Figure 1
From: Detection of BK virus in urine from renal transplant subjects by mass spectrometry
Centrifugation-based separation and enrichment workflow of urine samples. Urine samples were separated via centrifugation into three fractions: a cellular fraction containing epithelial cells pelleted by centrifugation, an intact virus fraction generated via ultracentrifugation through a 10% sucrose cushion and the ultracentrifugation supernatant was concentrated by a 5 kDa cut off filter to produce a fraction containing released viral material. Proteins from all fractions were methanol / chloroform precipitated and in-solution digestion was carried out followed by LC-MS/MS analysis.