,,Calorimetric study of calcium nanoparticles’’

The study of the possible interaction between calcium and lipids is of great importance for the studies of complexes of calcium drug carrier nanoparticles. Complex liposomes were created by the new technology developed at the Department of Biophysics. Complex liposomes from DPPC lipids were prepared and their thermodynamic properties were studied. In calorimetric studies, we determined that the phase transition temperature of these complexes is close to 420 C. It was shown that both hydrophobic and hydrophilic connections take part in the formation of calcium nanoparticles. We were interested in hydrophilic bonds represented by hydrogen bonds. We have shown that these hydrogen bonds are formed between the phospholipid heads, and the main contributor is the oxygen atoms present in the phosphate acid residue. In addition, on the basis of the amount of heat absorbed during the breaking of hydrogen bonds formed between complexes of calcium nanoparticles, it can be concluded that the hydrogen atoms in the head of DPPC lipids form hydrogen bonds between P=O and P-O groups of phosphate. The energy of heat absorption measured by the calorimeter is of the order obtained by breaking the hydrogen bonds we have specified. Thus, we conclude that our approach to the model of liposome formation from lipids is correct. As for calcium atoms - due to the fact that it is present in the form of positive ions, it will connect only with negative ions in the liposome.