Disease diagnosis with invisible light tells a story of water
How did we learn about water? I have graduated from Automation Department of Rouse Technical University in Bulgaria and wanted to become a scientist. Since than, biological systems have captured my attention as being difficult to control and predict. Information is of crucial importance for automated control. Therefore, sensors development became my life work. Luckily, I did my PhD in engineering with Prof. Nicolai Ivanovich Kirilin, one of the few professors in Moscow, Russia, working in the area of Near Infrared Spectroscopy at that time. We were able to develop algorithm and sensor for mammary gland inflammation (mastitis) diagnosis just by analyzing near infrared spectra of cow’s milk.
Near infrared (NIR) light is invisible, but penetrates very deep into the tissue. It is located between visible and infrared light in the electromagnetic spectrum and even millimeters thick biological samples like milk, urine and blood are transparent for it. Unlike the visible (which is reflected by water) and infrared light (which is absorbed by water), NIR light is only slightly absorbed by water. The remaining part of NIR light that has not been absorbed has a unique pattern, which can describe the peculiarities of water and the rest of the molecules surrounded by water as a system.
When I defended my PhD thesis, I was asked why the spectra of NIR light were so informative. That was a tough question for an engineer, but I still try to find the correct answer. It brought me to Japan as a post doc at the Department of Animal Husbandry, Obihiro University where I wanted to learn more about cows and mastitis diagnosis. Later, I decided to do a second PhD in agriculture, at Hokkaido University where, for the first time, non-destructive spectral monitoring of individual cow’s milk was performed for a whole lactation, on a few cows. This opened a new venue of non-invasive biological monitoring as a tool for diagnosis and understanding the disease.
In 1996, I came to work as associate professor of Kobe University and was able to continue my research in the same area of non-invasive diagnosis. Since 2006, we established a new Laboratory on Biomeasurement technology at the Faculty of Agriculture. Analyzing NIR spectra of various biological systems real time and in-vivo, from DNA, cells, bacteria, plants to animal tissue, bio fluids and just aqueous solutions brought the finding that water molecules arrangements, i.e. bonding, seen with the NIR light, might be related to the definition of various physiological conditions including “diseased” one, too. We proposed a new scientific area called Aquaphotomics as a new member in the “omics” area devoted to examine “all about the interaction between water and light” and present spectroscopy as an important tool to study the functionality of water in Life science.
Our goal is to understand how other molecules and environment perturb the water matrix through creating a database of newly founded water absorbance bands. Now, we are working on finding characteristic water absorbance patterns related to various systems and diseases. We expect to show that there is a common base for different diseases and it is called “water absorbance pattern”.