The purpose of this post is to describe the interaction of electric and magnetic fields with intracellular “structured” water. Structured water refers to when water reorientates and forms transient patterns after coming into contact with electric fields from charged surfaces or molecules, such as biological membranes (2D), biological fibres (1D) or ions (point).
Note: the term “structure” in this context is not meant to mean homeopathic water “memory” and there is no hypothesis that water can store information within its structure. The hypothesis in this post is that the electric and magnetic fields interact with water in order change its orientation to affect the behaviour of other fields.
The purpose of this post is to examine the experimental evidence of the permeability (dielectric constant) of water at the interface, for theoretical models and how close they fit the evidence
It is more than a coincidence evidence of structured water around charged surfaces and molecules in cells is as anomalous as water itself. The instability of water in different contexts provides an opportunity for evolution to exploit its properties.
The Classic Electric Double Layer.
Helmholtz (1853) was first to have the idea that when water came into contact with a charged surface it would form an layer of oriented water molecules. The idea was that a negative surface would attract the positive hydrogen atoms and a positive surface would attract the negative oxygen atoms. This would result in what has been called a “double layer” or “Helmholtz layer”.
Diagram from (Gongadze 2009) showing the Helmholtz double layer.
Later Gouy (1910) and Chapman (1913) developed a diffuse double later where the first later was not a definite but a probability,
Diagram from (Gongadze 2009) showing the Gouy-Chapman double layer.
model.
Later still Stern (1924) developed a double layer model, that combined he previous models, with the first layer like the Helmholz and then a region of diffuse charged molecules.
Diagram from (Gongadze 2009) showing the Stern double layer.
model.
The classical models give an idea of interaction of charged surfaces with water. However, none of these “classical” models fit the experimental data perfectly due to “ion-ion correlations, electrostatic image interactions, steric effects, overlapping of ions leading to inconsistency with the experimental results.” (Gongadze 2009).
Predictions of the behaviour of more recent water models, such as TIP4Q (Alejandre 2011) and SPC/ε (Fuentes-Azcatl) are shown below.
Permeability (ε) and Permittivity (µ)
Classical electromagnetic properties of water are permeability and permittivity. As was converted in more detail in the previous post. Permeability (ε) is the measure of a material to support the transmission of electric fields. Permittivity (µ) is the measure of a material to support the transmission of magnetic fields.
The experimental evidence of the permeability (dielectric constant) of water at a charged interface shows that it falls dramatically near a charged surface. Meneses (2018) found the permeability of water was 55ε at 37ºC (310K) in a layer of water next to a surface of sodium dodecyl sulfonate, a surface often used as a control in experiments. This compared to 75ε in bulk water.
As has been stated above, many theoretical water models fail to match up to experimental data at room temperatures. Meneses (2018) found the recent theoretical models that better fitted experiment data were TIP4Q (Alejandre 2011) and the SPC/ε (Fuentes-Azcatl).
Diagram from Meneses (2018) showing the fit of two theoretical models of water TIP4Q and SPC/ε. The red line shows the experimental dielectric constant of bulk water. The black line shows the models prediction. The green dot shows the experimental data at the surface.
The models so far have assumed a single layer of oriented water molecules. However the oriented charges of the initial layer of water molecules could form a charged surface that would attract other water molecules, creating multiple layers.
A multi layered model (Tanizaki 2002) on a biological membrane found a much lower dielectric constant of 2 and 7 close to the surface of a 3 layered water model and a a higher dielectric further away.
Diagram In a model with more layers. The scale is in Å (tenth of a nm). In the model with five dielectric layers the dielectric constant increased to over 200 (Tanizaki 2002).
Other models have also found the dialectic constant falls to 2 at the surface .
Diagram from Fumagalli (2018) who also found that the dielectric constant (ε) is only ~ 2 in a layer 2-3 molecules thick (1.4nm) and 4.4ε at 3.8nm and 15ε at 10nm.
Diagram from Gavish (2016) showing the dielectric constant a number of Å away from the surface. With the dielectric constant of the three water molecules nearest the surface being 2.1ε – 2.4ε and rapidly rising to 80 in the bulk water.
Ions
More recent models also include ions which are attracted to the surface of the charged water particles, forming a layer of ions (Brown 2016).
Diagram showing layer with an additional layer of ions (Brown 2016)
Graph (brown 2016) showing how the concentration of different salts forms an additional layer at different distances from the surface. The prediction is that the larger hydrated cation radius the further away from the surface the layer would form. Because Ca+2 has a larger hydration radius it would be predicted that the calcium cations will form a layer further than one Å.
