|Simultaneous multi-determination and transfer of eight pesticide residues from green tea leaves to infusion using gas chromatography|
Sung-Woo Kim, Soon-Kil Cho, A. M. Abd El-Aty, Md. Musfiqur Rahman, Jeong-Heui Choi, Jae-Han Shim
Acetonitrile was used as the extraction solvent with sodium chloride to enhance the partitioning of analytes into the organic phase. Recovery indicated good method accuracy and repeatability, and was within the acceptable range for residue determinations. The mere presence of pesticide residues in tea does not necessarily mean that the tea has become toxic and would pose a health hazard. We revealed that only a negligible or small percentage of pesticides in tea is transferred to the infusion.
|Matrix enhancement effect: A blessing or curse for gas chromatography?|
Jae-Han Shim, Md. Musfiqur Rahman, A. M. Abd El-Aty
A sharp, narrow, and sensitive peak is a pre-condition for a sensitive GC analysis. Therefore, a protectant is needed to protect the analyte from any type of distortion for integration and to prevent overestimation. Existing solutions do not overcome these problems completely due to limitations. As the matrix enhancement problem originated from matrix components, its solution should come from similar components.
|HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY METHOD FOR DETERMINATION OF LIPOIC ACID IN THE FORM OF 2-S-PYRIDINIUM DERIVATIVE|
Chwatko G. (1), Krawczyk M. J. (1), Iciek M. (2), Bilska-Wilkosz A. (2), Marcykiewicz B. (3), Glowacki R. (1)
* The method can be used for routine clinical monitoring of LA in human plasma and urine.
* The method was validated for urine and plasma samples.
* The imprecision, expressed as relative standard deviation value, were within range 0.8-7.7% and 0.9-6.2% for plasma and urine samples, respectively.
* The analytical recovery were from 97.3 to 117.0% for plasma and from 96.5% to 111.5% for urine samples.
|MS Data Processing With Full Flexibility Of Universal Processing Software|
Frans Schoutsen, Barbara van Cann, Vincent Jespers, Michal Godula
Liquid Chromatography (LC) in combination with triple quadrupole Mass Spectrometry (MS) is more and more a common analysis technique in routine laboratories. Especially when using MS/MS selected reaction monitoring (SRM) for a large number of components data handling can be a bottle neck. This poster will show MS data processing of pesticides in water samples using an already established chromatography data system which is now also capable of processing large quantities of MS data.
|Analysis of Dithiocarbamate Pesticides by GC-MS|
Soma Dasgupta1,2, Sumaiyya Mujawar1, Kaushik Banerjee1, Hans-Joachim Huebschmann3, Paul Silcock4
Analysis of dithiocarbamate pesticides (DTCs) using an optimized GC-MS method is described. DTCs are not stable and cannot be extracted or analyzed directly. The purpose of this work was develop a reliable method for identification and quantification of residues.
|Analysis of Multiresidue Pesticides Present in Ayurvedic Churna by GC-MS/MS|
Manoj Surwade, Sunil T Kumar, Aarti Karkhanis, Manish Kumar, Soma Dasgupta, Hans-Joachim Huebschmann, Paul Silcock, Thermo Fisher Scientific
Analysis of Herbal powders or ‘churnas’ using an optimized GC-MS/MS method is described. As they have high amount of matrix co-extractives, they pose critical analytical problems. The purpose of this work was overcome the effect of the matrix and develop a reliable method.
|Automated Solid-Phase Extraction of Oraganochlorine Pesticides from Drinking Water|
Frans Schoustsen and Pranathi R Perati
A new method was developed to automate the capture and elution of Organochlorine pesticides from drinking water. The concentrated analytes were then analyzed by GC with Electron Capture Detection (ECD).
|GC-MS/MS Analysis of Pesticide Residue in Green Tea Extracted by QuEChERS with Acetonitrile as Final Solvent|
Cojocariu C., Morgan P., Silcock P., Godula M
QuEChERS involves an initial step when a few grams of the sample are extracted with acetonitrile followed by a clean-up step (with dispersive-SPE) used to remove, to a certain extent, unwanted matrix compound (such as pigments, sugars, organic acids). With QuEChERS, the final extract ends up with the pesticides in acetonitrile, which, being polar solvent, can be
problematic in GC-MS.
|Increasing Extraction Efficiency of Pesticides and Dioxins from Wet Samples Using a Novel Polymer During Accelerated Solvent Extraction|
Katerina Bousova, Pranathi Perati, Rahmat Ullah, Kannan Srinivasan
Thermo Scientific™ Dionex™ ASE™ Prep MAP is a proprietary polymer designed to remove moisture and increase extraction efficiencies from wet samples including soils, tissues and food products. This unique formulation allows moisture removal under a variety of ionic strength conditions and accelerated solvent extraction conditions.