Recent applications of microextraction sample preparation techniques in biological samples analysis

Development of a supramolecular solvent-based extraction method for application to quantitative analyses of a wide range of organic contaminants in indoor dust

This study investigates the efficacy of supramolecular solvent (SUPRAS) in extracting a diverse spectrum of organic contaminants from indoor dust. Initially, seven distinct SUPRAS were assessed across nine categories of contaminants to identify the most effective one. A SUPRAS comprising Milli-Q water, tetrahydrofuran, and hexanol in a 70:20:10 ratio, respectively, demonstrated the best extraction performance and was employed for testing a wider array of organic contaminants. Furthermore, we applied the selected SUPRAS for the extraction of organic compounds from the NIST Standard Reference Material (SRM) 2585. In parallel, we performed the extraction of NIST SRM 2585 with conventional extraction methods using hexane:acetone (1:1) for non-polar contaminants and methanol (100%) extraction for polar contaminants. Analysis from two independent laboratories (in Norway and the Czech Republic) demonstrated the viability of SUPRAS for the simultaneous extraction of twelve groups of organic contaminants with a broad range of physico-chemical properties including plastic additives, pesticides, and combustion by-products. However, caution is advised when employing SUPRAS for highly polar contaminants like current-use pesticides or volatile substances like naphthalene.

Liquid-liquid and solid-liquid extractions with low-temperature partitioning - A review

The paper represents the first review of solvent extraction techniques utilizing the low-temperature partitioning/purification (LTP) approach. Initially conceived in the 1960s to purify extracts from fatty matrices, it wasn't until the 2000s that this approach received increasing attention for its efficacy in extracting organic compounds from diverse samples, often without additional cleanup steps. This review covers a brief history and proposes a mechanism for LTP-based solvent extraction. Furthermore, the principal practical issues of the technique are spotlighted, elucidating the factors influencing extraction efficiency. The advantages, limitations, and potential combinations with other extraction techniques of the LTP-based solvent extractions are analyzed. The versatility of the LTP approach is demonstrated by its applications in extracting various compounds from food, environmental, and biological samples, emphasizing its potential for rapid sample preparation with minimal steps, few chemicals, and minimal analyst intervention.

Greenness assessment of microextraction techniques in therapeutic drug monitoring

Aim: In this study, we evaluated the greenness and whiteness scores for microextraction techniques used in therapeutic drug monitoring. Additionally, the cons and pros of each evaluated method and their impacts on the provided scores are also discussed. Materials & methods: The Analytical Greenness Sample Preparation metric tool and white analytical chemistry principles are used for related published works (2007-2023). Results & conclusion: This study provided valuable insights for developing methods based on microextraction techniques with a balance in greenness and whiteness areas. Some methods based on a specific technique recorded higher scores, making them suitable candidates as green analytical approaches, and some others achieved high scores both in green and white areas with a satisfactory balance between principles.

Facile synthesis of amino-functionalized magnetic materials for efficient enrichment of anionic metabolites from biological samples

The analysis of biological samples is often affected by the background matrix. Proper sample preparation is a critical step in the analytical procedure for complex samples. In this study, a simple and efficient enrichment strategy based on Amino-functionalized Polymer-Magnetic MicroParticles (NH₂-PMMPs) with coral-like porous structures was developed to enable the detection of 320 anionic metabolites, providing detailed coverage of phosphorylation metabolism. Among them, 102 polar phosphate metabolites including nucleotides, cyclic nucleotides, sugar nucleotides, phosphate sugars, and phosphates, were enriched and identified from serum, tissues, and cells. Furthermore, the detection of 34 previously unknown polar phosphate metabolites in serum samples demonstrates the advantages of this efficient enrichment method for mass spectrometric analysis. The limit of detections (LODs) were between 0.02 and 4 nmol/L for most anionic metabolites and its high sensitivity enabled the detection of 36 polar anion metabolites from 10 cell equivalent samples. This study has provided a promising tool for the efficient enrichment and analysis of anionic metabolites in biological samples with high sensitivity and broad coverage, facilitating the knowledge of the phosphorylation processes of life.

