Published Papers

Analysis of the Physical Behavior of Viruses Using the Integrated Virus Detection System (IVDS)
Charles H. Wick
U.S. Army Soldier and Biological Command, Edgewood Chemical and Biological Center
AMSSB-RRT-DT, Aberdeen Proving Ground, MD 21010
A physical approach to virus detection, analysis and identification has been invented and patented at the US
Army SBCCOM. The Integrated Virus Detection System (IVDS) is a reliable, high-speed instrument for
detecting viruses that changes everything in respect to virus analysis. No culturing, no reagents, quick
analysis, generic to all viruses. The current instrument has been used to examine viruses separated from
complex mixed samples with sensitivity to less than 10 viruses at the counter. Other virus characteristics
have been observed and calibrated, e.g. passage of viruses through filter membranes and exceptional
survival in both extreme temperature and pH and virus fate curves for various environmental situations.
This briefing reviews results from several studies and presents an operational review of the instrument.
IVDS is a new invention1-2 that utilizes the physical properties of virus, virus-like and other nanometer
particles to determine a concentration, distribution and information for discrimination and characterization
of nanometer sized viruses3 (1 nm equals one billionth of a meter). Viruses have been measured and
calibrated from 23nm to more than 220 nm using a wide range of viruses4-5. Methods have been developed
to separate viruses from various background material to yield a clean, concentrated virus sample suitable
for analysis6. This analysis has lead to a several new discoveries that includes the observation of some
viruses passing unexpectedly through filters7, to decay easily, and for some to survive intact for long time
under harsh environments including soil, sand and water. Detection can be made for the many known virus
families pathogenic to man. This approach gives a new means for detecting unknown and emerging
viruses8. Another advantage is that since the current IVDS instrument does not require complicated
chemistry or reagents it can be used by nearly anyone. The technology was transferred by exclusive patent
license agreement that includes a large team of scientists and engineers key to the successful technology
transfer to industry.
Other more familiar sounding methods require specialized reagents, skill, and frequently time in making an
analysis, most are very difficult to set up, destroy the sample and have limited application to un-named
1 Patents: Wick, C.H., U.S. Patents 6,051,189, 6,485,686, and 6,491,872, others pending.
2 Wick, C.H,, Quasi-Realtime Monitor for Airborne Viruses, ERDEC-TR-459, January 1998
3 Wick, C.H., McCubbin, P., Characterization of Purified MS2 Bacteriophage by the Physical Counting
Methodology used in the Integrated Virus Detection System (IVDS), Toxicology Methods, 9:245-252,
4 Wick, C.H., McCubbin, P., Characterization of the Integrated Virus Detection system (IVDS) Using MS-2
Bacteriophage, ECBC TR-018, May 1999.
5 Thomas, J,, Bothner, B., Traina, J., Benner, H., Siuzdak, Electrospray ion mobility spectrometry of intact
viruses, Spectroscopy 18 (2004), 31-36.
6 Wick, C.H., McCubbin, P., Removing Complex Growth Media from MS-2 Bacteriophage Cultures,
ECBC-TR- 55, August 1999
7 Wick, C.H., McCubbin, P., Passage of MS2 Bacteriophage Through Various Molecular Weight Filters,
Toxicology Methods, 9:265-273, 1999.
8 Kuzmanovic, D., Elashvili, I., Wick, C., O’Connel, C., and Krueger, S., Dacteriophage MS2: Use of
Small-Angle Neutron Scattering and a Novel Concentration Determination Method to Obtain the Spatial
Distribution and Molecular Weight of the Protein and RNA Components, Structure, Vol. 11, 1339-1348,
November 2003.
The first objective after developing the IVDS instrument was to calibrate it over a wide range of virus
particles. This was accomplished using standard viruses and personnel and material from the National
Institute of Standards and Technology.
The second objective was to demonstrate the effectiveness of IVDS is counting viruses under a wide range
of conditions. This is important as there are many inherent challenges to virus detection and analysis,
among the primary is purification and concentration from the background material. The first demonstration
was the ability to count viruses in filter systems, both in the filtrate and those retained on the filter. The
second demonstration was the ability to separate viruses from complex media, such as growth compounds,
salts, proteins, and mixtures. The third demonstration was the ability to observe viruses as they changed
following exposure to temperature and pH.
Twelve viruses and one empty capsule
form were characterized. Samples were
prepared by ultra-filtration, concentrated,
and counted using the IVDS system.
Standard methods were used for filtration,
heating, and pH demonstrations.
A typical output from IVDS is given in
Figure 1. Virus size and concentration are
given as a graph. Statistical information
is given for the virus such as mean size,
total concentration, and a table of all the
particles in the size range is prepared for
each sample. In this manner the size,
concentration and details of the analysis
are presented. There is enough data in
this chart to make a preliminary
discrimination among samples and
evidence for a preliminary identification.
Results include data that illustrate the ability of
MS2 to pass through 1M Dalton filters with ease,
and to pass through 750K, 500K and 300K filters.
MS2 was retained on 100K Dalton filters. This
was an interesting result for an approximately 3M
Dalton sized virus. The second demonstration
illustrated the successful separation of MS2 from
several proteins, salts, and growth media. The
exposure of MS2 to continuous heat demonstrated
a robust organism that retained structural integrity
for more than 2 hours at 63oC and more than
several minutes at 70oC. MS2 was further
demonstrated to retain integrity for several hours at
pH 1.41 and for several days at pH 10 and pH 11.1.
Other results demonstrate the detection of multiple
viruses in a single one minute sample analysis
(Figure 2).
This briefing will review the results of this research and follow-up by presenting an operational overview
of the IVDS instrument. The immediate impact on Army operations with a device of this type is virus
screening and detection of a wide range of environmental samples.