An overview of preconcentration techniques combined with inductively coupled plasma mass spectrometry for trace element determination in biological studies.

In the last decades, the determination of trace elements in biological materials has emerged as an important area of study because of its relevance to human health and the environment. Inductively coupled plasma mass spectrometry (ICP-MS) has proven to be a powerful tool for trace element analysis, owing to its high sensitivity and ability to determine several elements in a single measurement. However, given the complex nature of biological matrices and the presence of elements, most of them at ultratrace levels, it becomes crucial to complement ICP-MS with preconcentration techniques to increase the sensitivity and selectivity of analytical methods. This article presents an exhaustive overview of liquid- and solid-phase preconcentration techniques used in combination with ICP-MS for trace element determination in different biological samples from 2000 to the present. An in-depth discussion of the advances on the application of state-of-the-art solvents and materials in trace element extraction and preconcentration is presented. Special attention is given to different strategies for elemental speciation analysis, employing both chromatographic and non-chromatographic techniques. The role of automation in these methodologies is also described. Finally, future trends and challenges related to this topic are discussed.

Deep eutectic solvents as a green alternative for trace element analysis in food and beverage samples: Recent advances and challenges.

Metals and metalloids have different effects on human health even at trace levels. Some of them are essential for living organisms while others can be toxic. Therefore, the determination of trace elements in food and beverage is highly important to understand their impact in human health. A new generation of solvents named deep eutectic solvents (DES) has emerged as a green alternative for trace element analysis, owing to their low toxicity, biodegradability, and high extraction capacity. In recent years, the application of DES in extraction techniques for trace element analysis in food and beverage samples has increased significantly. This review summarizes recent advances and challenges on the application of DES to develop microextraction techniques useful for the analysis of samples with complex matrices. The importance of the use of biodegradable substances instead of classic organic solvents, which are toxic, volatile, and flammable in methods for elemental analysis with a positive environmental impact is also highlighted. Finally, conclusions and future challenges arising from the use of DES in microextraction techniques are discussed.

Elemental Speciation Analysis in Environmental Studies: Latest Trends and Ecological Impact.

Speciation analysis is a key aspect of modern analytical chemistry, as the toxicity, environmental mobility, and bioavailability of elemental analytes are known to depend strongly on an element's chemical species. Henceforth, great efforts have been made in recent years to develop methods that allow not only the determination of elements as a whole, but also each of its separate species. Environmental analytical chemistry has not ignored this trend, and this review aims to summarize the latest methods and techniques developed with this purpose. From the perspective of each relevant element and highlighting the importance of their speciation analysis, different sample treatment methods are introduced and described, with the spotlight on the use of modern nanomaterials and novel solvents in solid phase and liquid-liquid microextractions. In addition, an in-depth discussion of instrumental techniques aimed both at the separation and quantification of metal and metalloid species is presented, ranging from chromatographic separations to electro-chemical speciation analysis. Special emphasis is made throughout this work on the greenness of these developments, considering their alignment with the precepts of the Green Chemistry concept and critically reviewing their environmental impact.

Ultra-sensitive Sb speciation analysis in water samples by magnetic ionic liquid dispersive liquid-liquid microextraction and multivariate optimization.

Efficient separation and preconcentration of inorganic Sb species in different water samples were performed in this work by a novel dispersive liquid-liquid microextraction (DLLME) method based on the application of a magnetic ionic liquid (MIL) and electrothermal atomic absorption spectroscopy (ETAAS) detection. The Sb(iii) species was selectively extracted by complexation with ammonium diethyldithiophosphate (DDTP) and 45 µL of the MIL trihexyl(tetradecyl)phosphonium tetrachloroferrate ([P6,6,6,14]FeCl4) as extractant. Subsequently, a magnetic rod was applied for phase separation, introducing it directly into the sample solution, and the MIL phase was then diluted in chloroform. Afterwards, 15 µL of this solution was injected into the graphite furnace of ETAAS for Sb determination. A multivariate study was performed to obtain the optimal extraction conditions. Selective reduction of Sb(v) to Sb(iii) with 1% (w/v) KI before preconcentration was applied for total inorganic Sb determination and Sb(v) concentration was calculated by subtraction. The analytical performance of the method included extraction efficiencies of 98.0% for Sb(iii) and 92.6% for Sb(v), LOD of 0.02 µg L-1 for Sb(iii) and relative standard deviations of 3.1% for Sb(iii) and 3.5% for Sb(v) (at 6 µg L-1 Sb(iii) and Sb(v), n = 10). The calibration linear range was 0.08-20 µg L-1. The results showed that the proposed methodology was highly sensitive and selective for Sb speciation analysis in tap, dam, mineral, wetland, underground, rain and river water samples.