Trace determination of triclosan and triclocarban in environmental water samples with ionic liquid dispersive liquid-phase microextraction prior to HPLC–ESI-MS–MS

Triclosan and related compounds in the environment: Recent updates on sources, fates, distribution, analytical extraction, analysis, and removal techniques

Triclosan (TCS) has been widely used in daily life because of its broad-spectrum antibacterial activities. The residue of TCS and related compounds in the environment is one of the critical environmental safety problems, and the pandemic of COVID-19 aggravates the accumulation of TCS and related compounds in the environment. Therefore, detecting TCS and related compound residues in the environment is of great significance to human health and environmental safety. The distribution of TCS and related compounds are slightly different worldwide, and the removal methods also have advantages and disadvantages. This paper summarized the research progress on the source, distribution, degradation, analytical extraction, detection, and removal techniques of TCS and related compounds in different environmental samples. The commonly used analytical extraction methods for TCS and related compounds include solid-phase extraction, liquid-liquid extraction, solid-phase microextraction, liquid-phase microextraction, and so on. The determination methods include liquid chromatography coupled with different detectors, gas chromatography and related methods, sensors, electrochemical method, capillary electrophoresis. The removal techniques in various environmental samples mainly include biodegradation, advanced oxidation, and adsorption methods. Besides, both the pros and cons of different techniques have been compared and summarized, and the development and prospect of each technique have been given.

Advances Brought by Hydrophilic Ionic Liquids in Fields Involving Pharmaceuticals

The negligible volatility and high tunable nature of ionic liquids (ILs) have been the main drivers of their investigation in a wide diversity of fields, among which is their application in areas involving pharmaceuticals. Although most literature dealing with ILs is still majorly devoted to hydrophobic ILs, evidence on the potential of hydrophilic ILs have been increasingly provided in the past decade, viz., ILs with improved therapeutic efficiency and bioavailability, ILs with the ability to increase drugs' aqueous solubility, ILs with enhanced extraction performance for pharmaceuticals when employed in biphasic systems and other techniques, and ILs displaying low eco/cyto/toxicity and beneficial biological activities. Given their relevance, it is here overviewed the applications of hydrophilic ILs in fields involving pharmaceuticals, particularly focusing on achievements and advances witnessed during the last decade. The application of hydrophilic ILs within fields involving pharmaceuticals is here critically discussed according to four categories: (i) to improve pharmaceuticals solubility, envisioning improved bioavailability; (ii) as IL-based drug delivery systems; (iii) as pretreatment techniques to improve analytical methods performance dealing with pharmaceuticals, and (iv) in the recovery and purification of pharmaceuticals using IL-based systems. Key factors in the selection of appropriate ILs are identified. Insights and perspectives to bring renewed and effective solutions involving ILs able to compete with current commercial technologies are finally provided.

Novel semi-automated graphene nanosheets based pipette-tip assisted micro-solid phase extraction as eco-friendly technique for the rapid detection of emerging environmental pollutant in waters

In this work, a new semi-automated syringe infusion-pump assisted graphene nanosheets (GNSs) based pipette-tip micro-solid phase extraction (PT-μSPE) as a green sample preparation technique was demonstrated for the sensitive analysis of emerging environmental pollutant in environmental waters using HPLC-UV. Microwave-assisted synthesized GNSs powder was packed into a 100 μL pipette-tip (as PT-μSPE cartridge) connected with a commercial plastic syringe (contains water sample). This setup was attached to a programmable auto-syringe infusion pump for the GNSs-PT-μSPE process. Triclosan (TCS) is an emerging environmental pollutant chosen as a target analyte to examine the extraction capacity and feasibility of GNSs as a sorbent material for PT-μSPE. Parameters affecting the extraction capability were systematically evaluated and thoroughly optimized. At optimized experimental parameters, excellent linearity (r² = 0.9979) was achieved over the concentration range of 2-250 ng mL^-1 for TCS, with a detection limit of 0.5 ng mL^-1. Applicability of the presented method was examined with real water samples, and extraction recoveries obtained were ranged between 94.6-102.4% with RSD less than 7.8%. The presented protocol is a simple, semi-automated, eco-friendly, low-cost, and efficient sample pretreatment technique for quick analysis of TCS in environmental wastewaters.

The Influence of Ionic Liquids on the Effectiveness of Analytical Methods Used in the Monitoring of Human and Veterinary Pharmaceuticals in Biological and Environmental Samples-Trends and Perspectives

Recent years have seen the increased utilization of ionic liquids (ILs) in the development and optimization of analytical methods. Their unique and eco-friendly properties and the ability to modify their structure allows them to be useful both at the sample preparation stage and at the separation stage of the analytes. The use of ILs for the analysis of pharmaceuticals seems particularly interesting because of their systematic delivery to the environment. Nowadays, they are commonly detected in many countries at very low concentration levels. However, due to their specific physiological activity, pharmaceuticals are responsible for bioaccumulation and toxic effects in aquatic and terrestrial ecosystems as well as possibly upsetting the body's equilibrium, leading to the dangerous phenomenon of drug resistance. This review will provide a comprehensive summary of the use of ILs in various sample preparation procedures and separation methods for the determination of pharmaceuticals in environmental and biological matrices based on liquid-based chromatography (LC, SFC, TLC), gas chromatography (GC) and electromigration techniques (e.g., capillary electrophoresis (CE)). Moreover, the advantages and disadvantages of ILs, which can appear during extraction and separation, will be presented and attention will be given to the criteria to be followed during the selection of ILs for specific applications.

