Automated Needle Trap Heart-Cut GC/MS and Needle Trap Comprehensive Two-Dimensional GC/TOF-MS for Breath Gas Analysis in the Clinical Environment

Abstract

This study was intended to evaluate low-volume (20 mL) multibed needle trap (NTD) sampling combined with heart-cut gas chromatography/mass spectrometry (GC/MS) and comprehensive two-dimensional gas chromatography/time-of-flight mass spectrometry (GC x GC/TOF-MS) for trace gas analysis under clinical conditions. NTDs, high-throughput automatic desorption and separation systems, were tested in vitro and within a study in 11 patients undergoing cardiac surgery with respect to reproducibility, reliability, and clinical applicability. NTD-heart-cut GC/MS analysis of standard mixtures containing different volatile organic compounds (VOCs) yielded relative standard deviations (RSDs) from 4.0% to 18.5%. Substance adsorption was stable for 1 day if NTDs were closed on both ends and was stable for approximately 7.8 h when NTD tip ends had to be left open during autosampler storage. Even in the presence of high concentrations of contaminants linearity of heart-cut GC/MS was conserved. In patients' breath potential biomarkers could be determined even in the presence of very high concentrations of sevoflurane. Profiles of blood-borne biomarkers, intravenous drugs, and clinical contaminants were characterized. Comprehensive GC x GC/TOF-MS may be used as a screening tool for new biomarkers, if patterns are generated from deconvoluted normalized areas. Needle trap sampling in combination with hyphenated chromatographic techniques can thus be used to provide well-tailored solutions for complex problems occurring in clinical breath analysis.

Influence of Ethanol on Breath Acetone Measurements Using an External Cavity Quantum Cascade Laser

“…Elevated breath acetone concentrations have been reported in patients presenting with diabetes [4], persons dieting (i.e., Atkins Diet) or fasting [5,6], persons after exercising [7] or in patients after cardiovascular surgery due to metabolic stress [8].…”

Allergic asthma exhaled breath metabolome: A challenge for comprehensive two-dimensional gas chromatography

“…To the best of our knowledge, GC × GC-ToFMS methodology has never been reported before to study allergic asthma exhaled breath volatile composition. However, GC × GC-ToFMS has been used with multibed sorption trap for exploring human exhaled breath volatile composition [10], and searching potential biomarkers for active smoking [11], and combined with automated needle trap for breath analysis of patients undergoing cardiac surgery [12]. These studies revealed the potential of this technique in breath analysis.…”

Needle-type Extraction Device Designed for Rapid and Sensitive Analysis in Gas Chromatography

“…The extracted analytes can then be thermally desorbed in the heated GC injection port, typically without a desorption solvent. 31,33,34 For desorption of the extracted analytes from the sorbent, there are two types of desorption methods: one uses carrier gas flow as the desorption gas, [32][33][34][35][36][37] while another way is not using a carrier gas. When not using a carrier gas, the flow of an inert gas, supplied from a gas tight syringe, was used as the desorption gas.…”

“…35 Trefz et al investigated the sample flow rate and sample volume, along with the effect of humidity for breath analysis using a MA/EGDMA-packed needle and a triple-bed extraction needle. 49 They reported that the triple-bed extraction needle was not affected by the humidity.…”