chromatographic Articles

  • ChlorAC Buffer

    Introduction Trace analysis of carbamate insecticide residues in water is a routine requirement in the U.S. Since several of the common carbamates — Carbaryl, Oxamyl, Hydroxycarbofuran — are labile in water due to oxidation or hydrolysis, the samples and standards must be preserved in order to obtain valid results. USEPA Method 531.1 specifies pH adjustment, ...


    By Pickering Laboratories, Inc.

  • Waters HPLC & UHPLC Application Notes at Your Finger Tips

    Summary A quick reference notebook to Waters HPLC/UHPLC application note highlights.   140 application notes covering a wide range of markets, such as Pharma, Food, and Health Science. Condensed one page format highlighting experimental conditions and chromatographic results. Tips on how to choose the best column to deliver ...


    By Waters Corporation

  • The Extraction of Glycols From Water Using ENVI-Carb™ Plus Solid Phase Extraction Cartridges

    The analysis of glycols such as propylene and ethylene glycol from water samples is traditionally done by direct aqueous injection into a gas chromatograph. Aqueous injections are problematic in GC analysis due to issues such as the large expansion volume of water in the inlet, increased carryover, and elevated detection limits. In this work, we have evaluated a unique carbon adsorbent, ENVI-Carb ...


    By MilliporeSigma

  • Testing of Pharmaceutical & Cosmetic Raw Materials & Final Product Formulations for CODEX, USP/NF & BP Regulations

    There are STANDARD Guidelines used to define the Identification and Purity of compounds used in Pharmaceutical and Cosmetic formulations, as well as the final Products. These protocols are described in great detail in the various Monographs of the United States and British Pharmacopoeias, the National Formulary (USP/NF and BP), the International FAO/WHO Codex (CODEX) and other Regulatory ...


    By Buck Scientific Inc

  • Semi-volatile organics in drinking water using EPA method 525.2 optimized for greater sensitivity

    The US EPA Drinking Water Manual contains the methods used to identify and quantify regulated and unregulated organic drinking water contaminants. Included in this manual is Method 525.2, a Gas Chromatographic/ Mass Spectrophotometric (GC/MS) technique for the determination of semi-volatile organic compounds. Method 525.2 can be used for the identification and quantification of a group of ...


    By PerkinElmer, Inc.

  • o-Phthalaldehyde Reagent

    Introduction Primary amines form highly fluorescent adducts when reacted with o-Phthalaldehyde (OPA) and a mercaptan under basic conditions. At a pH>9 and ambient temperature, reaction is generally complete within 30 seconds. The products of this reaction, 1-alkyl-2-alkylthio-substituted isoindoles, exhibit optimal excitation at 330 nm and maximal emission at 465 nm. The reagents ...


    By Pickering Laboratories, Inc.

  • Low-Chemical Solution for Juice Demineralization - Case Study

    PROJECT DETAILS LOCATION Vicenza, Italy CUSTOMER Italian Fruit Juice Company SOLUTION Juice Demineralization Plant TECHNOLOGY 4SMB Chromatography At an Italian organic foods plant, Fluence installed 4SMB chromatography for a low chemical, economical solution ...


    By Fluence Corporation

  • Radiolytic studies on some organic dyes in aqueous solutions

    Radiolytic studies on four aqueous dye solutions were carried out. Colour bleaching of the dye solutions upon irradiation was followed by quantitative TLC. Spot comparison methods were used to determine the dependence of the Spot Area Weight (SAW) of the chromatographic spots on the spot content. A good linear relationship was obtained. The percentage changes of SAW values of the analysed dye ...


    By Inderscience Publishers

  • Volatile organic compounds emitted from hardwood drying as a function of processing parameters

    During the drying of wood, volatile organic compounds are emitted. These emissions contribute, in the presence of nitrogen oxides and sunlight, to the formation of ground level ozone and other harmful photo-oxidants. Emissions of volatile organic compounds from the drying of birch sawdust in a spouted bed were analyzed with a flame ionization detector and with a gas chromatograph-mass ...

  • Accurate Characterization of Polymers and Additives in Personal Care Products and Packaging by Fast-Scanning IR

    You can’t buy anything today without a package. Think about it. Blister packs, cellowraps, shrink wraps, barrier bags, vapor films, UV-blocking films, heat-blocking films, tinted plastics, filled polymers, biodegradable bags, structural plastics, laminated films, moisture barrier films ….. ad infinitum (literally). Industries that manufacture plastics or utilize plastics need to characterize ...


