Highly-Sensitive Non-Enzymatic Glucose Sensor via Nano Platinum Crystals Fabricated by Phase-Controlled Electrochemical Deposition

Abstract

In this study, non-enzymatic glucose sensors were designed and fabricated by electrochemical deposited platinum nano-crystals, including Platinum nanosphere (Pt NS), Platinum nanorose (Pt NR), and Platinum nanocubes (Pt NC) on fluorine-doped tin oxide glass. The control of the morphologies and growth types was conducted by either potentiostatic or pulse-mode potentiostatic deposition for synthesizing Pt NS, Pt NR, or Pt NC, respectively, at room temperature. Among three Pt nano-crystals, The Pt NC displayed the highest electrocatalytic activity to oxidation of glucose (glucolactone) owning to the single crystalline structure. The developed Pt NC sensor showed a fast response time (2 s), a high sensitivity of 20.75 μA/mM⋅cm, and a detection limit of 0.7 μM (at S/N ratio = 3). By setting glucose oxidation potential to 0.1 V, the Pt NC electrode provided a linear dependence (R2 = 0.99086) to glucose in a concentration range from 0.33 to 12.50 mM. The Pt NC electrodes showed stable, highly sensitive, low working oxidation potential, low loading of Pt, and rapid amperometric response in sensing glucose with excellent reproducibility and selectivity, possessing a great potential for non-enzymatic glucose sensing applications.