Electroanalysis of proteins and peptides via amino acid residues

Protein and peptide electroanalysis on solid electrodes is not limited to six ‘electroactive’ amino acid residues, but can involve almost all amino acids. In addition to the L-enantiomers of amino acids, the D-enantiomers should also be taken into account. The 3D-structure and large molecular weight affect electrochemical behavior of peptides and proteins compared to free amino acids. Voltammetry and amperometric flow-injection analysis allow one to detect protein molecules and to register their mutations, post-translational modifications, denaturation, degradation, aggregation, and complexation with metal ions by the oxidation signal of amino acid residues. Short-chain bioactive peptides should be considered as a new challenge for electrochemistry due to their wide range of biological activities and applications, including antioxidant, antihypertensive, antiobesity, antimicrobial, and anticancer.