AIM AND METHODOLOGY: The aim of this study was to validate the virus removal properties of nanocellulose based filter paper. The filter paper was characterized with atomic force microscopy (AFM), nitrogen gas adsorption and scanning electron microscopy (SEM).Polystyrene latex beads (100nm), gold nanoparticles (50 nm), and murine leukemia virus (MuLV) spiked solutions were used as models.

AFM IMAGE: The filter paper consists of 20-­‐30 nm cellulose nanofibers bundles which form an open 3D porous structure.

GAS ADSORPTION: Most of the pores are 20 nm in size, and no pores larger than 40 nm could be detected.

VISUAL OBSERVATION: A precipitate was clearly seen following the filtration of gold nanoparticles, and the originally red solution of gold nanoparticles turned completely colorless.

SEM: Polystyrne latex beads (100 nm)and gold nanoparticles (50 nm) were efficiently retained on the nanocellulose based filter paper.

MuLV RETENTION TEST: LRV ≥ 5 was observed after filtration as limited by the virus titre in the feed solution and the lower detection limit of TCID50 method.

CONCLUSION: Nanocellulose based filter paper is highly promising for developing a new line of virus removal filters for biotechnological applications, comparable to the state of the art membrane materials.