Colorimetric assay of tyrosinase inhibition using melanocyte laden hydrogel fabricated by digital light processing printing

Abstract Colorimetric assay of melanogenesis inhibition was demonstrated with polyethylene glycol tetraacrylate (PEG-4A) hydrogel structures embedding melanocyte cells. The cell laden PEG-4A hydrogel structure was prepared by digital light processing printing using biocompatible visible range of light. The melanocyte in PEG-4A hydrogel structure showed a high cell compatibility and expressed melanin changing a color of hydrogel to black. The inhibition of melanin expression was evaluated by injecting a different concentration of arbutin and kojic acid to the cell laden hydrogel structure in a 3D printed microfluidic chip. The tyrosinase inhibitors prevented a color change of the hydrogel pad according to the dosage showing a similar detecting efficiency to a commercial melanogenesis assay kit.