title: Planar nitric oxide (NO)-selective ultramicroelectrode sensor for measuring localized NO surface concentrations at xerogel microarrays.
abstract: A planar ultramicroelectrode nitric oxide (NO) sensor was fabricated to measure the local NO surface concentrations from NO-releasing microarrays of varying geometries. The sensor consisted of platinized Pt (25 microm) working electrode and a silver paint reference electrode coated with a thin silicone rubber gas permeable membrane. An internal hydrogel layer separated the Pt working electrode and gas permeable membrane. The total diameter of the sensor was <or=50 microm, and demonstrated negligible analyte trapping effects. The sensitivity and response time of the ultramicroelectrode sensor to NO were 0.19+/- 0.07 pA nM(-1) and 1-4 s, respectively, with a 5 nM limit of detection. The sensor was employed to correlate the steady-state NO surface concentration and observed platelet adhesion resistance. Results indicate that the required steady-state NO concentration necessary to inhibit platelet adhesion to the micro-patterned xerogels depends on the xerogel geometry.
authors.affiliation: Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599-3290, USA.
authors.forename: Bong Kyun
authors.initials: BK
authors.lastname: Oh
authors.forename: Mary E
authors.initials: ME
authors.lastname: Robbins
authors.forename: Mark H
authors.initials: MH
authors.lastname: Schoenfisch
mesh_terms: D000818:Animals; D015374:Biosensing Techniques / Q000295:instrumentation*; D008422:Materials Testing; D046228:Microarray Analysis / Q000379:methods*; D008839:Microelectrodes; D009569:Nitric Oxide / Q000032:analysis*; D010973:Platelet Adhesiveness; D013552:Swine
chemical_list: D009569:Nitric Oxide