In recent years, there has been a rapid proliferation of smokeless products with a wide range of nicotine content and flavoring formulations that may appeal to new users and existing cigarette smokers. The CDC nicotine method, which employs gas chromatography-flame ionization detection (GC-FID), provides a robust means for measuring nicotine in smokeless tobacco. However, several compounds, ide...

The San Francisco Estuary Regional Monitoring Program initiated surveillance monitoring to identify previously unmonitored synthetic organic contaminants in the San Francisco Estuary. Organic extracts of water samples were analyzed using gas chromatography-mass spectrometry in full scan mode. The major contaminant classes identified in the samples were fire retardants, pesticides, personal care...

different solvent extracts of a red algae, hypnea flagelliformis,and two brown algae, cystoseira myrica and sargassum boveanum, collected from the persian gulf coast were subjected to different bioassays including: 1,1-diphenyl-2-picrylhydrazyl (dpph) free radical scavenging assay, antibacterial and antifungal activity by thin layer chromatography (tlc)-bioautography, agar disc diffusion (add) ...

Samples of marketed Lauha bhasma from different manufactures were evaluated chemically. Apart from the 81 -85% iron content, the 15-19% other constituents were determined therein. Ferrous ferric and total iron in a single aliquot were determined spectrophotometrically, Qualitative and chromatographic analysis indicate the presence of sodium, potassium, calcium copper and cobalt in the samples, ...

A sequential separation scheme has been devised for the quantitative analytical separation of 27 different metal ions. Five different Chromatographic and ion-exchange columns are used to separate the metal ions into groups. The metal ions of each group are eluted separately from each column by means of selective eluents. Following separation, the metal ions are determined by titrimetry, flame s...

In 2000, human skeletal remains were discovered in Split (Croatia). As archaeologists confirmed, it was an ancient skeleton accompanied by ceramics and bracelet characteristic for late Roman period whose possible violent death was excluded. The bone sample was radiocarbon dated by AMS to 1750 years. DNA was successfully extracted from the bone sample and subsequently typed using mt DNA and STR ...

The percentage composition of Al13, [AlO4Al12(OH)24(H2O)12]7+, in water treatment coagulants is an important criterion in the development and use of polymeric coagulants. Polymeric coagulants are generally used in cold climates or with highly turbid waters. Size exclusion chromatography flame atomic absorption spectrometry (SEC-FAAS) can separate Al13 and monomeric Al within 6 min. The percenta...

Extracts of gasoline and diesel vehicle exhaust and ambient air particles were fractionated into five fractions according to polarity on a silica gel column. Two medium polar fractions showing high genotoxic activity in the Ames test were further subfractionated, using normal-phase high-performance liquid chromatography. Chemical analyses were performed by means of gas chromatography combined w...

The cloud-point methodology was successfully employed for the preconcentration of heavy metal cations at trace levels from aqueous samples prior to flame atomic absorption spectrometry (FAAS). Cations were taken into a complex with 8-quinolinol in an aqueous non-ionic surfactant, Triton X-114, medium and concentrated in the surfactant rich phase by bringing the solution to the cloud-point tempe...

Copper-based fungicides can be effectively digested by treatment with a mixture of concentrated sulfuric and nitric acid in exactly 15 minutes for the rapid determination via copper using flame atomic absorption spectrometry (AAS). Under optimum conditions, the results of copper fungicide analysis were consistent to those obtained by the AOAC’s recommended method. Recovery values ranged from 98...