CHARACTERIZATION OF PURIFIED MS2 BACTERIOPHAGE BY THE PHYSICAL COUNTING METHODOLOGY USED IN THE INTEGRATED VIRUS DETECTION SYSTEM (IVDS)

A new physically based methodology-the integrated virus detection system (IVDS)-was used to characterize a high-concentration, 10.2 mg protein/ mL, sample preparation of MS2 bacteriophage with a reported 10 14 plaque-forming units (pfu)/mL (DPM14) virus count in a common TNME buffer. Virus counts were made using the IVDS instrument following serial dilution. Results indicated virus counts of 1.5 × 10 5 for the neat sample (DPM14), followed by 6.5 × 10 4 viruses (DPM13),1.2 × 10 4 viruses (DPM12),9.3 × 10 2 viruses (DPM11), 88 viruses (DPM10), and 5 viruses (DPM9), respectively. Lower concentrations displayed a consistent multiplier and were consistent with target dilutions. Increases in virus concentration appear to decrease the multiplier, probably through aggregation. The results demonstrate a consistent and simple-to-use methodology. The results further indicate that the IVDS instrument can be used for characterization of other virus preparations with equal ease and similar results.