title: Photolithographic patterning of organosilane monolayer for generating large area two-dimensional B lymphocyte arrays.
abstract: High-density live cell array serves as a valuable tool for the development of high-throughput immunophenotyping systems and cell-based biosensors. In this paper, we have, for the first time, demonstrated a simple fabrication process to form the hexamethyldisilazane (HMDS) and poly(ethylene glycol) (PEG) binary molecular surface which can be used to effectively form high fidelity cell arrays. The HMDS self-assembled monolayer (SAM) on glass substrates was photolithographically patterned and its ability to physically adsorb proteins was characterized by contact angle measurement and fluorescence microscopy respectively. Passivation of the non-HMDS coated background by PEG was verified to have no impact on the pre-patterned HMDS and greatly inhibited the non-specific protein binding. Using the biotin-streptavidin complexation as an intermediate, uniform orientation and high bioactivity were achieved for the immobilized B lymphocyte specific anti-CD19 antibodies and therefore ensured the formation of high resolution B lymphocyte arrays. The cell-ligand interaction specificity was investigated and the anti-CD19 decorated micropatterns presented a much higher cell-capturing rate (88%) than those modified by non-specific ligands (15% for anti-CD5 and 7% for streptavidin). The approach was verified to be biocompatible and the properties of the antibody-modified surface were maintained after 12 h cell culture. The HMDS monolayer formation and patterning processes, and the universal HMDS/biotin-BSA/streptavidin template, provide a very simple and convenient process to generate high resolution micropatterns of cell-adhesive ligands and are extendable to form arrays of other types of cells as well.
authors.affiliation: Center for Cell Control and Department of Mechanical and Aerospace Engineering, Henry Samueli School of Engineering and Applied Science, University of California, Los Angeles, CA 90095, USA.
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.forename: Chih-Ming
authors.initials: CM
authors.lastname: Ho
mesh_terms: D001402:B-Lymphocytes / Q000737:chemistry*; D015374:Biosensing Techniques / Q000379:methods*; D020099:Coated Materials, Biocompatible / Q000737:chemistry*; D005404:Fixatives / Q000737:chemistry; D005898:Glass / Q000737:chemistry; D044085:Microfluidics / Q000379:methods*; D008954:Models, Biological; D017646:Organosilicon Compounds / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D020099:Coated Materials, Biocompatible; D005404:Fixatives; D017646:Organosilicon Compounds; D011092:Polyethylene Glycols; C024548:hexamethylsilazane