STUDIES IN ULTRAFILTRATION.

Area of Science:

• Virology
• Biochemistry
• Filtration Science

Background:

• Accurate size determination of viruses and bacteriophages is crucial for understanding their nature and behavior.
• Previous methods for size estimation had limitations, necessitating the exploration of new techniques.
• Enzymes like trypsin and proteins such as casein serve as important size references in biological studies.

Purpose of the Study:

• To estimate the relative sizes of bacteriophages and viruses using ultrafiltration.
• To compare the sizes of bacteriophages and viruses with known proteins and colloidal particles.
• To evaluate the potential of ultrafiltration as a standardized method for size determination in microbiology.

Main Methods:

• Utilized ultrafiltration through collodion membranes with controlled pore sizes.
• Filtered various substances including crystallized egg albumen, serum albumen, casein, trypsin, bacteriophage, Rous sarcoma virus, and herpes virus.
• Compared filtration results with colloidal arsenic trisulfide and collargol as size standards.

Main Results:

• Bacteriophage, Rous sarcoma virus, and herpes virus were found to be larger than casein and collargol but smaller than colloidal arsenic trisulfide.
• Estimated sizes for these biological agents ranged between 20 and 100 millimicrons, aligning with previous studies.
• Herpes virus filtration was challenging, likely due to its association with brain material, suggesting an intracellular location.

Conclusions:

• Ultrafiltration provides a viable method for estimating the size of viruses and bacteriophages.
• The findings support the classification of bacteriophages and certain viruses as distinct entities comparable in size.
• The developed ultrafiltration technique shows promise for standardization in investigating bacteriological and immunological problems.