MS for investigation of time-dependent protein adsorption on surfaces in complex biological samples

Abstract

Aim: This study aims at developing a nondestructive way for investigating protein adsorption on surfaces such as biomaterials using mass spectrometry. Methods: Ventricular cerebrospinal fluid in contact with poly carbonate membranes were used as adsorption templates and on-surface enzymatic digestion was applied to desorb proteins and cleave them into peptides. Mass spectrometric analysis provided both protein identification and determination of protein specific adsorption behavior. Results: In general, the adsorption increased with incubation time but also protein-specific time-resolved adsorption patterns from the complex protein solution were discovered. Conclusion: The method developed is a promising tool for the characterization of biofouling, which sometimes causes rejection and encapsulation of implants and can be used as complement to other surface analytical techniques. One problem associated with artificial materials in the body is that proteins in the body interact with the surface, which sometimes causes rejection of the implant. In this study, a method for investigating the time-dependent protein adsorption on a surface originating from a complex biological protein solution was developed. Compared with other surface analyses, this method can identify what proteins that adsorbs on the surface. In addition, determination of protein-specific adsorption behavior in relation to incubation was possible. Generally, more proteins adsorbed to the surface with increase in incubation time.