A few months back a 5th annual conference “Physics of aqueous solutions” has been concluded . Over the duration of three days more than 100 scientists from 7 countries have presented their works on novel and unusual properties of water and water-based solutions. The conference had a large amount of interesting works and some lively discussions filled with questions. The interest manifested towards aqueous solutions was palpable in the audience hall.
The conference consisted of 5 large distinct sections:
- Study of external action on aqueous solutions
- Models structure and chemical kinetics of aqueous solutions
- Aqueous solutions in materials science
- Aqueous solutions in biological systems
- Methods for study of aqueous solutions
Some of the most interesting studies presented during the conference concerned using novel ways of diagnostics using physical and chemical properties of water. For example, Roumiana Tsenkova from Kobe University, Japan reported a way of both measuring and visually representing (figure below) infrared spectra observed by special cameras. This non-invasive technique is based on the fact that water can have distinct infrared absorption patterns correlating to dissolved substances and state of water (for example, it can be bound within molecules or supramolecular complexes). Using this technique, Roumiana and her colleagues were able to detect a large array of processes in motion, ranging from biological pathologies to cement drying . Scientist has an entire book published dedicated to bio diagnostics of dairy products.
Another interesting example of novel diagnostics was presented by Alexander Shkurinov. It was previously known that water can absorb not only infrared electromagnetic radiation, but THz as well. THz radiation has longer wavelengths and can penetrate a few centimeters of semitransparent materials (like our skin). However, only recent advances in THz camera miniaturization have made visualization using those cameras viable. Just like infrared waves mentioned before, radiation with longer wavelengths is absorbed differently by water in different states. Therefore, using the THz cameras, it is possible to study the condition of someone’s skin, health of their eyes or even detect brewing anger (presented in the figure below).
The theme of ultrahigh dilutions was heavily present in all of the sections. However, they were most prevalent in the first section, that viewed serial dilution as another version of external action that could influence water properties.
One such study by Maxim Astashev was concerned with relationship between serial mechanical action and spontaneous chemiluminescence of protein solutions. The study shows that after undergoing specific vibrational conditioning aqueous solutions of BSA (either in high or UHD concentration) show changes in their properties. Namely, number of photons detected as spontaneously released from the solution can change (either increasing or decreasing, depending on the nature of specific vibrational action).
Another example of ultrahigh dilutions having unexpected physical properties was presented in the review by German Stepanov. According to the scientist, solutions of different substances can not only absorb infrared light differently (as discussed earlier) but also show signs of active infrared radiation , which can in turn influence other biological systems. Review presented data that shows that IFNg dilutions can change neutrophils behavior, supposedly through infrared radiation.
Section concerning interaction of aqueous solutions with biological systems has many interesting cases of small distinctive features of water interacting with different biological molecules. Quite a few reports had intersecting topics: DNA, water chirality, using additives of salts to qualitatively change the behaviour of other molecules in solutions.
For example, a report by Nikita Penkov was dedicated to detecting DNA hydrate shells as well as changes observed when adding different salts to DNA solutions. The aforementioned THZ spectroscopy was used to detect these hydration processes. Water molecules within DNA grooves were observed to have heavily structured behaviour (as to be expected), while a few layers of outer molecules were also observed. Potassium ions were shown to disrupt the hydrate shells, while magnesium changed the orientation of water molecules. These results conform to previously known data and show that THZ can be confidently used as a method to study water structures.
Other sections have just as much interesting material. For example, the section dedicated to models has a few possible explanations of unusual water behaviour. The section about materials science has examples of aqueous solution changing technological characteristics of cement and even gasoline. However, discussing all the results that were presented in the conference lays beyond the purview of this article.
Overall, the conference shed light on a lot of different novel qualities of aqueous solutions. And despite relatively recent advances in this scientific sphere, quite a few products using these qualities already exist in commercially available forms. For example, drugs based upon ultrahigh dilutions of specific antibodies and using unique biophysical properties of these aqueous solutions are available worldwide. One can safely assume that with years the number of such conferences and their significance will only increase.