title: Writing and reading methodology for biochips with sub-100-nm chemical patterns based on near-field scanning optical microscopy.
abstract: This paper demonstrates a writing and reading methodology, which allows both to create and to detect sub-100-nm carboxyl-terminated patterns on light-transmissive quartz substrates by the same instrumental system. Such a technique, capable of creating carboxyl-terminated nanopatterns, offers several benefits for the miniaturization of biochips, since the carboxyl-terminated nanopatterns allow the easy immobilization of biomolecules by amide bond formation. As a consequence, increasingly miniaturized biochips require suitable analytical methods for the detection of nanopatterns. In our approach, carboxyl-terminated nanopatterns of down to 80 nm width were created using a photolabile silane coupling agent and a UV laser coupled to a near-field scanning optical microscope (NSOM). The same NSOM system was then used in a next step to detect the fabricated carboxyl-terminated nanopatterns after modification with a fluorescent label. Furthermore, as a first step towards biochip applications, the successful immobilization of several biomolecules, such as streptavidin, IgG and DNA on carboxyl-terminated nanopatterns was demonstrated. We have shown that our approach has the potential to lead to a new bioanalytical method, which enables one to write and to read biochips on a sub-100-nm scale by the same system.
authors.affiliation: Department of Applied Chemistry, Faculty of Science and Technology, Keio University, Yokohama, Japan.
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Kobayashi
authors.forename: Masaru
authors.initials: M
authors.lastname: Sakai
authors.forename: Akio
authors.initials: A
authors.lastname: Ueda
authors.forename: Kenichi
authors.initials: K
authors.lastname: Maruyama
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Saiki
authors.forename: Koji
authors.initials: K
authors.lastname: Suzuki
mesh_terms: D056656:Lab-On-A-Chip Devices; D046208:Microchip Analytical Procedures / Q000379:methods*; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D020527:Microscopy, Scanning Probe / Q000295:instrumentation* / Q000379:methods*; D015394:Molecular Structure; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D011791:Quartz; D013057:Spectrum Analysis; D013499:Surface Properties
chemical_list: D011791:Quartz