Trends in Environmental Analytical Chemistry最新文献

Pesticides are major contaminants in grapes and their by-products. Different methods for sample preparation and separation are used for determining different pesticides in grapes. However, until now, the environmental friendliness of these methods has not been assessed fully. At present time, several tools such as Eco-Scale, NEMI, GAPI, AGREE are available to evaluate the environmental sustainability of methods such as sample preparation, extraction, and separation. Each tool has its benefits and drawbacks. Moreover, the results obtained with the help of each tool may lead to different conclusions. This paper is aimed to review different sample preparation methods for the determination of pesticides in grapes found in the scientific literature. The Green Analytical Procedure Index (GAPI) tool was chosen to evaluate the environmental friendliness of each methodology in this study. This research also shows the importance of using aforementioned tools in the development of future analytical methods before using practical tests. In addition to greenness, tool helps to assess assessing minimize the use of chemical hazards and avoid risks to human health and emissions to the environment. Method greenness assessment is suggested to be included in method validation protocols.

Magnetic nanoparticles (MNPs) have recently emerged as significant materials in the development of a variety of sectors, including analytical chemistry, by virtue of their unique properties making them appropriate for a wide range of applications. They have exceptional performance in extracting and enriching a wide range of target analytes such as trace pollutants due to their superparamagnetic properties, ease of separation, and surface modification as well as selective adsorption capacity. However, the toxicity of such materials has urged efforts to search for green production ways so that assuring reduced toxicity levels and permitting unlimited applications. Current research and analysis on biosynthesized green MNPs for the identification and quantification of environmental contaminants are widespread. Consequently, this review article focuses on several studies which outline novel strategies for synthesizing MNPs from green sources, as well as the future direction of research in this field. The recent applications of green MNPs (from 2016 to June 2023) in the separation and preconcentration of various pollutants including both organic and inorganic ones in different environmental matrices are demonstrated. Potential challenges and future perspectives are also highlighted. This review can serve as a roadmap and inspire further research in this area.

In response to the increasing demand for precise diagnosis in criminal investigations, magnetic extraction techniques have gained increased attention in forensic analysis. Magnetic extraction is usually based on magnetic materials that could be functionalized to obtain the appropriate functional groups for increasing selectivity and enhancing the analyte recovery. They offer efficient analyte separation and/or enrichment from samples with complex matrices when used in magnetic extraction. This review emphasizes several types of magnetic extraction techniques (including solid phase extraction, stir bar sorptive extraction, liquid phase microextraction, and others) with their evolution in forensic science. It also provides insight into the potential benefits of combining forensic science and magnetic extraction, which will result in superior scientific analysis. The challenges and prospects of developing various magnetic extraction techniques in forensic science are also addressed.

Diffusive gradients in thin films (DGT) is a powerful analytical tool that has been widely used to obtain concentration and distribution data of target analytes in waters, soils, and sediments. While many review papers have discussed the development and application of DGT, there has been no comprehensive review specifically focusing on its use in coastal sediments, which are subject to complex and diverse environmental conditions and can be easily affected by anthropogenic activities. Coastal sediments can act as a source or a sink of trace metals and oxyanions to the overlying water, making it essential to use analytical methods with high resolution and selectivity. This paper provides a thorough review of the research applications of DGT in coastal sediments, including nearshore, estuarine, and intertidal sediments. The review also presents a brief introduction to DGT devices and deployment methods in coastal sediment environments and discusses in details the reported cases of DGT application since 2010, which include metal and oxyanion mobilization and interaction, pollutant monitoring and risk assessment, diagenetic processes, as well as the kinetics and mechanism of analyte transfer across the sediment-water interface. Finally, the review discusses the expected future progress of DGT technique.

The current state-of-the-art of nanomaterial-based electrochemical sensors in flow injection (NBES-FI) platforms for in-line determination of environmental pollutants (since 2013 to mid-2023) is herein critically reviewed. The synergistic effects of FI platforms and nanomaterial-based modifiers, such as metal nanoparticles and carbon-based nanomaterials, for minimizing electrode fouling, alleviating overpotential, and boosting the overall figures of merit are discussed in detail. The role of experimental parameters including (i) the electrode nature, shape, design and configuration, (ii) the synthetic routes of (nano)materials, and (iii) the electrochemical detection technique on the analytical performance of NBES-FI is thoroughly evaluated. Current challenges and needs for real-world exploitation of NBES-FI in environmental settings are outlined along with perspectives for the integration of NBES-FI with microextraction approaches and the exploitation of 3D printing technology for fabrication of customized fluidic platforms.

