Determination of Sulfur in Natural Gas by ASTM Method D 6228-11
September 1st 2012Natural gas and other gaseous fuels contain varying amounts and types of sulfur compounds which can be corrosive to equipment and can inhibit or destroy gas processing catalysts. Small amounts of sulfur odorants are added to natural gas and liquefied petroleum gases (LPGs) for safety purposes. Accurate measurement of sulfur species ensures proper process operation and odorant levels for public safety.
Simplified Yet Sensitive Determination of Aniline and Nitroanilines
September 1st 2012Aniline is an organic compound widely used in the polymer, rubber, pharmaceutical, and dye industries. Aniline and its derivatives (e.g., nitroanilines) are suspected carcinogens and are highly toxic to aquatic life. Because these compounds are thermolabile and polar, the traditional analytical methods require a derivatization step prior to GC analysis.
Fast Screening Methods for Steroids by HPLC with Agilent Poroshell 120 Columns
September 1st 2012Selectivity is the most powerful tool to optimize separations in HPLC. This parameter is changed by using different bonded phases or by changing the mobile phase. In this work, Poroshell 120 columns with highly efficient 2.7 ?m superficially porous particles and the Agilent 1260 Infinity Series LC Multi-Method Solution were used to quickly evaluate method development choices for the analysis of steroids.
Molecular Weight Determination of LMWH SEC–MALS vs. SEC–UV-RI
September 1st 2012Low-molecular-weight heparins (LMWHs) are obtained by fractionation or depolymerization of natural heparins. They are defined as having a mass-average molecular weight of less than 8000 and for which at least 60% of the total weight has a molecular mass less than 8000.
Analysis of Intact Proteins on a Thermo Scientific Accucore 150 C4 HPLC Column
September 1st 2012This application note demonstrates the analysis of intact proteins using a Thermo Scientific Accucore 150-C4 (150 ? pore diameter) HPLC column. Analysis of six proteins ranging in mass from 6 to 45 kDa is carried out in 15 min with pressures compatible with conventional HPLC instrumentation.
Creation of a New IMS Analyzer Platform with High Resolving Power
September 1st 2012Ion mobility spectrometry (IMS) has become widely accepted for the detection of chemical warfare agents, explosives, and narcotics as well as for pharmaceutical quality control and pesticide screening of food. Most currently available commercial IMS units have a resolving power of 10–60.
Unique Effects of Two Mobile Phase Alcohols on the RegisPack CLA-1 Chiral Stationary Phase (CSP)
September 1st 2012Typical chiral stationary phase (CSP) screening paradigms utilize a single alcohol component as co-solvent in its mobile phase. Recent unexpected observations have demonstrated that mixed-alcohol mobile phases can enhance or even introduce peak resolution when none existed in a mono-alcohol system.
Fast Petroleum Hydrocarbons Analysis for Underground Storage Tank Monitoring
September 1st 2012Underground storage tanks (USTs) for various petroleum-based substances such as gasoline, diesel fuel, and fuel oil are monitored for leaks as authorized by the Resource Conservation and Recovery Act (RCRA).
Separation of 20 Amino Acids by Polymer-Based Amino HILIC Column
September 1st 2012Determination and quantification of amino acids are important in many fields. For the HPLC analysis of amino acids, cation exchange mode method has been used with post-column derivatization. Recently, use of reversed-phase mode method is also increasing. However, because of amino acids' hydrophilic nature, they are usually not well retained and have less selectivity by reversed-phase mode without pre-column derivatization steps. In contrast, HILIC mode is an ideal separation mode for hydrophilic compound analysis.