Parabens and triclosan in shellfish from Shenzhen coastal waters: Bioindication of pollution and human health risks

This work aimed to determine the concentrations of parabens and triclosan (TCS) in shellfish from coastal waters of Shenzhen, South China. A method of isotope dilution with high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was used to determine TCS and five paraben analogues, including methyl paraben (MeP), ethyl paraben (EtP), propyl paraben (PrP), butyl paraben (BuP), and benzyl paraben (BeP), in 186 shellfish samples covering eight species. Concentrations of parabens and TCS were 0.13-25.5 ng/g wet weight (ww) and <LOQ-6.51 ng/g ww, respectively, indicating their ubiquitous contamination in Shenzhen coastal waters. MeP was the most predominant paraben, followed by EtP and PrP. These three analogues accounted for more than 95% of the total concentrations of parabens. The "high" estimated daily intakes of parabens and TCS with the 95th percentage concentrations were estimated to be 2.15-26.1 and 0.41-10.3 ng/kg bw/day, respectively, much lower than the acceptable dietary intakes of parabens (1 × 10⁷ ng/kg bw/day) and TCS (200 ng/kg bw/day), indicating no significant human health risks from shellfish consumption in the studied region. To our knowledge, this is the first report on the occurrences of parabens and TCS in shellfish products from Shenzhen coastal waters.

Effects of triclosan (TCS) on fecundity, the antioxidant system, and oxidative stress-mediated gene expression in the copepod Tigriopus japonicus

Triclosan (TCS) is an antimicrobial agent that has been widely dispersed and detected in the marine environment. However, the effects of TCS in marine invertebrates are poorly understood. In this study, the effects of TCS on life cycle history (e.g. mortality and fecundity) along with cellular reactive oxygen species (ROS) levels, GSH content, antioxidant enzymatic activities, and mRNA expression levels of oxidative stress-mediated genes were measured in the copepod Tigriopus japonicus. The no observed effect concentration (NOEC) and median lethal concentration (LC50) of TCS in the adult stage were determined to be 300μg/L and 437.476μg/L, respectively, while in the nauplius stages the corresponding values were 20μg/L, and 51.76μg/L, respectively. Fecundity was significantly reduced (P<0.05) in response to TCS at 100μg/L. Concentration- and time-dependent analysis of ROS, GSH content (%), and antioxidant enzymatic activities (e.g. GST, GPx, and SOD) were significantly increased (P<0.05) in response to TCS exposure. Additionally, mRNA expression of detoxification (e.g., CYPs) and antioxidant (e.g., glutathione S-transferase-sigma isoforms, Cu/Zn superoxide dismutase, catalase) genes was modulated in response to TCS exposure at different concentrations over a 24h period. Our results revealed that TCS can induce reduced fecundity and oxidative stress with transcriptional regulation of oxidative stress-mediated genes with activation of the antioxidant system in the copepod T. japonicus.

Application of an ionic-liquid combined with ultrasonic-assisted dispersion ofgold nanoparticles for micro-solid phase extraction of unmetabolized pyridoxine and folic acid in biological fluids prior to high-performance liquid chromatography

A facile and efficient protocol was suggested for the synthesis of gold nanoparticles (Au NPs) and their subsequent transfer to aqueous solution using 1-hexyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, following vigorous shaking with ultrasonic waves.

Microextraction techniques coupled to liquid chromatography with mass spectrometry for the determination of organic micropollutants in environmental water samples

Until recently, sample preparation was carried out using traditional techniques, such as liquid–liquid extraction (LLE), that use large volumes of organic solvents. Solid-phase extraction (SPE) uses much less solvent than LLE, although the volume can still be significant. These preparation methods are expensive, time-consuming and environmentally unfriendly. Recently, a great effort has been made to develop new analytical methodologies able to perform direct analyses using miniaturised equipment, thereby achieving high enrichment factors, minimising solvent consumption and reducing waste. These microextraction techniques improve the performance during sample preparation, particularly in complex water environmental samples, such as wastewaters, surface and ground waters, tap waters, sea and river waters. Liquid chromatography coupled to tandem mass spectrometry (LC/MS/MS) and time-of-flight mass spectrometric (TOF/MS) techniques can be used when analysing a broad range of organic micropollutants. Before separating and detecting these compounds in environmental samples, the target analytes must be extracted and pre-concentrated to make them detectable. In this work, we review the most recent applications of microextraction preparation techniques in different water environmental matrices to determine organic micropollutants: solid-phase microextraction SPME, in-tube solid-phase microextraction (IT-SPME), stir bar sorptive extraction (SBSE) and liquid-phase microextraction (LPME). Several groups of compounds are considered organic micropollutants because these are being released continuously into the environment. Many of these compounds are considered emerging contaminants. These analytes are generally compounds that are not covered by the existing regulations and are now detected more frequently in different environmental compartments. Pharmaceuticals, surfactants, personal care products and other chemicals are considered micropollutants. These compounds must be monitored because, although they are detected in low concentrations, they might be harmful toward ecosystems.

