1. Research project objectives/ Research hypothesis
The current research project aims to:
a. study the physical mechanisms of nucleation and growth of carbonate apatite and struvite;
b. search substances which would be able to inhibit the nucleation and/or growth of carbonate apatite and struvite in the absence and presence of bacteria;
c. explore whether the mechanism of the aggregation of components of infectious urinary Stones (struvite crystals and amorphous carbonate apatite) can be explained on the basis of the double electric layer (DEL);
d. examine the dielectric properties of struvite crystals which can have an influence on the interaction between bacteria and solid phases existing in the solution of urine.
2. Research project methodology
The first phase of planned research project focuses on the experimental series perform to determine an influence of chosen chemical compounds on the nucleation and growth of carbonate apatite and struvite under condition emulating the infection in urinary tract. The experimental series will be carried out in the environment of artificial urine, and the activity of the bacteria will be simulated by the addition of appropriate chemical substances. Research methods include spectrophotometrical measurements supplemented by microscopic observations. Further investigations will be performed in the presence of appropriate bacteria. This will make possible the determination of the influence of examined compounds on the nucleation and growth of carbonate apatite and struvite as well as on the bacterium viability and activity of urease which is a bacterially produced enzyme.
The second phase of research project aims to perform the measurement of zeta potential using the device Zetasizer (Malvern Instruments), on carbonate apatite, struvite, bacteria and their components such as lipopolysaccharides. The study will be carried out in the environment of artificial urine which the chemical constitution and parameters such as the content of mineral components, pH, density or transparency and the colour are identical with the natural urine of the healthy man. During the studies the strain of Proteus mirabilis isolated from human urinary stone belonging to the collection of clinical strains of bacteria of Department of Immunobiology of Bacteria, University of Lodz will be used. This kind of bacteria is isolated from urinary stones most often. The choice of the species of microorganisms was consulted with medical community. We hope that the results will permit to answer a question, whether the presence of the bacteria influence on the value of the zeta potential and whether the mechanism of the aggregation of components of infectious urinary stones may be explained based on the double electric layer (DEL).
The third part of research project includes the investigations of the dielectric properties of struvite. This phase of research will begin the stage during which the efforts will be undertaken to growth struvite crystals from gel. This method makes possible to obtain crystals about considerable sizes (approximately 1 cm). Such a size is essential to determine the dielectric properties of struvite. These properties can have an influence on the interaction between bacteria and solid phases, and consequently on the intensity and the efficiency of aggregation processes of the examined crystals.
3. Expected impact of the research project on the development of science, civilization and society
The performed experimental series and their analysis should deliver the basis to formulate more complete model of the nucleation, growth and aggregation of chosen components of infectious urinary stones. Successful solution of the purposes of research project gives hopes to formulate new methods of slowing down or prevention the growth of components of infectious urinary stones. Successful solution of given problems can help to undertake the suitable treatment or diet, and consequently can be helpful in liquidating of reasons of the disease, and not only its results. It is worth to emphasize the fact that the current project exemplifies interdisciplinary research. The project includes not only problems from physics of crystal growth, but also the microbiology, chemistry and medicine. The investigations proposed herein are the continuation of research begun during the realization of the previous research project No. N N202 033437. The final report of this project procured acceptance of the Experts Group from the National Centre of Science in respect of the financial and scientific settlement. The results obtained there presume the formulation of the further exploratory way within the framework of this field of research.