Laser-unzipped carbon nanotube based glucose sensor for separated structure of enzyme modified field effect transistor

• We used the continuous-wave laser irradiated CNT thin film as a glucose sensing film.
• The influence of the laser irradiation on CNT thin film was demonstrated.
• A sensing film of glucose sensor made by laser-irradiated CNT thin film exhibited high sensitivity and linearity for glucose detection.

A glucose sensing film composed of unzipped multiwalled carbon nanotubes (MWCNTs) via continuous-wave laser irradiation is investigated. Some structural defects decorate on MWCNTs after an acid treatment, and the MWCNTs are unzipped into sheet-shaped layers initiated from these defects after the laser irradiation. The laser-irradiated carbon nanotube thin films (CNTFs) possess higher conductance owing to larger contact area, and the side edges of unzipped CNTs could act as sensing sites for hydrogen ions. Thus the laser-irradiated CNTF as a glucose sensing film could achieve a higher sensitivity of 0.302 mV (mg/dl)−1, equal to 7.55 mV (mg/dl)−1 per centimeter square, and a larger linearity of 0.9947 than the as-sprayed one. Moreover, the fully low-temperature processes of this work also reveal the potentials for flexible and disposable biosensors.