Producing Ink That Emits Blue Light: Introduction of Dehydration Reaction to Combine Biomolecules Using Maillard Reaction

To encourage the learning of a dehydration condensation reaction between an amino acid and sugar using a visually impressive concrete phenomenon, this work presents a method to produce an ink with a coffee-like brown color from colorless reactants via a simple (heating an aqueous solution) and short (15 min) chemical reaction using the Maillard reaction. The ink exhibits whitish-blue photoluminescence upon exposure to ultraviolet light. Inks with various colors, such as yellow, red, green, and blue, can also be prepared by changing experimental conditions such as pH and temperature. The intended audiences of this work are instructors of general chemistry courses for undergraduate students in the faculties of nursing or engineering, and the potential targets of this work are instructors in the fields of life, food, and natural sciences because the proposed method utilizes readily available and familiar biomolecules.