Design of solid phase microextraction patches for the detection of volatile metabolites associated with Burkholderia cepacia

Burkholderia cepacia, a gram-negative bacillus, is widely recognized as an emerging pathogen responsible for nosocomial infections in patients with cystic fibrosis (CF). The conventional culture-based method takes 5-7 days, posing a challenge for rapid bacterial identification. Here, we developed a thin-film solid phase microextraction (TF-SPME) device by coating a fiberglass sheet with hydrophilic-lipophilic balanced (HLB) particles and polydimethylsiloxane (PDMS) polymers, exploiting an automatic film applicator to maintain coating uniformity. The coated sheet was trimmed into multiple microextraction sampling tools, and the individual patches were optimized using a McReynolds standard solution containing benzene, 2-pentanone, pyridine, octane, 1-nitropropane, and 1-pentanol compounds. Headspace sampling was performed to capture the highly volatile compounds, whereas comparatively less volatile and polar compounds were extracted through the direct immersion by the microextraction patches. The TF-SPME patches were desorbed in a gas chromatography triple quadrupole mass spectrometer, and the chromatogram revealed the emission of 34 metabolites associated with B. cepacia pathogen during the growth phase. This study demonstrated the feasibility of the utilization of simple, cost-effective microextraction patches for the extraction of B. cepacia specific metabolites. Moreover, the greenness assessment score (BAGI score = 70 and AGREE = 0.68) established the sustainability of the sample preparation technique. Further validation with clinical specimen may facilitate the future clinical research for the identification of B. cepacia. KEY POINTS: • Fiberglass-based polymer-coated microextraction patches were fabricated • Fabricated patches were optimized for capturing volatile metabolites • Burkholderia cepacia was screened through in-vitro metabolic profiling by patches.