Engineering Cannabinoid Sensors through Solution-Based Screening of Phthalocyanines

ACS Appl Mater Interfaces. 2020 Nov 11;12(45):50692-50702. doi: 10.1021/acsami.0c17146. Epub 2020 Oct 30.


Organic thin-film transistors (OTFTs) have shown promise for a range of sensing applications, with phthalocyanine-based OTFTs demonstrated as sensors for atmospheric parameters, volatile gases, and small organic molecules including cannabinoids. However, the process of fabricating, testing, and optimizing OTFTs in a laboratory setting requires highly specialized equipment, materials, and expertise. To determine if sensor development can be expedited and thus reduce manufacturing burden, spectroelectrochemistry is applied to rapidly screen for molecular interactions between metal-free phthalocyanines and a variety of metal phthalocyanines (MPcs) and the cannabinoids Δ9-tetrahydrocannabinol (THC) or cannabidiol (CBD), with and without a cannabinoid-sensitive chromophore (Fast Blue BB). Spectral analyses are corroborated by 2D-NMR and related to measured OTFT performance. Spectroelectrochemical changes to the Q band region of the phthalocyanine spectra in the presence of analytes can be used to predict the response of OTFTs. Thus, with spectroelectrochemistry, a range of potential materials for OTFT small organic molecule-sensing applications can be quickly analyzed, and phthalocyanines with a preferred response can be selected.

Keywords: 2D-NMR; cannabis; organic thin-film transistors; phthalocyanines; sensing; spectroelectrochemistry.

MeSH terms

  • Biosensing Techniques*
  • Cannabinoids / chemistry*
  • Indoles / analysis*
  • Isoindoles
  • Molecular Structure
  • Particle Size
  • Solutions
  • Surface Properties
  • Transistors, Electronic*


  • Cannabinoids
  • Indoles
  • Isoindoles
  • Solutions
  • phthalocyanine