Application of integrated SECM ultra-micro-electrode and AFM force probe to biosensor surfaces.
The integration of scanning electrochemical ultra-micro-electrode (UME) with atomic force microscope cantilever probe have been achieved by using a homemade photolithography system. A gold-film-coated AFM cantilever was insulated with photo resist coating and a pointed end of the AFM probe was opened by illuminating with maskless arbitrary optical micro-pattern generator. To realize precise control of probe sample distance constantly, the resulting scanning electrochemical microscopy (SECM)-AFM probe was operated using a dynamic force microscopy (DFM) technique with magnetic field excitation. From a steady-state voltammetric experiment, the effective electrode diameters of the probes thus prepared were estimated to be from 0.050 to 6.2 microm. The capability of this SECM-AFM probe have been tested using gold comb in the presence of Fe(CN)(6)(3-). The simultaneous imaging of the topography and electrochemical activity of the strip electrode was successfully obtained. We also used the SECM-AFM to examine in situ topography and enzymatic activity measurement. Comparison of topography and oxidation current profiles above enzyme-modified electrode showed active parts distribution of biosensor surface.
Hirata
Yoshiki
Y
National Institute of Advanced Industrial Science and Technology (AIST), Central 6, Higashi 1-1-1 Tsukuba, Ibaraki, 305-8566, Japan. y-hirata@aist.go.jp
Yabuki
Soichi
S
Mizutani
Fumio
F
D015374:Biosensing Techniques / Q000295:instrumentation*; D004563:Electrochemistry / Q000295:instrumentation* / Q000379:methods; D004867:Equipment Design; D019544:Equipment Failure Analysis / Q000295:instrumentation / Q000379:methods*; D005240:Feasibility Studies; D005949:Glucose Oxidase / Q000032:analysis* / Q000648:ultrastructure*; D008422:Materials Testing / Q000295:instrumentation / Q000379:methods; D008853:Microscopy / Q000295:instrumentation* / Q000379:methods; D018625:Microscopy, Atomic Force / Q000295:instrumentation* / Q000379:methods; D013499:Surface Properties
D005949:Glucose Oxidase