Experimental and computational study of properties of biological and synthetic macromolecules in solution

In recent years computational and experimental procedures has been developed in order to study and characterize the behavior of both synthetic and biological macromolecules and nanoparticles under different conditions of interest in industry and biomedicine. In this regard, we have set up in our laboratory several techniques for the characterization of biomacromolecules in solution, which include: (i) analytical ultracentrifugation with both absorbance and interference detection, AUC/Abs-Int; (ii) dynamic light scattering and z-potential (DLSz) and (iii) rheometry. Those experimental techniques are complemented by our continuous work in the development of computational tools that help to relate solution properties and molecular structure (size, shape and flexibility of biomolecules). Our DLSz instrument covers a wide range of sizes from 1 nm to 1000 nm, thus detecting large aggregates that are not detected by other techniques. In addition, the surface z-potential allows for the study of the stability of nanoparticles suspensions. With those techniques, we were able to study the aggregation process of gold nanoparticles suspensions under a variety of ionic strength conditions. On the other hand, the sensitivity of the AUC/Abs-Inter allowed us to determine the oligomerization state of different proteins. Some preliminary computational results have been also performed in order to elucidate the overall shape of those proteins. Finally, by means of rheometric measurements we characterized the viscoelastic behavior of some synthetic gels.