title: Sizes and concentrations of several type C oncornaviruses and bacteriophage T2 by the resistive-pulse technique.
abstract: Viruses above about 60 nm in diameter may be rapidly sized to a few nanometers in their natural hydrated state as they pass one by one through a single pore in a newly developed nanometer-particle analyzer based on the resistive-pulse technique of the Coulter Counter and the use of submicron diameter pores made by the Nuclepore process. Size measurements for several type C oncornaviruses are: Rauscher murine leukemia, 122.3 +/- 2 nm; simian sarcoma, 109.7 +/- 3 nm; Mason-Pfizer monkey, 140.0 +/- 2.5 nm; RD-114, 115 +/- 5 nm; and feline leukemia, 127.4 +/- 2 nm, relative to standard 109-nm latex spheres. The T2 bacteriophage has a volume of (5.10 +/- 0.15) X 10(-16) cm3. Concentrations of viruses near 10(9) to 10(11)/ml that are fairly clear of debris are routinely measurable in a few minutes to an accuracy near 15%. A lower practical count limit is near 5 X 10(7) viruses per ml.
mesh_terms: D003090:Coliphages / Q000302:isolation & purification; D007840:Latex; D005256:Leukemia Virus, Feline / Q000302:isolation & purification; D008851:Micropore Filters; D008863:Microspheres; D009858:Oncogenic Viruses / Q000302:isolation & purification; D010316:Particle Size; D011925:Rauscher Virus / Q000302:isolation & purification; D012190:Retroviridae / Q000302:isolation & purification
chemical_list: D007840:Latex