Fluorescence, Absorption, and Excitation Spectra of Polycyclic Aromatic Hydrocarbons as a Tool for Quantitative Analysis

Abstract

An experiment suitable for college junior or senior students in the analytical instrumental analysis laboratory that demonstrates the analysis of PAHs (benzo[a]anthracene, benzo[k]fluoranthene, benzo[a]pyrene, chrysene, and phenanthrene) using absorption and fluorescence spectroscopy is described. This experiment is carried out during one seven-hour instrumental analysis laboratory. It could also be used in a physical chemistry laboratory to demonstrate fundamental spectroscopic and photochemical principles. A Beer–Lambert plot for an absorption peak of each PAH was obtained and used to determine the molar absorptivities. The effect of heavy atoms as quenchers of fluorescence was studied by using 1-bromoheptane and 1,7-dibromoheptane, and Stern–Volmer plots were prepared to determine the ratios of the quenching rate constants to the fluorescence rate constant, k Q/k f. The experiment is also useful as an experiment preceding the determination of PAHs by HPLC with absorption and fluorescence detection as described earlier ( J. Chem. Educ. 1998, 75, 1599).

Transfer of benzo[a]pyrene from microplastics to Artemia nauplii and further to zebrafish via a trophic food web experiment: CYP1A induction and visual tracking of persistent organic pollutants

“…Because BaP shows a strong autofluorescence at 405 nm with a second peak at approximately 430 nm , BaP uptake and transfer could be documented visually, but only qualitatively with the help of the fluorescence microscope (excitation filter: 340–380 nm, emission filter: 435–485 nm, 100 ms exposure). With a minimal detection limit of 0.12 μg/L, this method is sensitive enough to detect the concentrations of BaP used in the present study.…”

“…Still, as a conclusion, the EROD assay did not prove to be a suitable method to detect low concentrations of POPs transferred by microplastics. The characteristic of PAHs to fluoresce and especially the tracking of BaP and its derivatives has been studied with respect to environmental concerns [34,49]. In a 1985 study, Vahakangas et al [33] quantified BaP-diol epoxide (BPDE)-deoxyribonucleic acid (DNA) adducts, and fluorescence emission maxima were found at 382 nm for BPDE-DNA and at 379 nm for BaPtetrols and BaP-triol.…”

“…In zebrafish, the retention and effects of microplastic particles within the intestinal tract were analyzed, and potential biological effects of the microplastic‐borne model contaminant BaP were monitored via the induction of cytochrome P450 1A (CYP1A) in the liver of exposed zebrafish in an ethoxyresorufin‐ O ‐deethylase (EROD) assay. Benzo[ a ]pyrene was used because 1) it is an environmentally relevant substance also found on microplastics; 2) it is a moderate EROD inducer ; and 3) it displays a strong autofluorescence , which can be used to visually track its transfer from plastics to organisms.…”

Spectroelectrochemical Sensing of Pyrene Metabolites 1-Hydroxypyrene and 1-Hydroxypyrene-glucuronide

“…The detection limit for 1-pyOH was calculated to be 1 Â 10 À8 M using the previously described method of three times the experimentally determined standard deviation of the blank (261 counts) and the slope of the linear equation obtained from the calibration curve. 35 Figure 5B shows the calibration curve generated for 1-pyOglu. Again, a linear relationship between the log of Δ and the log of in sample solutions ranging from 1 nM to 1 μM was observed.…”

UV luminescence characterisation of organics in Mars-analogue substrates

“…Distinct UV-excited photoluminescence spectra are emitted by many organic molecules, ranging from polyaromatic hydrocarbons (PAHs), to some amino-acids, as well as more complex mixtures of dissolved organic matter (DOM) (Chen et al 2003, Rivera-Figueroa et al 2004, Carrier et al 2016. In addition, inorganic substrates can also produce a photoluminescence response following UV excitation (Gaft et al 2015).…”