Abstract: The present invention relates to the use of a multimeric protein of the peroxiredoxin family as a scaffold protein, characterized in that one or more proteins(s) of interest are linked to one or two N- and C-terminal end(s) of one or more monomers(s) of the peroxiredoxin, said peroxiredoxin having no redox activity.

Abstract: The invention relates to a method for the comparative analysis and control of the quality of a protein preparation by means of nuclear magnetic resonance (NMR) spectrometry. This method can be used to compare three-dimensional protein conformations in different protein preparations without requiring the samples to undergo any particular preparation. In particular, the method can be used to determine if a selected protein is in the same three-dimensional conformation in different protein preparations, if it is degraded in the formulation or if it is interacting with some of the excipients present. Specifically, the method can be used for the analysis and control of the quality of therapeutic compounds, particularly biodrugs or biosimilars, in different samples, without altering said samples.