Solvent Precipitation Research Articles

Selective recovery of yttrium oxide and yttrium–europium oxide particles from fluorescent wastes by solvent extraction, precipitation, and calcination

Selective recovery of yttrium oxide and yttrium–europium oxide particles from fluorescent wastes by solvent extraction, precipitation, and calcination

Preparation of structural colors from lignin: Improving the homogeneity between different raw materials by solvent precipitation fractionation

Structural color materials prepared by lignin colloidal spheres (LCSs) have attracted great interest due to their biocompatibility, biodegradability, multifunctionality, and ability to weaken incoherent scattering. However, the lignin raw materials originating from different biomass resources have distinct heterogeneity leading to a big difference in the size of resultant LCSs via self-assembly, which is a major challenge for the preparation of stable structural colors. In this work, we employ the solvent precipitation method to fractionate the crude lignin samples obtained from corncob, softwood, hardwood, and bamboo, respectively. After solvent precipitation fractionation, the self-assembly behaviors of different lignin samples become similar. The LCSs prepared by fractionated lignin samples show quite similar sizes (212, 202, 215, and 210 nm) compared with the LCSs prepared by crude lignin samples (341, 83, 128, and 253 nm). The quantitative atomic force microscope force spectroscopy demonstrates the improved homogeneity of LCSs prepared by fractionated lignin samples is attributed to similar long-ranged intermolecular forces in self-assembly. By employing LCSs as building blocks, the lignin-based pigments with stable structural colors are successfully prepared. The presented colors are independent of the biomass resource types, which benefits the product stability and large-scale production of lignin-based structural color materials.

Antioxidant and anticancer activities on HT-29 colon cancer cells of protein isolate extracted from Cordyceps militaris fruiting body using diverse isolation methods

The present research examines different techniques for isolating proteins from Cordyceps militaris fruiting body powder (COR), namely ammonium sulfate precipitation (ASP), organic solvent precipitation (OSP), and isoelectric precipitation (IEP). ASP yielded the highest protein content (78.90 %), effectively concentrating proteins, while OSP and IEP also produced substantial yields (57.41 % and 69.06 %, respectively). Color analysis revealed differences among isolates, with ASP resulting in a darker hue. ASP and IEP showed higher red and yellow components, respectively. Essential amino acid content was significantly higher in ASP isolate compared to COR, indicating effective amino acid concentration. Thermal analysis revealed different decomposition temperatures and enthalpy values among isolates. OSP displayed the highest phenolic content, while IEP exhibited the highest flavonoid content. Antioxidant assays showed ASP to have the highest DPPH-RSA and ABTS-RSA, while IEP showed the highest FRAP value. ASP demonstrated anticancer activity against HT-29 colon cancer cells inducing cell death apoptosis and inhibiting cell migration, with an IC50 of 360.63 µg/mL, comparable to Paclitaxel. These findings suggest that Cordyceps militaris protein isolate, particularly from ASP, has significant antioxidant and anticancer potential, supporting its potential as a natural alternative to synthetic drugs with fewer side effects.

The emulsifying capacity and stability of potato proteins and peptides: A comprehensive review.

The potato has recently attracted more attention as a promising protein source. Potato proteins are commonly extracted from potato fruit juice, a byproduct of starch production. Potato proteins are characterized by superior techno-functional properties, such as water solubility, gel-forming, emulsifying, and foaming properties. However, commercially isolated potato proteins are often denatured, leading to a loss of these functionalities. Extensive research has explored the influence of different conditions and techniques on the emulsifying capacity and stability of potato proteins. However, there has been no comprehensive review of this topic yet. This paper aims to provide an in-depth overview of current research progress on the emulsifying capacity and stability of potato proteins and peptides, discussing research challenges and future perspectives. This paper discusses genetic diversity in potato proteins and various methods for extracting proteins from potatoes, including thermal and acid precipitation, salt precipitation, organic solvent precipitation, carboxymethyl cellulose complexation, chromatography, and membrane technology. It also covers enzymatic hydrolysis for producing potato-derived peptides and methods for identifying potato protein-derived emulsifying peptides. Furthermore, it reviews the influence of factors, such as physicochemical properties, environmental conditions, and food-processing techniques on the emulsifying capacity and stability of potato proteins and their derived peptides. Finally, it highlights chemical modifications, such as acylation, succinylation, phosphorylation, and glycation to enhance emulsifying capacity and stability. This review provides insight into future research directions for utilizing potato proteins as sustainable protein sources and high-value food emulsifiers, thereby contributing to adding value to the potato processing industry.

