title: Flexible thick-film glucose biosensor: influence of mechanical bending on the performance.
abstract: The influence of the bending-induced mechanical stress of flexible Nafion/GOx/carbon screen-printed electrodes (SPEs) upon the performance of such glucose biosensors has been examined. Surprisingly, such flexible enzyme/polymer-SPEs operate well following a severe bending-induced mechanical stress (including a 180 degrees pinch), and actually display a substantial sensitivity enhancement following their mechanical bending. The bending-induced sensitivity enhancement is observed only for the amperometric detection of the glucose substrate but not for measurements of hydrogen peroxide, catechol or ferrocyanide at coated or bare SPEs. These (and additional) data indicate that the bending effect is associated primarily with changes in the biocatalytic activity. Such sensitivity enhancement is more pronounced at elevated glucose levels, reflecting the bending-induced changes in the biocatalytic reaction. Factors affecting the bending-induced changes in the performance are examined. While our data clearly indicate that flexible enzyme/polymer-SPEs can tolerate a severe mechanical stress and hold promise as wearable glucose biosensors, delivering the sample to the active sensor surface remains the major challenge for such continuous health monitoring.
authors.affiliation: Department of NanoEngineering, University California San Diego, La Jolla, CA 92093, USA.
authors.forename: Min-Chieh
authors.initials: MC
authors.lastname: Chuang
authors.forename: Yang-Li
authors.initials: YL
authors.lastname: Yang
authors.forename: Ta-Feng
authors.initials: TF
authors.lastname: Tseng
authors.forename: Tzuyang
authors.initials: T
authors.lastname: Chou
authors.forename: Shyh-Liang
authors.initials: SL
authors.lastname: Lou
authors.forename: Joseph
authors.initials: J
authors.lastname: Wang
mesh_terms: D001234:Aspergillus niger / Q000201:enzymology; D015374:Biosensing Techniques / Q000295:instrumentation* / Q000379:methods; D002138:Calibration; D002244:Carbon / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D005465:Fluorocarbon Polymers / Q000737:chemistry; D005947:Glucose / Q000032:analysis* / Q000378:metabolism; D005949:Glucose Oxidase / Q000737:chemistry / Q000378:metabolism; D011327:Printing; D013314:Stress, Mechanical; D013997:Time Factors
chemical_list: D005465:Fluorocarbon Polymers; C040402:perfluorosulfonic acid; D002244:Carbon; D005949:Glucose Oxidase; D005947:Glucose