Mille-feuille paper: a novel type of filter architecture for advanced virus separation applications

Abstract

Mille-feuille (''a thousand leaves'') paper is the first non-woven, wet-laid filter paper, composed of 100% native cellulose, which is capable of removal of the ''worst-case'' model virus, the non-enveloped parvoviruses, i.e. minute virus of mice (MVM; 18-20 nm), from water with a log 10 reduction value (LRV) >5 (>99.999%). We further illustrate how the flow rate across the mille-feuille paper can be increased exponentially so that flux rates in the order of 350 L m À2 h À1 bar À1 can be potentially achieved.

High‐Performance Virus Removal Filter Paper for Drinking Water Purification

“…This nonwoven filter paper, made from 100% cellulose nanofibers, features a stratified internal architecture, consisting of numerous cellulose nanofiber sheets—hence, its name is “mille‐feuille” (or thousand leaves) filter paper. The separation efficiency of the mille‐feuille filter was verified for surrogate nanoparticles, e.g., gold nanoparticles or fluorophore‐labeled latex nanobeads, and real viruses, e.g., influenza virus, i.e., swine influenza A virus (100 nm); retrovirus, i.e., murine leukemia virus (100 nm); and parvovirus, i.e., minute virus of mice (20 nm) . In this article, the properties of the mille‐feuille filter paper are evaluated for water treatment applications for the first time.…”

“…The resulting pore‐size distributions from nitrogen sorption measurements of the nanocellulose filter papers of thicknesses 9 and 29 µm are presented in Figure . A shift in the pore‐size distribution toward pores of a greater width was observed for the thinner filter papers, consistent with previous observations …”

“…In particular, the 29 µm filter paper at 3 bar exhibits steady LRV ≥ 5 and V max ≈ (1.8 ± 0.1) × 10 3 L m −2 , measured with spiked 30 nm latex nanoparticles in SWW, whereas for 9 µm filter paper at 1 bar the observed virus LRV gradually decreases from 3.5 to 2.2 and V max is around (9.7 ± 4.6) × 10 2 L m −2 , under similar experimental conditions. The latter difference could potentially be due to compaction of the 29 µm filter paper at 3 bar as discussed earlier . It should be noted that the 9 µm filter exhibits higher variability of V max values, which is likely to be due to larger spread of initial flux values and extrapolation.…”

“…The advances in nanocellulose science allow today for cost‐efficient production of this material . Recently, a highly cost‐efficient virus removal filter paper, aka mille‐feuille filter paper, was described for applications in biotechnology . It is produced by traditional paper‐making processing, which contrasts starkly from the membrane technology relying on phase inversion.…”

Sulfonated nanocellulose beads as potential immunosorbents

“…It is obtained from filamentous green algae that can be harvested at various coastal areas around the world (Mihranyan et al 2007). The unique features described above have contributed to the increasing interest in using Cladophora nanocellulose in biomedical applications such as in hemodialysis membranes, (Ferraz et al 2012(Ferraz et al , 2013Ferraz and Mihranyan 2014) for electrochemically controlled DNA extraction, (Razaq et al 2011) DNA-immobilized immunosorbent membranes, (Xu et al 2016) for adsorption of metals from solution and for size-exclusion virus removal (Metreveli et al 2014;Asper et al 2015;Gustafsson et al 2016).…”