A recoverable hydrophilic deep eutectic solvent for efficient extraction of polyphenolic compounds from raspberry root.

Green deep eutectic solvents (DESs) are widely used to extract bioactive components from plant biomass; however, hydrophilic DES and bioactive component isolation methods have not been developed. In this study, we synthesized hydrophilic DES (CL-CA-DES) using citric acid and choline chloride. We combined this with environmentally friendly anion- and cation-exchange resin column chromatographic isolation methods. This approach extracted and isolated four polyphenolic compounds (catechins, epicatechins, procyanidin B1, and procyanidin B2) from raspberry root and efficiently recovered the hydrophilic DES. CL-CA-DES extracted significantly higher contents of catechin and procyanidin B2 from raspberry root compared to other solvents. It also extracted substantially higher contents of epicatechin compared to butyl alcohol, 70% ethanol, and water, but there was no significant difference when compared with acetone and ethyl acetate. Additionally, CL-CA-DES extracted significantly higher contents of procyanidin B1 compared to butyl alcohol, water, and ethyl acetate, with no significant difference when compared with 70% ethanol and acetone. The isolation efficiency of the bioactive components in the raspberry root extract by anion- and cation-exchange resin column chromatography was higher than that of the organic solvent extraction and precipitation generation methods, and the method was effective in recovering CL-CA-DES with a recovery rate higher than 60%. In conclusion, this study developed a new method for the efficient recovery of hydrophilic CL-CA-DES, which can be used for isolating polyphenolic compounds from raspberry root.

Differences in Protein Capture by SP3 and SP4 Demonstrate Mechanistic Insights of Proteomics Cleanup Techniques.

The goal of proteomics experiments is to identify proteins to observe changes in cellular processes and diseases. One challenge in proteomics is the removal of contaminants following protein extraction, which can limit protein identifications. Single-pot, solid-phase-enhanced sample preparation (SP3) is a cleanup technique in which proteins are captured on carboxylate-modified particles through a proposed hydrophilic-interaction-liquid-chromatography (HILIC)-like mechanism. Recent results have suggested that proteins are captured in SP3 due to a protein-aggregation mechanism. Solvent precipitation, single-pot, solid-phase-enhanced sample preparation (SP4) is a newer cleanup technique that employs protein aggregation to capture proteins without modified particles. We hypothesize that differences in capture mechanisms of SP3 and SP4 affect which proteins are identified by each cleanup technique. Herein, we assess the proteins identified and enriched using SP3 versus SP4 for MCF7 subcellular fractions and correlate protein capture in each method to protein hydrophobicity. Our results indicate that SP3 captures more hydrophilic proteins through a combination of HILIC-like and protein-aggregation mechanisms, while SP4 captures more hydrophobic proteins through a protein-aggregation mechanism. Ultimately, we demonstrate that protein-capture mechanisms are distinct, and the selection of a cleanup technique that yields high proteome coverage is dependent on protein-sample hydrophobicity. Data has been deposited into MassIVE (MSV000094130) and ProteomeXchange (PXD049965).

