Table 1.

Efficiency of ultrafiltration method in eliminating severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) from infected cell culture supernatants.

Amicon® Ultra Centrifugal Filter MWCO	PFU/mL in Test Sample	PFU (min–max)/mL in Filtrate
30 kDa	5 × 105	8–12
10 kDa	5 × 105	3–7
5 kDa	5 × 105	0–3
3 kDa	5 × 105	Undetectable

MWCO-Molecular Weight Cut-Off; kDa-kilo Dalton; PFU-Plaque Forming Units. The experiments were done in triplicates using at least two independent biological samples.