compounds are normally present as non-declared compounds in the phytotherapeutical formulations. This work aims to show the development of an analytical method based on adsorptive cathodic stripping voltammetry (AdCSV) for the simultaneous determination of 1,4-benzodiazepines and amfepramone. The developed method was used to measure seven benzodiazepines (clonazepam, flurazepam, alprazolam, midazolam, medazepam, chlordiazepoxide, and diazepam) and amfepramone in slimming formulations that have been commercialized in Brazil.

Aluminum content in intravenous solutions for administration to neonates: role of product preparation and administration methods.

Background: Aluminum loading can reach toxic levels depending on the amount of aluminum intake in intravenous solutions (IV). Premature infants are at a higher risk of aluminum toxicity because of their reduced urinary aluminum elimination. All steps involved in the preparation of intravenous solutions for premature neonates in intensive care units were evaluated to determine to what degree, if any, they increased the aluminum load and should be considered when assessing the daily aluminum intake (<5 mcg/kg) established by the U.

Voltammetric determination of Se(IV) and Se(VI) in saline samples--studies with seawater, hydrothermal and hemodialysis fluids.

Determination of Se(IV) and Se(VI) in high saline media was investigated by cathodic stripping voltammetry (CSV). The voltammetric method was applied to assay selenium in seawater, hydrothermal and hemodialysis fluids. The influence of ionic strength on selenium determination is discussed.

Low availability of aluminum in formulations for parenteral nutrition containing silicate.

Background: Silicate (Si) and aluminum (Al) may be concomitant impurities in solutions for parenteral nutrition (PN). Silicate can bind to Al to form stable hydroxyaluminosilicates (HAS), thus reducing Al availability. This possibility is investigated by heating solutions containing constituents of PN in glass containers to promote the release of Si and Al.

Performance of polymeric materials for solid phase extraction prior to chromatographic analysis.

Synthetic polymeric materials such as polyethylene and polyurethane (PU) were compared to conventional adsorbents for solid phase extraction for cleaning up biological samples. Efficiency in eliminating proteins and other components usually present in biological samples, such as serum, urine, and tissues extracts, was evaluated. The assays consisted of measuring the remaining protein content in serum and tissue homogenates (liver) and collecting the spectra in the UV region for urine samples.

Role of medication in the level of aluminium in the blood of chronic haemodialysis patients.

Background: Although dialysis facilities provide high-quality water, abnormal aluminium levels among patients on haemodialysis have still been reported. Since patients with chronic kidney disease are often on multiple medications, medicines may be an extra source of aluminium for them. The degree to which ingesting contaminated medication influenced the level of aluminium in the patients' blood was investigated.

Determination of cadmium, lead and thallium in highly saline hemodialysis solutions by potentiometric stripping analysis (PSA).

Potentiometric stripping analysis (PSA) was investigated to assay simultaneously cadmium, lead and thallium present as contaminants in highly saline solutions used in hemodialysis. The saline matrices were sodium, potassium, magnesium and calcium chlorides, sodium acetate, sodium bicarbonate and glucose, which constitute concentrates for hemodialysis. A 1000mugmL(-1) Hg(II) solution was used to prepare the mercury film electrode (MFE) and to carry out the stripping step.

HPLC based method using sample precolumn cleanup for the determination of triazines and thiolcarbamates in hemodialysis saline solutions.

Solid-phase extraction (SPE) procedures for cleanup and preconcentration followed by HPLC-UV method were investigated for the simultaneous determination of seven low-dosed pesticides in saline concentrates for hemodialysis. The target compounds were ametryn, desmetryn, prometryn, terbutryn, molinate, triallate and butylate. Polyethylene (three different types), teflon, polyurethane and polystyrene, in powder form, were investigated as adsorbents for solid-phase extraction of the analytes from the saline samples.