Cloud point extraction utilizable for separation and preconcentration of (ultra)trace elements in biological fluids before their determination by spectrometric methods: a brief review

A Hypothetical Approach to Concentrate Microorganisms from Human Urine Samples Using Paper-Based Adsorbents for Point-of-Care Molecular Assays

This hypothesis demonstrates that the efficiency of loop-mediated isothermal amplification (LAMP) for nucleic acid detection can be positively influenced by the preconcentration of microbial cells onto hydrophobic paper surfaces. The mechanism of this model is based on the high affinity of microbes towards hydrophobic surfaces. Extensive studies have demonstrated that hydrophobic surfaces exhibit enhanced bacterial and fungal adhesion. By exploiting this inherent affinity of hydrophobic paper substrates, the preconcentration approach enables the adherence of a greater number of target cells, resulting in a higher concentration of target templates for amplification directly from urine samples. In contrast to conventional methods, which often involve complex procedures, this approach offers a simpler, cost-effective, and user-friendly alternative. Moreover, the integration of cell adhesion, LAMP amplification, and signal readout within paper origami-based devices can provide a portable, robust, and highly efficient platform for rapid nucleic acid detection. This innovative hypothesis holds significant potential for point-of-care (POC) diagnostics and field surveillance applications. Further research and development in this field will advance the implementation of this technology, contributing to improved healthcare systems and public health outcomes.

Analytical Application of Layered Double Hydroxides as High-Capacity Sorbents in Dispersive Solid Phase Extraction for the Separation and Preconcentration of (Ultra)Trace Heavy Metals

Separation/preconcentration procedures are of great importance in the elemental analysis. In this context, layered double hydroxides (LDH) have emerged as promising sorbents in dispersive solid phase extraction (DSPE) procedures. By optimizing the DSPE procedure, lower limits of detection (LOD) can be achieved, making less sensitive detection methods viable for accurate quantification of the (ultra)trace analytes. This is of significant importance from a financial standpoint, as it enables the utilization of cost-effective and readily available detection methods. The extraction procedures using LDH typically require only a few minutes to complete, with some procedures taking as little as 1.5 min. Many studies have reported techniques that eliminate the need for centrifugation, which results in time savings and reduced sample handling. This is particularly important for ultratrace analysis. However, it has been observed that the use of certified reference materials (CRM) to validate the reliability of the developed extraction procedures is often overlooked. The literature also demonstrates inconsistencies in the terminology and abbreviations employed for extraction procedures, which may cause confusion. LDH, extensively studied for various purposes, offer a wide range of modifications and can form composites with other materials, enhancing their surface characteristics and adsorption performance. The development of novel and effective nanocomposites will undoubtedly be a research objective in this field of analytical chemistry, aiming to advance the reliability of extraction procedures. Moreover, integrating of LDH-based DSPE procedures with appropriate detection methods can enable potential automation and pave the way for online applications.

A Review of Analytical Techniques for the Determination and Separation of Silver Ions and Its Nanoparticles

Many articles have already been published dealing with silver ions and its nanoparticles, but mostly from the environmental and toxicological point of view. This article is a review focused on the various analytical techniques and detection platforms used in the separation and determination of mentioned above species, especially on the trace concentration level. Commonly used are optical methods because of their high sensitivity and easy automation. The separation methods are mainly used for the separation and preconcentration of silver particles. Their combination with other analytical techniques, mainly inductively coupled plasma mass spectrometry (ICP-MS) leads to very low detection limits of analysis. The electrochemical methods are also powerful and perspective mainly because of the fabrication of new sensors designed for silver determination. All methods may be combined with each other to achieve a synergistic improvement of analytical parameters with an impact on sensitivity, selectivity and reliability. The paper comprises a review of all three types of analytical methods on the determination of trace quantities of silver ions and its nanoparticles.

Cloud point extraction associated with differential pulse voltammetry: preconcentration and determination of trace uranyl in natural water

A procedure for the electroanalytical determination of uranyl ions pre-concentrated from natural water by cloud point extraction (CPE) is developed in this study.