Preconcentration and speciation analysis of mercury: 3D printed metal scavenger-based solid-phase extraction followed by analysis with inductively coupled plasma mass spectrometry

Switchable metal extractant integrated miniaturized 3D-printed device: A semi-online multi-metal separation system for matrix-free ICP-MS analysis

BACKGROUND

This study tackles the critical challenges in metal analysis by presenting an innovative miniaturized metal extraction device prototype. This device features a functional nanocomposite (FNC) enhanced 3D-printed polylactic acid (PLA) metal extractant (FNC@3D PLA). The research is motivated by the constraints of traditional solid-phase extraction (SPE) methods, specifically their limitations in handling competitive metal ion environments and matrix interference during inductively coupled plasma mass spectrometry (ICP-MS) analysis. The designed prototype aims to overcome these challenges and enhance the extraction efficiency of diverse metals.

RESULTS

The FNC, designed to incorporate various functional groups critical for metal ion extraction efficiency, was meticulously engineered through the reaction of acid-treated and delaminated graphitic carbon nitride nanosheets (Thiol-gCN NSs) with 3-mercaptopropyl trimethoxysilane (MPTMS). The competitive metal ion extraction efficiency of FNC@3D PLA was demonstrated, showcasing notable limit of detection values of 3.2 ± 0.7 ng mL-1 and 8.57 ± 3.05 ng mL-1 for Cu and Ag, respectively. Furthermore, the miniaturized 3D-printed metal-preconcentration setup incorporating FNC@3D PLA exhibited favorable intraday relative standard deviation (RSD) percentage (%) values ranging from 1.23 to 8.6 for both Cu and Ag. Interday RSD % between 1.41 and 8.14 were observed under spiked real urine sample conditions. The sustainability and robustness of the proposed approach were underscored by substantial recovery % values exhibited by FNC@3D PLA, even after eight consecutive regeneration processes.

SIGNIFICANCE

This study significantly contributes to the advancement of analytical methodologies by providing a reliable and efficient platform for metal extraction and preconcentration in practical metal analysis applications. Developed FNC@3D PLA system demonstrates its potential to address the challenges associated with SPE in metal analysis, especially in complex sample matrices. We believe implications of this research can be extended to various fields, from environmental monitoring to clinical diagnostics, where accurate and reliable metal analysis is paramount.

Arithmetic vs. Weighted Means in Fish Fillets Mercury Analyses

Mercury (Hg) analyses in species of fish are performed for two reasons: (1) to safeguard human health; and (2) to assess environmental quality, since different environmental changes may increase the Hg concentrations in fish. These analyses are important since both natural and human activities can increase these Hg concentrations, which can vary extensively, depending on the species, age and catching location. Hg-contaminated fish or other marine foodstuffs can be only detected by chemical analysis. If the aim of Hg analysis is to protect the health of marine food consumers, researcher workers must consider the location where the fish were caught and interpret the results accordingly. Health and environmental officials must appreciate that in specific places, local people may have a daily diet consisting entirely of fish or other marine foods, and these individuals should not be exposed to high concentrations of Hg. Regional and national health and environmental officials should follow the recent guidance of international organizations when drawing their final conclusions about whether the products are safe or unsafe to eat. Correct statistical calculations are not always carried out; so, too high Hg amounts could be presented, and fish eaters could be protected. This work has been conducted to show the differences in Hg concentrations between weighted (weighted with fish weights) and arithmetic means. Thus, the mean that is only weighted also includes the Hg content in fishes; so, the exposure to Hg can be evaluated.

Highly sensitive and selective fluorescent "turn-on" sensor for Ag+ detection using MAPbBr3@PCN-221(Fe): An efficient Ag+-bridged energy transfer from perovskite to MOF

Metal ion-induced water pollution is attracting increasing public attention. Perovskite quantum dots and metal-organic frameworks (MOFs), owing to their outstanding properties, hold promise as ideal probes for detecting metal ions. In this study, a composite material, MAPbBr3@PCN-221(Fe), was prepared by encapsulating MAPbBr3 quantum dots with PCN-221(Fe), demonstrating high chemical stability and good reusability. The composite material shows a sensitive fluorescence turn-on signal in the presence of silver ions. The fluorescence intensity of the composite material exhibits a linear relationship with the concentration of Ag+ in the solution, with a low detection limit of 8.68 µM. Moreover, the fluorescence signal exhibits a strong selectivity for Ag+, enabling the detection of Ag+ concentration. This fluorescence turn-on signal originates from the Ag+-bridged energy transfer from the conductive band of MAPbBr3 to the excited state of the MOF, which is directly proportional to the concentration of silver ions. Simultaneously, this finding may open up a new possibility in artificial controlled energy transfer from perovskite to MOF for future development.

Application of three-dimensional printing technology in environmental analysis: A review

The development of environmental analysis devices with high performance is essential to assess the potential risks of environmental pollutants. However, it is still challenging to develop environmental analysis equipment with miniaturization, portability, and high sensitivity based on traditional processing techniques. In recent years, the popularity of 3D printing technology (3DP) with high precision, low cost, and unlimited design freedom has provided opportunities to solve the existing challenges of environmental analysis. 3D printing has brought solutions to promote the high performance and versatility of environmental analysis equipment by optimizing printing materials, enhancing equipment structure, and integrating multidisciplinary technology. In this paper, we comprehensively review the latest progress in 3D printing in various aspects of environmental analysis procedures, including but not limited to sample collection, pretreatment, separation, and detection. We highlight their advantages and challenges in determining various environmental contaminants through passive sampling, solid-phase extraction, chromatographic separation, and mass spectrometry detection. The manufacturing of 3D-printed environmental analysis devices is also discussed. Finally, we look forward to their development prospects and challenges.

TiO2 nanoparticle-Coated 3D-Printed porous monoliths enabling highly sensitive speciation of inorganic Cr, As, and Se

Post-printing functionalization can enhance the functionality and applicability of analytical devices manufactured using three-dimensional printing (3DP) technologies. In this study we developed a post-printing foaming-assisted coating scheme-through respective treatments with a formic acid (30%, v/v) solution and a sodium bicarbonate (0.5%, w/v) solution incorporating titanium dioxide nanoparticles (TiO2 NPs; 1.0%, w/v)-for in situ fabrication of TiO2 NP-coated porous polyamide monoliths in 3D-printed solid phase extraction columns, thereby enhancing the extraction efficiencies of Cr(III), Cr(VI), As(III), As(V), Se(IV), and Se(VI) for speciation of inorganic Cr, As, and Se species in high-salt-content samples when using inductively coupled plasma mass spectrometry. After optimizing the experimental conditions, the 3D-printed solid phase extraction columns with the TiO2 NP-coated porous monoliths extracted these species with 5.0- to 21.9-fold enhancements, relative to those obtained with the uncoated monolith, with absolute extraction efficiencies ranging from 84.5 to 98.3% and method detection limits ranging from 0.7 to 32.3 ng L-1. We validated the reliability of this multi-elemental speciation method through determination of these species in four reference materials [CASS-4 (nearshore seawater), SLRS-5 (river water), 1643f (fresh water), and Seronorm Trace Elements Urine L-2 (human urine); relative errors between certified and measured concentrations: 5.6 to +4.0%] and spike analyses of seawater, river water, agriculture waste, and human urine samples (spike recoveries: 96-104%; relative standard deviations of these measured concentrations all below 4.3%). Our results demonstrate that post-printing functionalization has great potential for future applicability in 3DP-enabling analytical methods.