Gerald H. Pollack, PhD

Professor of Bioengineering - Box 355061

University of Washington

Seattle, WA 98195

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Research Themes

The Pollack laboratory centers largely on the identification of water’s fourth phase, otherwise known as exclusion-zone water. EZ water has many applications in nature and technology. Among the natural applications, the lab lays special emphasis on the role of EZ water in health, including cell biology. There is also an historical emphasis on biological motion and the origin of life. Further, several technologies have emerged from the fundamental discoveries made in the laboratory, and a spinoff company called 4th-Phase, Inc., has been formed to pursue those technologies.

Below you will find summaries of the major themes of the Lab. 


EZ Water:  Water has three phases – gas, liquid, and solid; but findings from our laboratory imply the presence of a surprisingly extensive fourth phase that occurs at interfaces. The formal name for this fourth phase is exclusion-zone water, aka EZ water. This finding may have profound implication for chemistry, physics, and biology.

The impact of surfaces on the contiguous aqueous phase is generally thought to extend no more than a few water-molecule layers. We find, however, that colloidal and molecular solutes are profoundly excluded from the vicinity of hydrophilic surfaces, to distances up to several hundred micrometers. Such large zones of exclusion have been observed next to many different hydrophilic surfaces, and many diverse solutes are excluded. Hence, the exclusion phenomenon appears to be quite general.​

To test whether the physical properties of the exclusion zone differ from those of bulk water, multiple methods have been applied. NMR, infrared, and birefringence imaging, as well as measurements of electrical potential, viscosity, and UV-VIS and infrared-absorption spectra, collectively reveal that the solute-free zone is a physically distinct, ordered phase of water. It is much like a liquid crystal. It can co-exist essentially indefinitely with the contiguous solute-containing phase. Indeed, this unexpectedly extensive zone may be a candidate for the long-postulated “fourth phase” of water considered by earlier scientists.

The energy responsible for building this charged, low entropy zone comes from light. We found that incident radiant energy including UV, visible, and near-infrared wavelengths induce exclusion-zone growth in a spectrally sensitive manner. IR is particularly effective. Five-minute exposure to radiation at 3.1 µm (corresponding to OH stretch) causes an exclusion-zone-width increase of up to three times. Apparently, incident photons cause some change in bulk water that predisposes constituent molecules to reorganize and build the charged, ordered exclusion zone. How this occurs is under study.

Photons from ordinary sunlight, then, may have an unexpectedly powerful effect that goes beyond mere heating. It may be that solar energy builds order and separates charge between the near-surface exclusion zone and the bulk water beyond — the separation effectively creating a battery. This light-induced charge separation resembles the first step of photosynthesis. Indeed, this light-induced action would seem relevant not only for photosynthetic processes, but also for all realms of nature involving water and interfaces.

The work outlined above was selected in the first cohort of NIH Transformative R01 awards, which allowed deeper and broader exploration. It was also selected as recipient the 2008 University of Washington Annual Lectureship. Each year, out of the University’s 3,800 faculty members, one is chosen to receive this award. Viewable here, the lecture presents the material in a lively manner, accessible to non-experts.


The material now appears in a book, published 2013, entitled The Fourth Phase of Water: Beyond Solid, Liquid and Vapor. Sample chapters are freely accessible at, which also contains published reviews. Reader reviews can be found on


Many lectures and interviews on the material above can be found on the internet. Of interest are two TEDx talks. The original one presents an outline of the basic discoveries, designed for a lay audience. The second one, 2016, describes the relevance of EZ water for health.


Also of interest may be a short Discovery Channel piece that combines fourth phase water with snowboarding.


Water Based Technologies: Out of the findings described above, and published in a recent book, fresh opportunities have arisen for addressing pressing societal needs for scarce drinking water and renewable energy. We have therefore started a spinoff company, 4th-Phase, Inc., to develop these technologies.

Here are three examples:

Filterless filter

Exclusion-zone separates solutes from water, in the absence of any physical filter.

The discovery of large solute-exclusion zones next to hyrdrophilic surfaces implies that solute-free and solute-containing water can be separated naturally, without need for physical filters. The required energy comes from incident light. The solute-exclusion zones are macroscopic; hence, collection is feasible through simple processes.

Proof-of-principle has been demonstrated: model contaminants could be separated to a ratio up to 200:1 in a single pass (Klyuzhin et al., 2008). With successful demonstration, efforts are underway to scale up the process and collect solute-free, particle-free, and pathogen-free water in a simple, economically feasible way.


It appears that various salts are excluded from EZ water. Hence, efforts are underway to exploit the technologies above to desalinate water.

Energy from Water and Light

Separation of charge allows for the drawing of electrical energy from the water-based battery.

We found that the solute-exclusion zone is charged, while the zone beyond is oppositely charged. This separation constitutes a battery, from which current can be drawn. The battery is re-charged by incident radiant energy. Hence, the process resembles the first step of photosynthesis in that incident light yields charge-separation and useful energy. It is effectively a photoelectric effect, except that the medium is ordered water.


Experiments are underway to explore the phenomenon of charge separation in water. The scientific underpinning of this separation is extremely interesting, and is revealing as much about the structure, chemistry, and physics of water as about the prospects of obtaining clean electrical energy from water.


Water and Health:  We are studying the central role of water in health. We are two-thirds water -- by volume. In terms of the percentage of molecules, that two-thirds figure computes to a lot of water molecules: more than 99% of our molecules are water molecules. Evidence suggests that those 99% don't merely sit as the background carriers of the more important molecules of life, but are central participants. All that the cell does depends on water.

That leads to the hypothesis that proper hydration is a central feature of function, and therefore of health.

