Analysis of Breast Milk to Determine Agent Orange Exposure
September 19th 2014Scientists in Vietnam have performed high-resolution gas chromatography coupled with high-resolution mass spectrometry (HRGC–HRMS) analysis of breast milk to determine the level of dioxin and furan exposure around the Da Nang Agent Orange hotspot in Vietnam. Agent Orange contamination is associated with elevated and persistent levels of dioxins and furans in the environment and are associated with the occurrence of birth defects among other side effects.
Detecting Microbial Compounds in Waterpipe Smoke
September 19th 2014Waterpipes have been used to smoke tobacco and other substances for more than four centuries, and are widely believed to be less harmful than cigarettes. In a new study published in the journal Science of the Total Environment, gas chromatography coupled to mass spectrometry (GC–MS–MS) was performed to show that waterpipe smoke can contain potentially harmful microbial compounds.
Improving MEKC–ESI–MS–MS Analysis of Synthetic Cathinones
September 19th 2014A team of scientists based in the Czech Republic has developed a micellular electrokinetic chromatography method coupled with tandem mass spectrometry (MEKC–ESI–MS–MS) that uses salts of perfluorocarboylic acid as the volatile background electrolyte (BGE). The method was applied to the determination of 12 drugs from the class of synthetic cathinones in urine samples. According to the paper published in the Journal of Chromatography A, the BGE used to form micelles did not affect the electron ionization efficiency of MS. (1)
Chiral Separation of I-MAMP and d-MAMP in Saliva
September 11th 2014Saliva is becoming ever more commonly used in drug testing over urine or blood samples because of its ease of collection. As such, existing testing methods are being adapted for application to accommodate a change in sample matrix. In a new study published in the Journal of Chromatography A, scientists from the National Institute on Drug Abuse (Maryland, USA) and the University of Maryland Baltimore (Maryland, USA) present the use of precolumn derivatization using N(?)-(2,4-dinitro-5-fluorophenyl)-l-alaninamide (Marfey?s reagent) prior to liquid chromatography–mass spectrometry (LC–MS) analysis for the quantitation of chiral amphetamines in plasma and saliva.1
Making it Crystal Clear: Detecting PPCPs in Water Using LC–MS
September 8th 2014This article describes a simple, more convenient method than traditional solid-phase extraction (SPE)-based methods for highly sensitive PPCP detection using triple quadrupole liquid chromatography–mass spectrometry (LC–MS–MS).
Evaluating Particle Size and Back Pressure in Peptide Mapping by UHPLC
September 8th 2014Ultrahigh-pressure liquid chromatography (UHPLC) columns are used in peptide mapping to improve the resolution of highly complex peptide mixtures. It is commonly assumed that small particle columns increase performance, but this is not always the case. This study presents a comparison of peak count, column length, and resolution between core–shell and fully porous UHPLC columns.
Pesticides in Fruit Determined by Fast LTP–Orbitrap–HR–MS
September 8th 2014A team of scientists from the University of Muenster and the University of Siegen in Germany has demonstrated the use of low temperature plasma desorption/ionization orbitrap high-resolution mass spectrometry (LTP–Orbitrap–HR–MS) for the analysis of pesticide residues in fruit.
5 Ways to Improve Your Split/Splitless Injection Technique
September 2nd 2014Split/splitless injectors typically vaporize a sample dissolved in a suitable organic solvent under increased temperature. The sample vapors are entrained into the carrier gas flow inside a "liner" or "sleeve" within the inlet and from there pass into the column or out of the inlet via the "split" line/valve.
The Role of Chromatography Data Systems in Fraud and Falsification
September 1st 2014Chromatography data systems (CDSs) have had a starring role in many regulatory citations involving falsification and fraud in analytical laboratories regulated by Good Manufacturing Practices (GMP). In this instalment of "Questions of Quality" we will examine the citations and identify the technical and procedural controls required to ensure data integrity within these systems. Although focused primarily on the pharmaceutical industry, the principles described here are applicable to all laboratories working to established quality standards.