The
eluent was filtered through gauze and then dispensed into clean
centrifuge tubes and centrifuged at 2000·g for 30 min. The
supernatant was discarded into disinfectant jar, and the pellet
was washed of Tween 80 by centrifugation (2000·g for 30 min)
with sterile phosphate-buffered saline in the standard procedure
described by Gaspard and Schwartzbrod