Enhanced and copper concentration dependent virucidal effect against SARS-CoV-2 of electrospun poly(vinylidene difluoride) filter materials
Hanna Bulgarin,
Thomas Thomberg,
Andres Lust,
Jaak Nerut,
Miriam Koppel,
Tavo Romann,
Rasmus Palm,
Martin Månsson,
Marko Vana,
Heikki Junninen,
Marian Külaviir,
Päärn Paiste,
Kalle Kirsimäe,
Marite Punapart,
Liane Viru,
Andres Merits,
Enn Lust
Affiliations
Hanna Bulgarin
Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
Thomas Thomberg
Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia; Corresponding author
Andres Lust
Institute of Pharmacy, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
Jaak Nerut
Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
Miriam Koppel
Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
Tavo Romann
Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
Rasmus Palm
Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia; Department of Applied Physics, KTH Royal Institute of Technology, 10691 Stockholm, Sweden
Martin Månsson
Department of Applied Physics, KTH Royal Institute of Technology, 10691 Stockholm, Sweden
Marko Vana
Institute of Physics, University of Tartu, W. Ostwald 1, 50411 Tartu, Estonia
Heikki Junninen
Institute of Physics, University of Tartu, W. Ostwald 1, 50411 Tartu, Estonia
Marian Külaviir
Institute of Ecology and Earth Sciences, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
Päärn Paiste
Institute of Ecology and Earth Sciences, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
Kalle Kirsimäe
Institute of Ecology and Earth Sciences, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
Marite Punapart
Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
Liane Viru
Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
Andres Merits
Institute of Technology, University of Tartu, Nooruse 1, 50411 Tartu, Estonia
Enn Lust
Institute of Chemistry, University of Tartu, Ravila 14a, 50411 Tartu, Estonia
Summary: Virucidal filter materials were prepared by electrospinning a solution of 28 wt % poly(vinylidene difluoride) in N,N-dimethylacetamide without and with the addition of 0.25 wt %, 0.75 wt %, 2.0 wt %, or 3.5 wt % Cu(NO3)2 · 2.5H2O as virucidal agent. The fabricated materials had a uniform and defect free fibrous structure and even distribution of copper nanoclusters. X-ray diffraction analysis showed that during the electrospinning process, Cu(NO3)2 · 2.5H2O changed into Cu2(NO3)(OH)3. Electrospun filter materials obtained by electrospinning were essentially macroporous. Smaller pores of copper nanoclusters containing materials resulted in higher particle filtration than those without copper nanoclusters. Electrospun filter material fabricated with the addition of 2.0 wt % and 3.5 wt % of Cu(NO3)2 · 2.5H2O in a spinning solution showed significant virucidal activity, and there was 2.5 ± 0.35 and 3.2 ± 0.30 logarithmic reduction in the concentration of infectious SARS-CoV-2 within 12 h, respectively. The electrospun filter materials were stable as they retained virucidal activity for three months.