Hormones are an important class of biomolecules as they regulate the physiological responses in the living organisms. Recently, nanomaterials-based biosensors have been widely researched due to their outstanding merits like stabilty, selectivity, biocompatibility, facile synthetic approach, and cost-effectiveness. In this review, we cover in detail the recent advancements of nanomaterials (carbon dots, carbon nanotubes, metal nanoparticles, metal oxides, metal-organic frameworks, metal nanoclusters and quantum dots) in electrochemcial, colorimetric and fluorescence sensing of plant hormones. This review also provides a brief outline on the classificaiton of phytohormones and the sample preparation appraoches for the extraction of phytohormones prior to their identification by various analytical techniques. This review will focus on the selected research papers on nanomaterials as electrochemical, colorimetric and fluorescent sensors for the plant hormones detection from the last twelve years (i.e., 2011 −2023). Nanomaterials integrated analytical techniques (electrochemcial, colorimetric and fluorescence) offer to detect plat hormones with lower detection limits (fM to µM and ng/mL to pg/mL). Importantly, nanomaterials integrated analytical strategies have been successfully detected plant hormones with minimal volumes and sample preparations. The various advantages and limitations of techniques have been also overviewed. The challenges and future perspectives of nanomaterials-based electro- and optical sensors for the analysis of plant hormones are discussed in detail.

Background

One of the newly developed two-dimensional (2D) materials, MXenes Quantum dots (MQDs) has become a hot topic in materials science over the past ten years. Their potential in fluorescent sensing applications has also gained a lot of attention after the recognition of their distinctive features.

Aim of review

The review signifies the understanding of the synthesis, mechanism, and surface engineering of MQDs for their application as fluorescence sensors.

Findings

The MQDs are prepared by simple top-bottom, bottom-up, and advanced microwave approaches. The mechanism is based on quenching which involves Forster Resonance Energy Transfer (FRET), Inner Filter Effect (IFE), or Photo Induced Electron Transfer (PET) in a broad range of sensing applications. However, sometimes a new analyte is added to recover the fluorescence quenching. Doping with a heteroatom (N, P, S or metal atoms) and co-doping (N-P, N-S, N-, Pt, etc.) has been frequently used to overcome the drawbacks of MQDs such as aggregation, oxidation, and low quantum yield. MQDs modification can be realized by covalent bonding, aryl diazonium chemistry, or non-covalent interactions. Moreover, surface defects are removed to enhance the Photoluminescence Quantum Yield (PLQY) by passivation. However, overcoming the challenges of MQDs synthesis restricted to Ti, detail sensing mechanistic study, and advancement in surface engineering (modification and passivation) could lead to future highly efficient and vast MQDs sensors applications.

Ionic liquid mediated carbon dots (IL-CDs) are being emerged as new sensing probe for the detection of various chemical entities. Their unique features i.e. physical, chemical and optical properties along with their eco-friendly nature are the main sources of attraction for researchers. The induction of ionic moieties in addition to their naturally existing surface functionalities such as ―OH, ―COOH, ―NH₂ on CDs make them a good option for sensing applications. This review focuses on a systematic literature related to the employment of IL-CDs as sensing probes for various chemical species. Moreover, IL-CDs have been critically evaluated compared to ordinary CDs in terms of structural difference, versatility in mode of sensing, types of entities being sensed and performance efficiency to highlight the spaces which have to address in near future.

Extraordinary features of carbon dots (CDs) including their biocompatibility, water solubility, stability, tunability, low cost and scalability make them as promising nanomaterials for a number of application areas such as fluorescent nanosensors. Combination of these superiorities with the advantages of molecularly imprinted polymers (MIPs) such as high affinity, selectivity, robustness and reusability provides the development of novel fluorescent nanosensors with enhanced sensitivity and selectivity towards the target compounds. This paper provides an overview of green approaches for the synthesis of CDs, integration of CDs with MIPs and recent developments on the design and construction of sensitive green CDs/MIPs-based fluorescent nanosensors for the detection of various pollutants (i.e. antibiotics, pesticides, heavy metals and explosive compounds etc.) in environmental samples.

Molecular-level investigation of crude oil has become an essential part of oil spill research, It facilitates the assessment of oil behavior, fate, impacts, as well as the evaluation of oil spill origins, toxic substances, and the effect of such incidents. Notable oil spill incidents, such as the Deepwater Horizon, have emphasized the need for molecular-level information on spilled oil to evaluate and monitor environmental damage. In this study, the term 'Environmental Petroleomics' is defined. During the weathering of spilled oil, various effects can alter the oil's chemical composition, including evaporation, dispersion, photo-oxidation, and microbial degradation. The major toxic compounds in the spilled oil are aromatic compounds, followed by polar oxygenated aromatic compounds. Although gas chromatography-mass spectrometry (GC-MS) is an effective approach for compositional analysis of crude oil, it falls short in its ability to separate individual compounds in the weathered oil. This is particularly challenging when dealing with weathered oil enriched with polar oxygen- and sulfur-containing compounds that emerge during the weathering process . Ultra-high-resolution mass spectrometry (UHR-MS) has played a key role in the development of Environmental Petroleomics, proving effective in characterizing various polar species. This review explores the application of ultra-high-resolution mass spectrometry for oil spill research. The study concludes that the toxicity of weathered crude oils results from the photo-oxidation of crude oil molecules into highly oxygenated, water-soluble species. Prospective research in environmental petroleomics concerning the analysis of oil spills may direct its attention towards innovating novel methodologies. These could encompass high-resolution imaging of oil spills, time-resolved analysis of spill dynamics, integration of ultra-high-resolution mass spectrometry (UHR-MS) with complementary techniques, and the utilization of UHR-MS for biomarker analysis.