Size-Based Norfentanyl Detection with SWCNT@UiO-MOF Composites

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Sensing

Background:

• Single-walled carbon nanotube (SWCNT) and metal-organic framework (MOF) composites are utilized in field-effect transistor (FET) sensors.
• Analyte detection in these sensors relies on restricted ion diffusion around the SWCNT surface.

Purpose of the Study:

• To explore the detection of norfentanyl (NF) using SWCNT@MOF FET sensors with varying pore sizes.
• To investigate the influence of MOF pore size and analyte diffusion on sensor response.

Main Methods:

• Synthesis of four SWCNT@MOF composites: UiO-66, UiO-66-NH2, UiO-67, and UiO-67-CH3.
• Fabrication and testing of liquid-gated FET devices using these composites for NF detection.
• Evaluation of sensor response to other drug metabolites: norhydrocodone (NH), benzoylecgonine (BZ), and normorphine (NM).

Main Results:

• SWCNT@UiO-67 FET devices exhibited the highest sensing response to NF.
• SWCNT@UiO-66 and SWCNT@UiO-66-NH2 devices showed no improvement over bare SWCNTs.
• Sensing response was influenced by the size match between NF and the MOF channel, as well as NF diffusion.
• The SWCNT@UiO-67 sensor detected NM (similar size to NF) but not NH or BZ (different sizes).

Conclusions:

• SWCNT@MOF FET sensors can detect NF, with SWCNT@UiO-67 showing optimal performance.
• Pore size and analyte diffusion dynamics within the MOF are critical factors for sensor sensitivity and specificity.
• While effective against larger molecules, sensor arrays with diverse pore sizes and chemistries are necessary for enhanced specificity.