In solution ions separate. Gavish (2016) found with 1mM of salt there is 12nm distance between ions, which involves 50-100 water molecules screening each ion. At 1000mM concentration ions are 1.2 nM apart, and three water molecules separate each ion.
Gavish (2016) found that the higher concentration of salts in bulk water reduced the dielectric constant by more than 50%.
Diagram from Gavish (2016) showing reduction of dielectric constant with an increase in salts.
The diffusion of ions in bulk water differs. Protons (H+) and calcium (Ca+2) is approximately 5-10 slower compared with sodium (Na+2) and potassium (K+2) in the intracellular water (Stuart 2016).
Ion Channels
Ions channels (and connexions) act as the main point of entry and exit into intracellular water. When ions pass though the membrane they face a dielectric layer to pass through. Ions are kicked out of ion channels by preceding ions by Coulomb repulsion.
Cherepanov (2003) found that the low dielectric permittivity against the membrane surface created a barrier of 0.1–0.15 eV for cations entering the cell.
Diagram showing the electric barrier at different distances faced by cation entering the cell. With a maximum at 0.5 nm from the surface (Cherepanov 2003). Once a proton (hydrogen cation. H+) entered the cells its movement along the surface was fast, with a distance of 1mm being covered in 100 ms.
Proton (H+) channels mostly exist in pairs or clusters. When protons are ejected into the cell they are spread quickly along the inner surface, and can escape into bulk water Cherepanov (2003). Calcium channels would also produced elevated concentrations of calcium ions close to the pump exits.
Diagram showing the distribution of protons on the membrane surface around a proton channel.
Blaaka (2003) also found the dielectric permittivity in a spherical cavity increasing from 2 to 80 over 5nm from the boundary to the bulk water in the centre. This layer barrier acted a barrier for proton (H+) pumps, leading to a build up of protons at the boundary.
Ions diffuse into the cellular water at different rates. Data shows that hydrogen (H+) and calcium (Ca+2) ions diffuse at a lower rate than sodium (Na+) and potassium (K+) ions. Hydrogen and Calcium ions are also absorbed by buffers slowing their diffusion down.
| Ion | Extracellular | Intracellular (um2/ms) |
| H+ | 8 | 0.1-0.2 (buffered) |
| Na+ | 1.9 | 1.15 |
| K+ | 1.96 | 1.3-1.73 |
| Cl- 2 | 2 | 2 |
| Ca+2 | 0.6 | 0.223 (free) 0.01-0.05 (buffered) |
Table showing diffusion rates of ions in extracellular and intracellular water (Stuart 2016
Waveguides
It has been calculated that dielectric constant of 80 in bulk water and 2 in the double layer acts like a boundary of a dielectric waveguide. Roozbeh (2013) showed how the double layer reflects electromagnetic waves, as a waveguide.
Neurological Implications
The text book literature often dismisses the role of electric fields in water because the high permeability (dielectric constant) of 80 in bulk water would mean that electric charges would be absorbed (“screened”) very close to their source. However the evidence is that EEG and MEG measurements of oscillating fields show electric and magnetic fields can travel across the brain. A more detailed examination of the evidence shows that permittivity and permeability falls to low levels in intracellualr water near charged surfaces and molecules. The evidence also shows that static electric fields can change the permitivity and permeability of water and that electromagnetic wavelengths of ions have high rates of permeability and permittivity in water.
Importantly, a more complex dielectric function, ε(q,w), describing both the wave-vector-dependent (oscillating static fields) and frequency dependent (electromagnetic fields) gives a more relatistic picture of fields in water. This measures a longitudinal·field which varies in both space and time of a combined wave-vector (wave oscillation) and wave frequency. This can be used to measure the longditudial and transvers behaviour of weak external fields in space and time and the time-dependent collective excitation of waves (density fluctuations) of the electronic “fluid” (plasmon modes). (e.g. Walter 1971, Omelyan 1998, 1999a, 1999b).
The evidence of electric and magnetic fields in water indicates a dynamic environment, where static forces can temporarily change the stucture of water and electromagnetic fields move at different rates with different wavelengths water. This implies cellular water could form a tuneable electromagnetic environment.
The models of structured water show that under different circumstances water can flip between a bulk phase and a structured phase. All these models have in common an assumption that surfaces are homogeneous surfaces and ions are passive. However cellular surfaces are not homogeneous, and the ions are not passive. A theory of unstable disordered organic surfaces has attracted far less attention than interfaces of uniform charged surfaces. (Whitesides 1989).
Fields of Consciousness 