Preparation of polystyrene microplastic particles by solvent-dissolution-precipitation

The reliable characterisation of the physicochemical properties of micro-sized plastic particles requires quality reference materials for establishing, calibrating, and validating methods. Heterogeneity in particle size, shape and surface chemistry are important factors for reference materials for them to mimic environmental microplastics. This paper introduces a method for preparing model polystyrene micro and nano plastic reference materials using a solvent dissolution-precipitation approach. Polystyrene microplastic particles with mean particle sizes of 0.35, 15.7, 30.0 and 52.3 micron were produced using solvent precipitation under different synthesis conditions with the particle present in a well dispersed and partially dispersed system. The particle size can be controlled by reducing the initial polystyrene-cyclohexane concentration and adjusting the volume of methanol. At a fixed polystyrene-cyclohexane ratio, particles within the specified size range were consistently produced. Chemical analysis using pyrolysis-gas chromatography-mass spectrometry revealed that synthesized microplastics maintain their chemical properties, aligning with the original composition of virgin polystyrene pellets. A similar conclusion was drawn after examining the surface chemistry of the virgin and synthesised microplastic particles using ATR-FTIR analysis. The polystyrene particles produced in this way may be of use as reference materials and might be of interest for toxicological studies.

Thiolated eudragit/β-cyclodextrin/centella asiatica nanomaterial for bone tissue engineering construct

Polymeric scaffolds and nanomaterials enriched with herbal extracts have been extensively studied for bone tissue regeneration due to their well-organized targeting ability and site-specific action at the intended locus. The use of polymer hybrids functionalized with plant extract in developing bone-specific material is a significant approach. Therefore, the current study aimed to develop a nanomaterial using a combination of thiolated eudragit, β-cyclodextrin, and Centella Asiatica to promote bone tissue regeneration. Initially, a composite material was developed by freeze-thawing technique and subsequently, the composite was developed into a nanocomposite by combining ionic gelation and solvent precipitation techniques. The nanocomposite was characterized by dynamic light scattering, scanning electron microscopy, atomic force microscopy, XRD, and FTIR studies. To assess the cytotoxicity and cell differentiation efficiency of the composite, in vitro cell line studies such as MTT assay and cell proliferation studies were performed using MG 63 (human bone fibroblasts) cell lines. In silico studies were conducted to investigate the bone-targeting efficacy of the developed nanocomposite. The results of FTIR and XRD analysis confirmed the successful thiolation of eudragit. SEM analysis of the composite showed a porous structure with an average pore diameter of 1 μm. DLS and AFM characterization indicated the zeta potential value of −37.06 mV and the average size of the nanocomposite was within 100–300 nm. The gel fraction and swelling degree of the developed nanocomposite were observed to be 80.08 ± 4.47% and 2.313 ± 0.04 respectively. Viscosity was determined to be 133.6 ± 26.008 cps. Optical profilometry data of the composite indicated mean roughness (Ra) and root mean square roughness (Rq) of 4.727 μm and 6.075 μm respectively. MTT assay inferred the cytotoxic nature and tolerance of the nanoparticles against the MG-63 cell lines. Cell proliferation studies on the MG-63 cell line exhibited a characteristic growth with the developed nanoparticles. In vitro studies in corroboration with the in silico method of molecular docking confirmed that the composite has the bone targeting efficacy and the osteogenic property where it plays a key role in the isoprenoid biosynthetic pathway by being the inhibitor of Farnesyl diphosphate synthase (FDPS) which in turn results in bone tissue regeneration.

Optimized LC-MS/MS methods for quantifying antibody-drug conjugate payloads in cell culture media containing phenol red.

Aim: Phenol red is commonly used in cell culture media, but can be detrimental to bioanalysis of in vitro samples as it may impact instrument reliability. Many researchers do their final stage of culture in 'phenol red free' media, but in collaborative work this is not always feasible.Materials & methods: A comparison was made between typical extraction methods to reduce phenol red matrix interferences, including organic solvent precipitation and solid phase extraction.Results: The final method was demonstrated to be precise and accurate for the measurement of a target analyte by LC-MS/MS, and was applied to an in vitro ADC deconjugation study.Conclusion: This method allows for for continued bioanalytical support of in vitro models used in drug development.