Dispersive liquid-liquid microextraction and Monte Carlo simulation of margin of safety for octocrylene, EHMC, 2ES, and homosalate in sunscreens

Dispersive liquid-liquid microextraction (DLLME) using a floating organic drop has been optimized and used for the sample preparation of four commonly used ultraviolet filter (UVF) substances in sunscreens. Plackett-Burman experimental design was used to screen 10 variables in DLLME. The most significant variables were then optimized by using a response surface method with a Box-Behnken design. DLLME followed by an optimized HPLC identified octocrylene, 2-ethylhexyl-4-methoxycinnamate, ethylhexyl salicylate, and homosalate as the frequently found UVFs in commercial sunscreens. The systemic exposure dosage and margin of safety (MoS) for the identified UVFs were estimated using in-use concentrations and application patterns. The average systemic exposure dosage values for octocrylene, 2-ethylhexyl-4-methoxycinnamate, ethylhexyl salicylate, and homosalate were 0.52, 0.61, 0.020, and 0.079 mg/kg body weight per day, respectively. Whereas the average MoS values for individual UVFs ranging from 296 to 3160 were all significantly higher than the limit value of 100, the combined exposure risks were slightly above the limit. The probabilistic health risk assessment using Monte Carlo simulation revealed that the combined MoS values were (mean, 10‰, 90‰) 342, 119, and 441, respectively. Regarding the usage of sunscreen cosmetics containing the UVFs studied, these results indicate a safety concern for those who apply multiple UVF products.

Liquid-phase microextraction of aromatic amines: hollow fiber-liquid-phase microextraction and parallel artificial liquid membrane extraction comparison

Aromatic amines (AA) are carcinogenic compounds that can enter the human body through many sources, one of the most important being tobacco smoke. They are excreted with the urine, from which they can be extracted and measured. To that end, hollow fiber-liquid-phase microextraction (HF-LPME) and parallel artificial liquid membrane extraction (PALME) were optimized for the analysis of representative aromatic amines, as alternatives to liquid-liquid extraction (LLE). Relevant extraction parameters, namely organic solvent, extraction time, agitation speed, and acceptor solution pH, were studied, and the two optimized techniques-HF-LPME: dihexyl ether, 45 min, 250 rpm, and pH 1; PALME: undecane, 20 min, 250 rpm and pH 1-were compared. Comparison of the optimized methods showed that significantly higher recoveries could be obtained with PALME than with HF-LPME. Therefore, PALME was further validated. The results were successful for nine different AA, with regression coefficients (R2) of at least 0.991, limits of detection (LOD) of 45-75 ng/L, and repeatability and peak area relative standard deviations (RSD) below 20%. Furthermore, two urine samples from smokers were measured as proof of concept, and 2-methylaniline was successfully quantified in one of them. These results show that PALME is a great green alternative to LLE. Not only does it use much smaller volumes of toxic organic solvents, and sample-enabling the study of samples with limited available volumes-but it is also less time consuming and labor intensive, and it can be automated.

A Fusion of Molecular Imprinting Technology and Siloxane Chemistry: A Way to Advanced Hybrid Nanomaterials

Molecular imprinting technology is a well-known strategy to synthesize materials with a predetermined specificity. For fifty years, the "classical" approach assumed the creation of "memory sites" in the organic polymer matrix by a template molecule that interacts with the functional monomer prior to the polymerization and template removal. However, the phenomenon of a material's "memory" provided by the "footprint" of the chemical entity was first observed on silica-based materials nearly a century ago. Through the years, molecular imprinting technology has attracted the attention of many scientists. Different forms of molecularly imprinted materials, even on the nanoscale, were elaborated, predominantly using organic polymers to induce the "memory". This field has expanded quickly in recent years, providing versatile tools for the separation or detection of numerous chemical compounds or even macromolecules. In this review, we would like to emphasize the role of the molecular imprinting process in the formation of highly specific siloxane-based nanomaterials. The distinct chemistry of siloxanes provides an opportunity for the facile functionalization of the surfaces of nanomaterials, enabling us to introduce additional properties and providing a way for vast applications such as detectors or separators. It also allows for catalyzing chemical reactions providing microreactors to facilitate organic synthesis. Finally, it determines the properties of siloxanes such as biocompatibility, which opens the way to applications in drug delivery and nanomedicine. Thus, a brief outlook on the chemistry of siloxanes prior to the discussion of the current state of the art of siloxane-based imprinted nanomaterials will be provided. Those aspects will be presented in the context of practical applications in various areas of chemistry and medicine. Finally, a brief outlook of future perspectives for the field will be pointed out.

