Sensitive Detection of Aromatic Molecules by Laser Photoacoustic Spectrometry: Signal Enhancement by Fluorescence Quencher

Highly sensitive detection of aromatic molecules has been investigated by pulsed laser excitation. A cylindrical cell surrounded by a piezoelectric transducer has improved the detection limit. Fluorescence quencher, CH₃NO, increased the photoacoustic signal of perylene up to three times and the signal-to-noise ratio by about 50%. Typical detection limits of pyrene and perylene were 0.4 ppb in hexane and 6.7 ppb in methanol with nitromethane, respectively.