Trace-Level Phenolics Detection Based on Composite PAN-MWCNTs Nanofibers.

In view of major concerns regarding toxicity (genotoxic, mutagenic, hepatotoxic) of phenolics, there is an on-going necessity for sensitive and accurate analytical procedures for detection and measurements in environmental field, water, and food quality control. The current study proposes composite polyacrylonitrile nanofibrous assemblies enriched with multi-wall carbon nanotubes (PAN-MWCNTs NFs) as suitable immobilization platforms for cross-linking of tyrosinase in detection of both diphenols and monophenols, which are of much interest in water contamination. The prepared biosensor (Pt/PAN-MWCNTs/Tyr) showed high sensitivity in catechol detection (362.5 mA/M.cm2 ) and moderate sensitivity for the two monophenols (phenol, p-chlorophenol) with 14.79 and 25.46 mA/M.cm2 , respectively. The LOD values of the sensor were in the nanomolar range: 4.42×10-9 , 4.06×10-7 and 1.05×10-7  M for catechol, phenol and p-chlorophenol, respectively, allowing detection of trace amounts of phenolics in spiked water samples.