Recent molecularly imprinted polymers applications in bioanalysis

Molecular imprinted polymers (MIPs) as extraordinary compounds with unique features have presented a wide range of applications and benefits to researchers. In particular when used as a sorbent in sample preparation methods for the analysis of biological samples and complex matrices. Its application in the extraction of medicinal species has attracted much attention and a growing interest. This review focus on articles and research that deals with the application of MIPs in the analysis of components such as biomarkers, drugs, hormones, blockers and inhibitors, especially in biological matrices. The studies based on MIP applications in bioanalysis and the deployment of MIPs in high-throughput settings and optimization of extraction methods are presented. A review of more than 200 articles and research works clearly shows that the superiority of MIP techniques lies in high accuracy, reproducibility, sensitivity, speed and cost effectiveness which make them suitable for clinical usage. Furthermore, this review present MIP-based extraction techniques and MIP-biosensors which are categorized on their classes based on common properties of target components. Extraction methods, studied sample matrices, target analytes, analytical techniques and their results for each study are described. Investigations indicate satisfactory results using MIP-based bioanalysis. According to the increasing number of studies on method development over the last decade, the use of MIPs in bioanalysis is growing and will further expand the scope of MIP applications for less studied samples and analytes.

CYP2C9 Polymorphism Influence in PK/PD Model of Naproxen and 6-O-Desmethylnaproxen in Oral Fluid

Polymorphisms in CYP2C9 can significantly interfere with the pharmacokinetic (PK) and pharmacodynamic (PD) parameters of nonsteroidal anti-inflammatory drugs (NSAIDs), including naproxen. The present research aimed to study the PK/PD parameters of naproxen and its metabolite, 6-O-desmethylnaproxen, associated with allelic variations of CYP2C9. In our study, a rapid, selective, and sensitive Liquid Chromatography-Tandem Mass Spectrometry (LC-MS/MS) method was developed and validated for the determination of naproxen and its main metabolite, 6-O-desmethylnaproxen, in oral fluid. Naproxen and its main metabolite were separated using a Shim-Pack XR-ODS 75L × 2.0 column and C18 pre-column at 40 °C using a mixture of methanol and 10 mM ammonium acetate (70:30, v/v), with an injection flow of 0.3 mL/min. The total analytical run time was 3 min. The volunteers, previously genotyped for CYP2C9 (16 ancestral—CYP2C9 *1 and 12 with the presence of polymorphism—CYP2C9 *2 or *3), had their oral fluids collected sequentially before and after taking a naproxen tablet (500 mg) at the following times: 0.25, 0.5, 0.75, 1, 1.5, 2, 3, 4, 5, 6 8, 11, 24, 48, 72 and 96 h. Significant differences in the PK parameters (* p < 0.05) of naproxen in the oral fluid were: Vd/F (L): 98.86 (55.58−322.07) and 380.22 (261.84−1097.99); Kel (1/h): 0.84 (0.69−1.34) and 1.86 (1.09−4.06), in ancestral and mutated CYP2C9 *2 and/or *3, respectively. For 6-O-desmethylnaproxen, no PK parameters were significantly different between groups. The analysis of prostaglandin E2 (PGE2) proved to be effective and sensitive for PD parameters analysis and showed higher levels in the mutated group (p < 0.05). Both naproxen and its main metabolite, 6-O-desmethylnaproxen, and PGE2 in oral fluid can be effectively quantified using LC-MS/MS after a 500 mg oral dose of naproxen. Our method proved to be effective and sensitive to determine the lower limit of quantification of naproxen and its metabolite, 6-O-desmethylnaproxen, in oral fluid (2.4 ng/mL). All validation data, such as accuracy, precision, and repeatability intra- and inter-assay, were less than 15%. Allelic variations of CYP2C9 may be considered relevant in the PK of naproxen and its main metabolite, 6-O-desmethylnaproxen.