Plasma-modified filters improve recovery of viable fungal spores for culture and DNA analysis

Abstract

Abstract This proof-of-concept study evaluates plasma-modified polyethylene terephthalate (PET) filters for fungal bioaerosol collection and downstream culture and molecular analyses. Filters were plasma-coated using either 2-methyl-2-oxazoline (POX) or perfluorooctane (PFO), to enhance fungal spore adhesion and recovery using Aspergillus niger and Rhodotorula glutinis as representative of filamentous and yeast-like fungal species, respectively. Optimal capture was achieved at 15 L/min for 30 min, with saturation reached at 38 mg using biomass from four to five colony plates. Viability tests confirmed that spores collected on PFO and non-coated (NC) filters retained the ability to germinate, whereas POX coatings inhibited regrowth, indicating an antifungal surface effect. Molecular analyses demonstrated that 14–16 mg of captured biomass yielded sufficient DNA for downstream analyses. The internal transcribed spacer (ITS) region amplified using PCR produced clear amplicons (~ 550 base pair (bp)) across all tested species. Sequencing provided accurate species identification with 99–100% similarity to GenBank reference sequences, verifying that plasma coatings did not compromise DNA quality, amplification efficiency, or sequencing integrity. These findings establish plasma-polymer-coated PET filters as effective and cultivation- and PCR-compatible tools for fungal bioaerosol collection and define practical operating parameters for their use in environmental assessments. Key points • Plasma-coated PET filters support integrated fungal bioaerosol analysis. • PFO-coated filters enabled recovery of viable fungal spores. • Recovered fungal biomass was suitable for PCR and ITS sequencing.