Systematic Quality Assurance/Quality Control Framework for a Volatile Organic Compound Real-Time Monitoring Instrument, Autonomous Rugged Optical Multigas Analyzer for VOCs
Publications
03rd Jun 2025
Working with collaborators at the University of Kentucky, Entanglement Technologies has demonstrated a quality assurance/quality control framework for AROMA-VOC. The results, published in the journal ACS Omega, are important in validating new technologies for environmental monitoring. Check out the abstract here, and then the full article.
Abstract
This study presents a systematic quality assurance/quality control (QA/QC) framework for new technology adopters to validate environmental monitoring instruments when consistent, standardized validation and calibration procedures do not readily exist. This QA/QC framework is especially relevant for newly developed environmental monitoring instruments prior to deployment in field settings as part of environmental site investigations. Key QA/QC parameters used in the framework include repeatability, intermediate precision, reproducibility, linearity, limits of detection (LOD), limit of quantification (LOQ), trueness, and recovery. The QA/QC framework is demonstrated on the autonomous rugged optical multigas analyzer for VOCs (AROMA-VOC), a technology that employs cavity ring-down spectroscopy (CRDS) with preconcentration and chromatographic separation prior to CRDS detection. QA/QC protocols for nine VOCs, and results for AROMA-VOC were compared with laboratory-based gas chromatography/mass spectrometer (GC–MS). Results demonstrated high linearity (R2 > 0.95) and low LOQ values (0.0004 ± 0.0002–0.0455 ± 0.0192 μg/L). The instrument also exhibited ranges of LOD at least an order of magnitude lower than that of the referenced GC–MS. AROMA-VOC demonstrated acceptable precision [repeatability, intraday relative standard deviation (RSD %): 1.72–12.1%; intermediate, interday RSD %: 2.01–10.93%] and substantial recovery (104.8% to 212.4%). Interlaboratory testing also concluded that AROMA-VOC can produce consistent detections (R2 > 0.90). The z-score findings suggested that the performance of the instrument was satisfactory, with the exceptions of xylenes and 1,3-butadiene. Overall, using the systematic QA/QC framework presented in this study, AROMA-VOC is shown to be a robust method for volatile organic compound analysis.