Accurate analysis of trace earthy-musty odorants in water by headspace solid phase microextraction gas chromatography-mass spectrometry

• Published in: Journal of separation science Vol. 35; no. 12; pp. 1494 - 1501
• Main Authors: Ma, Kang, Zhang, Jin Na, Zhao, Min, He, Ya Juan
• Format: Journal Article
• Language: English
• Published: Weinheim Blackwell Publishing Ltd 01.06.2012; Wiley; Wiley Subscription Services, Inc
• Subjects: Analysis methods; Analytical chemistry; Applied sciences; Chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography; Drinking water and swimming-pool water. Desalination; Earthy-musty compounds; Exact sciences and technology; Gas chromatographic methods; Gas chromatography; Gas chromatography-mass spectrometry (GC-MS); Headspace solid-phase microextraction (HS-SPME); Linearity; Mass spectrometry; Natural water pollution; Odors; Pollution; Recovery; Separation; Spectrometry; Spectroscopy; Water samples; Water treatment and pollution; Trace analysis; Chemical analysis; Coupled method; Gas chromatography-mass spectrometry (GC-MS); Pyrazine derivatives; Tap water; Odorants; Chemical enrichment; Earthy-musty compounds; Off-flavor; Solid phase microextraction; Freshwater environment; Gas chromatography; Sample preparation; Surface water; Water quality; Water samples; Lakes; Headspace; Water pollution; Headspace solid-phase microextraction (HS-SPME); River water; Mass spectrometry
• ISSN: 1615-9306; 1615-9314
• DOI: 10.1002/jssc.201200029

A simple and sensitive method was developed for the simultaneous separation and determination of trace earthy‐musty compounds including geosmin, 2‐methylisoborneol, 2‐isobutyl‐3‐methoxypyrazine, 2‐isopropyl‐3‐methoxypyrazine, 2,3,4‐trichloroanisole, 2,4,6‐trichloroanisole, and 2,3,6‐trichloroanisole in water samples. This method combined headspace solid‐phase microextraction (HS‐SPME) with gas chromatography‐mass spectrometry and used naphthalene‐d8 as internal standard. A divinylbenzene/carboxen/polydimethylsiloxane fiber exposing at 90°C for 30 min provided effective sample enrichment in HS‐SPME. These compounds were separated by a DB–1701MS capillary column and detected in selected ion monitoring mode within 12 min. The method showed a good linearity from 1 to 100 ng L−1 and detection limits within (0.25–0.61 ng L−1) for all compounds. Using naphthalene‐d8 as the internal standard, the intra‐day relative standard deviation (RSD) was within (2.6–3.4%), while the inter‐day RSD was (3.5–4.9%). Good recoveries were obtained for tap water (80.5–90.6%), river water (81.5–92.4%), and lake water (83.5–95.2%) spiked at 10 ng L−1. Compared with other methods using HS‐SPME for determination of odor compounds in water samples, this present method had more analytes, better precision, and recovery. This method was successfully applied for analysis of earthy‐musty odors in water samples from different sources.