High-efficiency headspace sampling of volatile organic compounds in explosives using capillary microextraction of volatiles (CMV) coupled to gas chromatography-mass spectrometry (GC-MS).
Anal Bioanal Chem
; 406(8): 2189-95, 2014 Mar.
Article
em En
| MEDLINE
| ID: mdl-24141390
ABSTRACT
A novel geometry configuration based on sorbent-coated glass microfibers packed within a glass capillary is used to sample volatile organic compounds, dynamically, in the headspace of an open system or in a partially open system to achieve quantitative extraction of the available volatiles of explosives with negligible breakthrough. Air is sampled through the newly developed sorbent-packed 2 cm long, 2 mm diameter capillary microextraction of volatiles (CMV) and subsequently introduced into a commercially available thermal desorption probe fitted directly into a GC injection port. A sorbent coating surface area of â¼5 × 10(-2) m(2) or 5,000 times greater than that of a single solid-phase microextraction (SPME) fiber allows for fast (30 s), flow-through sampling of relatively large volumes using sampling flow rates of â¼1.5 L/min. A direct comparison of the new CMV extraction to a static (equilibrium) SPME extraction of the same headspace sample yields a 30 times improvement in sensitivity for the CMV when sampling nitroglycerine (NG), 2,4-dinitrotoluene (2,4-DNT), and diphenylamine (DPA) in a mixture containing a total mass of 500 ng of each analyte, when spiked into a liter-volume container. Calibration curves were established for all compounds studied, and the recovery was determined to be â¼1 % or better after only 1 min of sampling time. Quantitative analysis is also possible using this extraction technique when the sampling temperature, flow rate, and time are kept constant between calibration curves and the sample.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
Anal Bioanal Chem
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
Estados Unidos