Application Note 009: Monitoring materials and processes for VOCs at high and trace levels
This Application Note shows examples that demonstrate the considerable savings of labour and cost that can be achieved using thermal desorption to analyse VOCs emitted from materials, including polymers, foods, pharmaceuticals and construction products.
Application Note 014: Monitoring labile, high-boiling organic vapours such as those found in cleanroom air in semiconductor plants
This Application Note demonstrates the compatibility of Markes’ thermal desorption (TD) technology with challenging semi-volatile organic compounds (SVOCs) such as isobornyl methacrylate and dioctyl phthalate. In particular, it is shown how re-collection and repeat analysis capability can overcome the one-shot limitation of traditional TD technology.
Application Note 017: The GC–FID sensitivity of the UNITY thermal desorber
This Application Note demonstrates the ability of the UNITY™ thermal desorber in conjunction with GC–FID to detect as little as 30 pg of benzene, equating to a concentration of 10 ppt in 1 L of air.
Application Note 024: Overcoming the ‘one-shot’ limitation of thermal desorption by the re-collection of desorbed samples
In this Application Note, we demonstrate how sample splitting and re-collection can overcome the ‘one-shot’ limitation of thermal desorption, providing a powerful tool for method development and validation.
Application Note 028: Optimising analytical performance and extending the application range of thermal desorption for monitoring air indoors and inside vehicle cabins
This Application Note describes considerations relating to analyte retention efficiency, desorption efficiency, artefacts, band broadening and analyte/system stability during the development and validation of thermal desorption procedures. Examples of optimum method performance in terms of precision, linearity and sensitivity are presented.
Application Note 030: Certified reference materials for analysis of VOCs in air by TD–GC
This Application Note describes the use of certified reference standards and methods to estimate analytical bias in thermal desorption (TD)–GC analyses.
Application Note 032: The analysis of sulfur compounds using on-line and off-line TD–GC
This Application Note demonstrates how Markes’ thermal desorption (TD) technology is compatible with trace-level sulfur compounds. Examples include the analysis of sulfur standards using methods based on on-line methods, canisters and tubes, and the detection of sulfur compounds in landfill gas.
Application Note 034: Monitoring trace-level high-boiling compounds (triethyl phosphate and methyl salicylate) in air
This Application Note demonstrates the long-term stability of the UNITY™ thermal desorber with regard to the off-line analysis of two high-boiling analytes, methyl salicylate and triethyl phosphate.
Application Note 035: Thermal desorption of dioctyl phthalate and other plasticisers
This Application Note demonstrate that Markes’ UNITY™ thermal desorber gives quantitative and reproducible results for desorption of high-boiling plasticisers such as dioctyl phthalate. System performance is further verified for this difficult application by the demonstration of re-collection and repeat analysis.
Application Note 039: Analysis of semi-volatile phosphorus pesticides by thermal desorption and method validation using sample re-collection
This Application Note demonstrates the quantitative performance possible with Markes’ thermal desorption systems for reactive, semi-volatile compounds such as phosphorus pesticides. The data also illustrates the use of re-collection technology as a tool for method validation.
Application Note 046: Monitoring organic vapours in air – A comparison of thermal desorption and carbon disulfide (CS2) extraction
This Application Note compares thermal desorption analysis of sorbent tubes with solvent extraction for the detection of volatile organic compounds in air. Particular benefits highlighted are the lower detection limits, higher reproducibility and cost savings, as well as avoiding the health & safety issues inherent to the use of CS2.
Application Note 053: Quantitative recovery and method validation of high-boiling SVOCs using TD–GC–MS
This Application Note demonstrates the excellent performance of Markes’ thermal desorbers for the analysis of semi-volatile organic chemicals (SVOCs) from standard solutions by thermal desorption (TD)–GC–MS. It also shows the application and benefit of sample re-collection and analysis for simple validation of analyte recovery.
Application Note 061: Diffusion-locking technology
This Application Note provides a detailed description of the principles of diffusion-locking, and how it can be applied to enhance both sorbent tube sampling and the automation of thermal desorption.
Application Note 064: Simultaneous TD–GC analysis of VOCs and SVOCs
This Application Note shows that Markes’ thermal desorption (TD) technology, incorporating a main heated valve and backflush desorption of the focusing trap, facilitates simultaneous analysis of VOC and SVOCs, such as those of relevance to material emissions testing. This capability is validated using the secure sample re-collection facility inherent to Markes’ systems.
Application Note 079: Air monitoring – The advantages and applications of canisters and tubes
This Application Note discusses the application areas of canister-based and sorbent-tube-based sampling for volatile organic compounds (VOCs), and the advantages and limitations of each approach.
Application Note 082: TubeTAG – Enhanced tracking of sample- and tube-related information for thermal desorption
This Application Note describes TubeTAG™, Markes’ radio-frequency ID technology for thermal desorption tubes. The technology allows information about sample type and analytical conditions to be associated with the sample for the lifetime of the tube, so aiding sample tracking and analytical quality control.
Application Note 108: Optimisation of TD methods to minimise carryover of semi-volatiles during direct desorption of a polymer
This Application Note demonstrates the exceptionally low levels of carryover achievable for the semi-volatile organic compound caprolactam, when carrying out direct desorption of polyamide pellets with Markes International’s TD-100 automated thermal desorber.
Application Note 109: Improving productivity and reducing costs by off-line sorbent tube conditioning
Rigorous conditioning of sorbent tubes is an essential part of any sampling and analysis protocol. This Application Note explores the cost savings and productivity enhancements that can be made by off-line conditioning with Markes’ TC-20 or TC-20 TAG multi-tube conditioners, rather than on-line with the thermal desorber itself. In particular, it focuses on the revenue resulting from running more analytical samples, the cost-effectiveness of increasing sample capacity by this approach, and the benefits that stem from using nitrogen rather than helium.