Analytical methodologies for the determination of endocrine disrupting compounds in biological and environmental samples

Endocrine-disruptor compounds (EDCs) can mimic natural hormones and produce adverse effects in the endocrine functions by interacting with estrogen receptors. EDCs include both natural and synthetic chemicals, such as hormones, personal care products, surfactants, and flame retardants, among others. EDCs are characterised by their ubiquitous presence at trace-level concentrations and their wide diversity. Since the discovery of the adverse effects of these pollutants on wildlife and human health, analytical methods have been developed for their qualitative and quantitative determination. In particular, mass-based analytical methods show excellent sensitivity and precision for their quantification. This paper reviews recently published analytical methodologies for the sample preparation and for the determination of these compounds in different environmental and biological matrices by liquid chromatography coupled with mass spectrometry. The various sample preparation techniques are compared and discussed. In addition, recent developments and advances in this field are presented.

New Developments in Liquid Chromatography Mass Spectrometry for the Determination of Micropollutants

The combination of liquid chromatography (LC) with mass spectrometry (MS) in the environmental field has appeared as a valuable tool for the determination of micropollutants. Several groups of compounds have been considered as particularly relevant (e.g., pharmaceuticals, hormones and other endocrine-disrupting, personal care products and their metabolites, flame retardants, surfactants, and plasticizers, among others) since the same ones are continuously being released in the environment mainly as a result of the manufacturing processes, the disposal of unused or expired products, and the excreta. Because these micropollutants are not completely removed in the environment, very specific and sensitive analytical procedures are needed for their identification and quantification. High performance liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) (or LC-MS2) and especially time-of-flight mass spectrometry (TOF/MS), has allowed that many environmental contaminants that are highly polar or nonvolatile or have a high molecular weight to be analyzed or identified. In this work we present an overview focused on the developments of liquid chromatography mass spectrometry applied to the analysis of the main classes of micropollutants in aqueous and solid environmental samples. Various aspects of methodologies based on these techniques, including sample preparation (extraction/preconcentration) and matrix effects, are discussed.

Determination of preservative and antimicrobial compounds in fish from Manila Bay, Philippines using ultra high performance liquid chromatography tandem mass spectrometry, and assessment of human dietary exposure

Ultra high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) determination of four paraben preservatives (methyl, ethyl, propyl and butyl) and two antimicrobial agents (triclosan and triclocarban) belonging to personal care products (PCPs) in 20 species of fish from Manila Bay (Philippines) was performed. Detection of PCPs with greater frequency indicates the ubiquitous contamination of Manila Bay. Concentrations of total paraben were one order of magnitude higher than the antimicrobials in almost all fish, except in Stolephorus indicus and Leiognathus equulus. A positive correlation was observed between parabens concentration and fish length (r = 0.31-0.49; p<0.05 to <0.001) and fish weight (r = 0.28-0.49; p<0.05 to <0.001), but not for the antimicrobials. The estimated dietary exposure values of the four parabens in the Philippines through fish is four orders of magnitude lower than the acceptable daily intake (ADI) of 10mg/kg/day, but the values of antimicrobials are just half of the ADI of TCS. To our knowledge, this is the first report of PCPs contamination in fish from Philippines.

Development of a dispersive liquid-liquid microextraction method for iron speciation and determination in different water samples

A novel, simple and efficient method for the iron (Fe) speciation and determination in different water samples was developed using dispersive liquid-liquid microextraction (DLLME) technique followed by spectrophotometric analysis. The procedure is based on complexation of Fe(II) with O-phenanthroline (O-Phen), the subsequent ion-association formation with picrate anion, then extraction of the complex using DLLME technique. Some important parameters such as the type and volume of extraction and dispersive solvents as well as the extraction time were investigated and optimized in detail. Under the optimum conditions, the calibration graphs were linear over the range of 0.025-1.0 μg mL(-1) with limit of detection of 7.5 μg L(-1). Relative standard deviation for five replicate determinations of Fe at 0.2 μg mL(-1) concentration level was calculated to be 1.2%. Average recoveries for spiked samples were determined to be between 90% and 108%. The method was applied to water samples and parenteral solutions and the amounts of Fe found in these samples using the proposed method were similar with those obtained by a standard method.