earticle

영어

MALDI-TOF mass spectroscopy has been used for the analysis of receptor-ligand interactions. The receptor-ligand interaction has been analyzed by the following steps: immobilization of receptor proteins, binding of ligand molecules, and analysis with MALDI-TOF mass spectroscopy (MS). For this study, the parylene-H, which is a modified polymer of para-xylene to have formyl groups on the surface, was used as a receptor binding surface. In order to apply parylene-H film for the immobilization of receptor proteins, the parylene-H was thermally deposited on the target plate to be less than 50 nm thick by microprocessor controlled parylene coater. The thickness and the roughness of parylene-H film were determined by the AFM, and the rms deviation of the surface roughness was estimated to be ± 2 nm within the area of 5 x 5 μm2. In order to analyze the receptor-ligand interaction, streptavidin and biotinylated CCP were used as a receptor protein and ligand molecule, respectively. As the first step, streptavidin was immobilized to the parylene-H film by dipping the parylene-H coated target plate to the streptavidin solution, and then analyzed by MALDI-TOF MS. From the results, no significant mass peak was found at the mass spectrum, because streptavidin was covalently immobilized to parylene-H film by forming imine bond. As the second step, the ligand molecule, biotinylated CCP in this study, was treated to the immobilized receptor proteins on the target plate. The target plate with covalently immobilized streptavidin resulted in the far higher mass signal of biotinylated CCP than physically adsorbed streptavidin target plate. These results show that the parylene-H film is feasible for the analysis of receptor-ligand interaction with MALDI-TOF MS.