2D-Raman correlation spectroscopy as a method to recognize of the interaction at the interface of carbon layer and albumin

In modern nanomaterial production, including those for medical purposes, carbon based materials are important, due to their inert nature and interesting properties. The essential attribute for biomaterials is their biocompatibility, which indicates way of interactions with host cells and body fluids. The aim of our work was to analyze two types of model carbon layers differing primarily in topography, and developing their interactions with blood plasma proteins. The first layer was formed of pyrolytic carbon C (CVD) and the second was constructed of multi-walled carbon nanotubes obtained by electrophoretic deposition (EPD), both set on a Ti support. The performed complex studies of carbon layers demonstrate significant dissimilarities regarding their interaction with chosen blood proteins, and points to the differences related to the origin of a protein: whether it is animal or human. However the basic examinations, such as: wettability test and nano sctatch tests were not sufficient to explain the material properties. In contrast, Raman microspectroscopy thoroughly decodes the phenomena occurring at the carbon structures in contact with the selected blood proteins. The 2D correlation method selects the most intense interaction and points out the different mechanism of interactions of proteins with the nanocarbon surfaces and differentiation due to the nature of the protein and its source: animal or human. The 2D correlation of the Raman spectra of the MWCNT layer+HSA interphase proves an increase in albumin β-conformation. The presented results explain the unique properties of the Clayers (CVD) in contact with human albumin.