    By Buck Scientific Inc

  • The NILU tracer gas technique

    A tracer gas technique has been developed by the Norwegian Institute for Air Research (NILU) to study emission rates, dilution and diffusion of gases. The technique has been applied in several countries to quantify diffuse VOC leakages from refineries, petrochemical plants and oil production platforms.  The tracer gas techniqueThe dual tracer gas system developed by NILU has been applied in ...

  • Degradation of Fumonisin B1 by a Bacterial Strain Isolated from Soil

    Abstract  A mixed microbial culture degrading fumonisin B l was obtained from soil samples using an enrichment culture procedure. A bacterial isolate from the enrichment culture (strain NCB 1492) degraded fumonisin B1 after incubation for 3 h, as indicated by TLC and HPLC analysis. On the basis of the sequence analysis of 16S rDNA, strain NCB 1492 was related to the Delftia/Comamonas group. ...


  • Electrochemical degradation of 2,5-dichloro-1,4-phenylenediamine by anodic oxidation

    Electrochemical degradation of 2,5-dichloro-1,4-phenylenediamine (DP) in aqueous solution by anodic oxidation was investigated. Linear sweep voltammograms and cyclic voltammograms were studied. The influence of operating parameters on electrochemical oxidation of DP was studied as a function of the current density, initial pH, and initial concentration of DP. The degradation kinetics analysis ...


    By IWA Publishing

  • Monitor Sulfur Compounds in Petroleum Chemical, Environmental, and Other Samples, Using a Special-Purpose Capillary GC Column

    Measurement of sulfur compounds is important to petroleum chemical analysts for several reasons, including a need to monitor odor problems and prevent catalyst poisoning.  Quantification of sulfur compounds is also important to environment analysts and to food, beverage and fragrance analysts for similar reasons.  Analyses of sulfur compounds can be complicated by the inability to ...


    By MilliporeSigma

  • Fenton degradation of Cartap hydrochloride: identification of the main intermediates and the degradation pathway

    The advanced oxidation of Cartap hydrochloride (Cartap) promoted by the Fenton system in an aqueous medium was investigated. Based on total organic carbon, chemical oxygen demand and high-performance liquid chromatography, the oxidation of Cartap is quite efficient by the Fenton system. Its long chain is easily destroyed, but the reaction does not proceed to complete mineralization. Ion ...


    By IWA Publishing

  • Polyether antibiotics monensin, narasin, & salinomycin

    Polyether antibiotics, such as Monensin, Narasin, and Salinomycin, in raw material, premix, liquid supplements, and final feeds, are best quantified using a high-performance liquid chromatograph equipped with a post-column reactor. The polyether antibiotics react, post-column, with Vanillin in the presence of Sulfuric acid, and the resulting products can be detected at 520 nm. However, this ...


    By Pickering Laboratories, Inc.

  • Hydrogen Performance for Carrier Gas

    Owing to the worldwide helium shortage, many labs are facing supply difficulties of helium, one of the most commonly used carrier gases and as a consequence are facing rapid price increases. Many chromatography labs are therefore looking for alternative carrier gases and for many GC applications, hydrogen provides a good, in some cases better, alternative to helium. The perceived danger of having ...

  • Quality control of immunoassays for pesticide residues

    I. Abstract Quality control of any analytical method is integral to its ability to produce reliable results. To adequately control a method, one must first understand the sources of variability. Some sources of error in an immunochemical method are similar to those of a traditional chromatographic technique. Immunoassays also present some unique potential error sources along with novel ...


  • High-Performance Liquid Chromatography for Determination of N-Nitrosodimethylamine in Water

    High-performance liquid chromatography (HPLC) was applied for aqueous determination of Nnitrosodimethylamine (NDMA). A fluorescence derivatization technique was adopted to enhance detection using HPLC. Derivatization with dansyl chloride was optimized for excitation and emission wavelengths (340 and 530 nm, respectively), pH (9-12), and concentration of dansyl chloride (500 mg/L). An instrumental ...

  • A study of polycyclic aromatic hydrocarbons in airborne particulate matter in central Taiwan

    Two sampling sites in central Taiwan, at Hungkuang University (HKU) and Tunghai University (THU), were chosen to contrast the content of polycyclic aromatic hydrocarbons (PAHs) in the atmosphere from November 2000 to April 2001. PAHs that arise from incomplete combustion of organic materials, especially fossil fuels, are the major toxic pollutants in central Taiwan. This study aimed to analyse ...


    By Inderscience Publishers

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