Protein from tiger nut meal extracted by deep eutectic solvent and alkali-soluble acid precipitation: A comparative study on structure, function, and nutrition

Protein from tiger nut meal (TNP) performance high nutritional value. This study optimized the extraction parameters for TNP (DES-TNP) using deep eutectic solvent, with HBD: HBA = 5:1, Liquid: Solid = 11:1, and the moisture content was 15 %. A comprehensive comparison was conducted with the protein extracted using alkali-soluble acid precipitation (ASAE-TNP). DES-TNP demonstrated significantly higher purity (76.21 ± 2.59 %) than ASAE-TNP (67.48 ± 1.11 %). Density functional theory confirmed the successful synthesis of DES and its strong interaction with TNP. Moreover, DES-TNP and ASAE-TNP were different in structure (microscopic, secondary, and tertiary) and molecular weight distribution. The discrepancy contributed to the different functional properties, DES-TNP exhibiting better solubility, emulsification and foaming properties at pH13 compared to ASAE-TNP. For nutritional properties, DES-TNP and ASAE-TNP exhibited similar amino acid composition and digestibility, but the total amino acid content of DES-TNP was higher. This study presented a novel method for the extraction and comprehensive utilization of TNP.

Utilizing Recycled Expanded Polystyrene Plastics to Stabilize Metal–Organic Frameworks for Heterogeneous Catalysis

Polystyrene plastics present significant environmental and human health threats due to their poor recyclability and degradability. However, leveraging their properties to enhance material performance stands out as one of the most effective strategies for mitigating these issues. Here, we have employed recycled expanded polystyrene plastics to manufacture metal–organic framework/expanded polystyrene plastic composites (MOF@EPP) using an adverse solvent precipitation method. This method simultaneously recycles EPPs and safeguards moisture-sensitive MOFs. Due to the exceptional hydrophobic properties of EPPs, HKUST−1@EPP can maintain structural integrity even when immersed in water for 30 days. This method is applicable to other moisture-sensitive MOFs, such as MOF−74(Zn) and MIL−53(Al). The HKUST−1@EPP composite also exhibits desirable heterogeneous catalytic activity in the Knoevenagel condensation reaction between benzaldehyde and acrylonitrile. The conversion rate can reach 94.9% within 4 h at 90 °C and does not exhibit a significant decrease even after six cycles, even in the presence of water. This study not only introduces a novel concept for recycling polystyrene plastics, but also offers a practical strategy for safeguarding moisture-sensitive MOFs.

Hydroxypropyl methylcellulose/sodium alginate/hydroxyapatite nano biomaterial enriched with zinc to promote bone tissue augmentation

Bone is a dynamic connective tissue that provides structural support and locomotion to human physiology. Severe bone degeneration can occur in cases of trauma, infections, genetic disorders, tumors, and hormonal imbalances. This leads to a demand for scaffolds and composites to enhance bone tissue regeneration. The present study aimed to develop a composite material using hydroxypropyl methylcellulose and sodium alginate in combination with hydroxyapatite. The composite was doped with zinc and developed into a nanocomposite using ionic gelation and solvent precipitation methods. The prepared nanocomposite was characterized by scanning electron microscopy, atomic force microscopy, dynamic light scattering, FTIR, and XRD studies. In vivo pharmacological studies were conducted to establish the bone targeting and bone tissue regeneration efficacy of the developed nanocomposite. The nanocomposite was checked for cell toxicity by performing an MTT assay using MG63 cell line and the molecular mechanism of targeting efficiency was assessed by an in silico evaluation method. The results of the study confirmed the polymeric interlinking in the nanocomposite and the successful preparation of a composite material using biodegradable excipients. SEM and AFM studies indicated that the nanocomposite was within the 80–200 nm size range. MTT assay indicated that the developed nanocomposite was not cytotoxic and well tolerated by the MG63 cell line. In vivo, studies in validation with molecular docking evaluation suggested that the nanocomposite was effectively targeted to the bone and enhanced the bone density by blocking Farnesyl Diphosphate Synthetase (FDPS) in the mevalonate pathway which is essential for inhibiting the osteoclastic activity and promoting osteogenesis.

