Quartz-Crystal Microbalance Measurements of Cd19 Antibody Immobilization on Gold Surface and Capturing B Lymphoblast Cells: Effect of Surface Functionalization

Abstract

We have investigated different surface functionalization methods to immobilize CD19 antibody on gold surface to capture B lymphoblast cells associated with the acute lymphoblastic leukemia disease. Quartz Crystal Microbalance measurements were performed to analyze the binding kinetics of each layer and determine the optimum method, which results in higher cell capture rates. The random orientation of antibody and oriented antibody through protein G was investigated and protein G presence resulted in 15,2Hz frequency shift for 10(4)cells/mL. The 3-mercaptopropyltrimethoxysilane (MPS) and 11-Mercaptoundecanoic acid (MUA) coatings of gold surface together with 4-(N-Maleimidomethyl)cyclohexane-1-carboxylic acid 3-sulfo-N-hydroxysuccinimide ester sodium salt (Sulfo-SMCC) and N-Ethyl-N'-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC)/N-hydroxysulfosuccinimide (NHS) linker layers were tested on QCM for protein G and antibody binding. The results indicate that MUA, EDC/NHS, protein G, antibody CD19 is the optimum surface modification among the tested combinations. By using the optimum surface functionalization method, minimum 10(3) cell per mL was measured as 1.9Hz frequency shift.