Considerable evidence supports that point of view.  Informal discussion of the evidence for the role of water in health appears in an interview with Dr. Mercola. And, a recent lecture dealing with EZ water and health is found here. And, a grant proposal  submitted earlier to the NIH contains a more formal discussion of the evidence.

We are actively seeking funding to carry out a comprehensive study on the role of water in health. The public seems hungry for this kind of information. With our background in water chemistry and biology, we feel we're well equipped to carry out those studies.

Who knows? EZ water may become the next wonder drug.


Water and Cell Biology:  Contemporary views of cell biology consider water merely as a background carrier of the more important molecules of life. However, water may be a central player in life processes.

Surface charge on the internalized bacterial cell organizes host cell water and extends host cell proteins.

Pioneers such as Albert Szent-Gyorgyi, who won the Nobel Prize for discovering vitamin C and is commonly regarded as the father of modern biochemistry, knew that water’s role in biology was central. Szent-Gyorgyi’s sentiment is expressed in the following quote: “Life is water dancing to the tune of solids.” The huge literature built around the centrality of water by Gilbert Ling and others has been largely forgotten with current reductionist approaches that emphasize slice-and-dice rather than on more holistic approaches. Some believe that modern biochemistry and cell biology have missed the boat by ignoring the centrality of life’s most abundant constituent: water.

The book, Cells, Gels and the Engines of Life builds on the central role of water for biology. It provides evidence that much of the water in the cell is very near to one or another hydrophilic surface and therefore ordered, and that cell behavior can be properly understood only if this feature is properly taken into account. The book goes on to show that seemingly complex behaviors of the cell can be understood in simple terms once a proper understanding of water and surfaces is achieved.


The more recent book, The Fourth Phase of Water, expands on the theme of ordered water, detailing its structure and building implications for nature and technology.


Information in Water: When reports of information storage in water surfaced in the late `80s, world reaction was skeptical. This seemed impossible. Water molecules are known to jiggle around randomly at a furious pace; there seemed no possible substrate for long-term memory.

That changed with the advent of EZ water. The structural lattice is essentially fixed. Oxygen and hydrogen atoms lodge at fixed positions within the lattice, and if any one of those atoms could get modified, that would constitute information. Modification possibilities abound: oxygen atoms have five possible oxidation states: -2, -1, 0, +1, +2. Hence the potential for high-density information storage is extraordinary.

Many experiments from various laboratories have reported information storage in water. We are actively pursuing that line of investigation to identify possible ways in which information can be input, stored, and read out of, water. This could be critically important. EZ water could constitute the future of high-capacity computer memory. And, EZ water-based information could be critical for health.


Biological Motion:  Up to the current millenium, biological motion had been the mainstay of this laboratory, the focus having been mainly on muscle contraction. The laboratory is known for building front-line instrumentation such as precision optical detectors and nanolevers for sub-nanometer length measurements, and for its penetrating tests of prevailing molecular theories. The award-winning 1990 book, Muscles and Molecules: Uncovering the Principles of Biological Motion ( outlines reasons why the prevailing lever-arm hypothesis is fundamentally inconsistent with available evidence, and goes on to suggest an alternative.

illustration depicting the essential structure of a skeletal muscle cell

Although muscle contraction per se is no longer the main emphasis of this laboratory, still, the considerations brought forth in that book and elaborated in the newer book, Cells, Gels and the Engines of Life, remain relevant. They suggest that the hypothesis of the lever-arm-based mechanical “motor” is fundamentally inadequate and that mechanisms based on protein-water phase transitions are both simpler and at least as consistent with available evidence.

Studies of biological motion have more recently focused on water-based mechanisms. We have observed molecular and particle motions driven by charge-driven water flows. These flows appear to be driven by the surface-ordering phenomena described above, and seem likely to be centrally involved in biological motions. We are pursuing them actively.


Origin of Life:  Fresh evidence provides new clues for solving the mystery of how life began.

Like-charged particles or molecules attract one another because of an intermediate of opposite charges. The opposite charges arise directly from exclusion-zone formation.

In exploring life’s origin, one conundrum has been the issue of how scattered molecules coalesce to form a condensed mass. Recent experimental results imply a potentially simple solution to this conundrum. In aqueous media, it has been long known that like-charged substances do not necessarily repel one another; they actually attract one another. Feynman referred to this paradoxical attraction as “like-likes-like” and went on to postulate that the attraction occurs because of the “unlikes” that inevitably gather in between, thereby creating the attractive force.

Feynman’s thesis has been supported by elegant experiments of Norio Ise at Kyoto University and we have been able to confirm this thesis with direct evidence (Nagornyak et al., 2009). We found that like-charged gel spheres immersed in water and separated by as much as half a millimeter attract one another; they attract despite the large separation, and after some time they coalesce. Further, we confirmed the expected presence of opposite charges lying in between the spheres. The opposite charges derived from the exclusion-zone that develops around each sphere, generating opposite charges beyond, and in high concentration in between the spheres. Thus, it is true that like-likes-like through an intermediate of unlikes, as Feynman theorized.

Hence, we now understand why like-charged entities attract in aqueous solution. The energy mediating the attraction comes from radiant sources, which build exclusion zones and separate charge. The attraction is therefore energy consuming, although the energy is freely available from the environment.

The upshot is that a mechanism for building condensed masses is now experimentally verified. In order for this mechanism to work, all that is needed is water, light, and molecules/particles. Even if those entities bear the same charge, they will self-assemble into a condensed mass. This process is presumably the first step in producing the condensed mass that ultimately became the cell. It is sufficiently simple that one wonders whether life is being produced this very day (Pollack et al., 2009).