Deposition of Functionalizing Materials on Photonic Microcantilever Chemical/Biological Sensors using Inkjet Technology
S.J. Ness, S. Kim, G.P. Nordin
Brigham Young University, US
Keywords: photonic, microcantilever, sensor, inkjet, XPS, Tween 20, glycerol, biotinylated bovine serum albumin, streptavidin
Abstract:A photonic microcantilever (PMCL) is able to sense minute quantities of substances (for example, proteins, DNA, and other biological molecules) in small-volume fluid samples. Exclusively functionalizing the top surface of a PMCL with receptors that will adsorb target molecules is central to successful microcantilever operation, and presents a unique challenge. Physical contact with the PMCL can cause the PMCL to “stick down” or break. We have therefore focused on deposition of the functionalizing material with an inkjet materials printer (Dimatix® DMP-2831 printer with 1 pL dispensing DMC-11601 cartridges). To test our uniquely designed PMCL as a sensor, we will attempt to detect streptavidin in an aqueous solution. Biotinylated bovine serum albumin (biotin-BSA) will serve as the receptor material due to its high affinity with streptavidin. Different formulations of biotin-BSA were spotted on prepared silicon slides using the Dimatix® printer. Solution additives include glycerol and a surfactant, Tween 20. The slides were then analyzed for attachment efficiency using X-ray photoelectron spectroscopy (XPS). We concluded to use a 20 mg/mL concentration of biotin-BSA with 60% glycerol and ~0.065% v/v Tween 20 to functionalize our PMCLs.