A robust method of determination of high concentrations of peptides and proteins

In this paper, we pioneer application of a unique method of protein determination by coloring peptide bonds for analysis of a variety of biomolecules with different grades of purity (e.g., oligopeptides, membrane, and glycol proteins). We demonstrated that the calibration curve for all studied molecules is universal and linear within 0.1 to 1.2 mg protein content range. The assay thus can be used to analyze peptides without preliminary dilutions and calibration in up to 1 g/ml solutions of peptides, which is crucial for many biotechnological processes, such as development of coatings, scaffolds, and biocompatible materials.