Biomolecules dynamic in solid surfaces using spectromicroscopy

Abstract

Microorganisms, biomolecules and biomembranes are usually immobilized on solid surfaces (gold, silicon, quartz, glass, carbon, nanoparticles substrates, etc.) when it is intended to study and / or apply them in biotechnology. This includes the use of fungi and bacteria in bioelectrode of biofuel cells, enzymes in biosensors, membranes in organ-on-a-chip, cell culture in microfluidic systems and antigen-antibody systems in chromatographic immunoassays. In this project, we intend to study some model systems by Spectromicroscopy in the Infrared Region (µ-FTIR), that is, a technique that allows the generation of chemical images on solid surfaces, where variations in the vibration frequency of chemical bonds are monitored point-by-point with spatial resolution. Emphasis will be given to µ-FTIR with FPA detector (focal plane array), that allows to obtain chemical images with resolution in the order of 2.7 µm, enabling the analysis of biomolecules dynamics in different matrices. Such detector also provides the simultaneous collection of spectra in 4096 isolated regions, with high statistical significance. It is highlighted the relevance of this technique in the study of molecular events hardly accessed in conventional spectrophotometers. Due to its relevance in application in biotechnology, three large groups of samples were selected: i) proteins immobilized on different solid substrates to determine mechanisms of protein-substrate interaction / aggregation through the analysis of its secondary structure; ii) IgG and IgM interaction for COVID-19 (coronavirus SARS-COV-2) and membrane proteins (eg RBD); iii) in situ monitoring the alcoholic fermentation process of the yeast Saccharomyces cerevisiae, in which the glucose is converted into ethanol.