Preparation and Application of Fullerene C60‐Polymers in Piezoelectric Quartz Crystal Sensors for Hemoglobin and Olefins

Abstract

The C60-polycinnamaldehyde (C 60 -PCA) and C60-polyphenylacetylene (C60-PPA) polymers were synthesized by the Friedel-Craft reaction and applied as piezoelectric (PZ) quartz crystal coating materials. A C60-polycinnamaldehyde (PCA) coated piezoelectric quartz crystal liquid sensor with a homemade computer interface was prepared and applied as a PZ hemoglobin sensor. The adsorption of hemoglobin onto the C60-PCA coated crystal resulted in a decreased oscillating frequency. The variations in crystal frequency were converted to voltage with a frequency to voltage converter, followed by amplification with OPA and data acquisition with an analog to digital converter. The PZ hemoglobin sensor exhibited good sensitivity of 6530 Hz/(mg/mL) with a detection limit at the ppm level for hemoglobin. Further, a C60-polyphenylacetylene (C60-PPA) coated piezoelectric quartz crystal gas sensor with an Intell-8255 data processing system for various olefin vapors was also made. The aromatic hydrocarbons such as toluene seem to have greater adsorption onto C60-PPA membrane than alkynes, alkenes, and alkanes. The adsorption of polycyclic aromatic hydrocarbons (PAHs) onto the C 60 -PPA membrane was also examined. The C60-PPA coated PZ crystal gas sensor showed much better sensitivity for PAHs than for other olefins such as toluene, 1-hexyne and 1-hexene, and a much larger frequency shift for naphthalene than other PAHs was also found.