Fabrication Of Glucose Sensor Research Articles

Fast Synthesis of PbS Nanoparticles for Fabrication of Glucose Sensor with Enhanced Sensitivity

PbS nanoparticles with average size of 12 nm have been synthesized by a novel time-saving method that combines sonochemical and laser postannealing processes, the latter being important for improved crystal quality of the nanoproduct. The crystalline quality and morphology of the PbS nanoparticles were characterized using several techniques such as Raman spectroscopy, x-ray diffraction analysis, transmission electron microscopy, diffuse reflectance spectroscopy, and energy-dispersive x-ray analysis. The as-produced PbS nanoproduct was then used to make a glucose sensor. Electrochemical measurements showed that the sensitivity of the glucose sensor based on PbS nanoparticles was 546.2 μA cm−2 mM−1, much higher than for glucose sensors based on other semiconductor materials reported in literature.

Combination of cascade chemical reactions with graphene–DNA interaction to develop new strategy for biosensor fabrication

Graphene, a single atom thick and two dimensional carbon nano-material, has been proven to possess many unique properties, one of which is the recent discovery that it can interact with single-stranded DNA through noncovalent π–π stacking. In this work, we demonstrate that a new strategy to fabricate many kinds of biosensors can be developed by combining this property with cascade chemical reactions. Taking the fabrication of glucose sensor as an example, while the detection target, glucose, may regulate the graphene–DNA interaction through three cascade chemical reactions, electrochemical techniques are employed to detect the target-regulated graphene–DNA interaction. Experimental results show that in a range from 5μM to 20mM, the glucose concentration is in a natural logarithm with the logarithm of the amperometric response, suggesting a best detection limit and detection range. The proposed biosensor also shows favorable selectivity, and it has the advantage of no need for labeling. What is more, by controlling the cascade chemical reactions, detection of a variety of other targets may be achieved, thus the strategy proposed in this work may have a wide application potential in the future.

Patterned growth of ZnO nanorods and enzyme immobilization toward the fabrication of glucose sensors

Toward the fabrication of high sensitive glucose sensors based on ZnO nanorods integrated with ZnO-based FETs, patterned growth of ZnO nanorods and enzyme immobilization on their surfaces were conducted. The patterned growth of ZnO nanorods using photoresist was successfully performed on both sputtered polycrystalline ZnO films and epitaxial singlecrystalline ZnO ones using a hydrothermal method, although choice of a proper condition is required for the latter case. Glucose oxidase (GOx), a specific enzyme for glucose detection, was immobilized with both covalent and electrostatic bonding methods. GOx immobilized ZnO nanorods were characterized with X-ray photoelectron spectroscopy, scanning electron microscopy, and colorimetric measurements indicating that the GOx was effectively immobilized on the large surface area of ZnO nanorods.