Future Trends for In Situ Monitoring of Polycyclic Aromatic Hydrocarbons in Water Sources: The Role of Immunosensing Techniques

Abstract

Polycyclic aromatic hydrocarbons (PAHs) are hazardous environmental pollutants found in water, soil, and air. Exposure to this family of chemicals presents a danger to human health, and as a result, it is imperative to design methods that are able to detect PAHs in the environment, thus improving the quality of drinking water and agricultural soils. This review presents emerging immunoassay techniques used for in situ detection of PAH in water samples and how they compare to common-place techniques. It will discuss their advantages and disadvantages and why it is required to find new solutions to analyze water samples. These techniques are effective in reducing detection times and complexity of measurements. Immunoassay methods presented here are able to provide in situ analysis of PAH concentrations in a water sample, which can be a great complement to existing laboratory techniques due to their real-time screening and portability for immunoassay techniques. The discussion shows in detail the most relevant state-of-the-art surface functionalization techniques used in the field of immunosensors, with the aim to improve PAH detection capabilities. Specifically, three surface functionalization techniques are key approaches to improve the detection of PAHs, namely, substrate surface reaction, layer-by-layer technique, and redox-active probes. These techniques have shown promising improvements in the detection of PAHs in water samples, since they show a wider linear range and high level of sensitivity compared to traditional PAH detection techniques. This review explores the various methods used in the detection of PAH in water environments. It provides extra knowledge to scientists on the possible solutions that can be used to save time and resources. The combination of the solutions presented here shows great promise in the development of portable solutions that will be able to analyze a sample in a matter of minutes on the field.

Methodological Approaches for Monitoring Five Major Food Safety Hazards Affecting Food Production in the Galicia–Northern Portugal Euroregion

“…Modification of the electrodes, typically made of gold, glassy carbon, or indium tin oxide (ITO), with either organic molecules, polyelectrolytes, mesoporous silica, conductive polymers (i.e., polypyrrole or polyaniline), or graphene oxide, allows the fabrication of selective electrochemical sensors for a specific PAH analyte. Additionally, electrochemical sensors that have been combined with other techniques, such as immunoassays [ 155 ] or MIP [ 156 ], show a high selectivity and sensitivity, thereby allowing the analysis of multiple PAHs on a single platform.…”

Feasibility of SERS-Active Porous Ag Substrates for the Effective Detection of Pyrene in Water

“…Afterwards, the high hydrophobicity, the chemical stability, and the sorption capacity of these compounds contribute to their dispersion and persistence in soil, sediments, and water surfaces, making them ubiquitous in various worldwide locations [ 5 , 6 , 7 ]. As a matter of fact, according to the EU Water Framework Directive adopted in 2000, the maximum total levels of PAHs allowed in water should not exceed the value of 0.1 μg/L [ 8 ]. This recommendation boosted the development of novel techniques for the detection of ultra-low PAH levels in water environments.…”

Using Room Temperature Phosphorescence of Gold(I) Complexes for PAHs Sensing

“…Hence, the present investigation focuses on the design and synthesis of new 1,8-naphthalimide based gold(I) complexes that display RTP and explores their use in molecular recognition processes. In particular, we are interested in sensing polycyclic aromatic hydrocarbons (PAHs) since they are well-known environmental contaminants with toxic, mutagenic, and carcinogenic properties [ 33 , 34 ].. They can be found in different natural sources such as water and soil and are produced from fossil fuels, industrial manufacturing, residential heating, food preparation, etc.…”

“…They can be found in different natural sources such as water and soil and are produced from fossil fuels, industrial manufacturing, residential heating, food preparation, etc. In particular, low molecular weight PAHs (2–3 rings) usually show a higher concentration in water than high molecular weight PAHs (4–6 rings) since they present a higher vapor pressure and solubility in water [ 34 ]. Their planar aromatic structure makes them ideal candidates to interact with the NI-core, inducing changes on the emission properties of the gold(I) complexes used as hosts in an easy and fast process.…”