Innovative pilot-scale process for sustainable rare earth oxide production from coal byproducts: A comprehensive environmental impact assessment

This study developed a pilot-scale process feeding with two different materials resulting from a column leaching process and acid mine drainage (AMD) streams to recover rare earth elements (REEs). A life cycle assessment (LCA) study was done to evaluate the environmental impacts of rare earth production from deleterious material in the form of highly contaminated leachate (HCL) and low-contaminated leachate (LCL). The results indicate that the main contributors to environmental categories that produce RE-hydroxide stages are NaOH and electricity. Also, oxalic acid, Na2CO3, and hydrochloric acid significantly contribute to the production stage of individual rare earth oxides (REOs), including solvent extraction (SX) and precipitation steps. The HCL route has higher environmental impacts than LCL due to higher chemical/energy and H2SO4 usage, so 468 and 292 kg of carbon dioxide are generated to produce 1 t of individual REOs from HCL and LCL routes, respectively. Moreover, the carbon dioxide emitted from the process, including the RE-hydroxide production, SX, and REOs production, is less than 10 t CO2. A sensitivity analysis was also performed to assess the changeability of the environmental footprints of the main inputs in the SX process, as the main stage has a higher contribution to the whole process. This LCA study is the first step toward understanding the environmental influence of new processing methods to produce REEs from coal by-products through a developed pilot-scale process.

High performance polyvinyl alcohol/lignin fibers with excellent mechanical and water resistance properties

To address the shortcoming of Polyvinyl alcohol (PVA) fibers for food or medical packaging materials including low mechanical strength and poor water resistance, lignin (LN) was used as raw material, acetone/H2O as solvent to self-assemble into lignin nanoparticles (LNP) by adverse solvent precipitation approach, and then PVA/LNP composite fibers with different LNP contents were fabricated successfully by wet and dry spinning. Herein, vast hydrophilic hydroxyl groups in PVA decreased owing to the hydrogen bond between LN and PVA, Especially, with only 0.5 wt% loading of LNP into the PVA/LNP fibers, the diameter was 94.4 dtex, tensile strength was 10.1 cN/dtex (1279.8 MPa), initial modulus was 94.7 cN/dtex (12.0 GPa), the crystallinity was 56.7 %, the orientation was 97.1 %, and water contact angle was 103.1°. Compared with pure PVA fibers, the tensile strength of PVA/LNP-0.5 fibers was increased by 44.2 % and the contact angle was increased 37°. This work provides novel insights into obtaining lignin-reinforced PVA composite fibers with strong mechanical properties and excellent water resistance properties, indicating the potential of the PVA/LNP fibers for food or medical packaging application.

Production and characterization of an organic solvent activated protease from haloalkaliphilic bacterium Halobiforma sp. strain BNMIITR

An unusual haloalkaliphilic bacterium known as Halobiforma sp. strain BNMIITR, which was noticed to produce an extracellular alkaline protease, was found in a soil sample from Northern India's Sambhar Lake. On the generation of protease, the effects of dietary elements including nitrogen and carbon sources, amino acids, and growth conditions like temperature and pH were investigated. When low-cost agricultural by-products were employed as nitrogen sources, the manufacturing of enzymes was significantly boosted. In the present study, protease production was enhanced by 2.94 fold and 2.17 fold. By solvent precipitation and Hydrophobic interaction chromatography (HIC) on Phenyl Sepharose 6 Fast Flow matrix, the enzyme was purified 31.67 fold. It was determined that the apparent molecular mass was 21 kDa. The pH range where the enzyme was most stable was 6.0–12.0, with a temperature of 50 °C as optimum. When there was alkaline earth metals and heavy metals, protease was discovered to be active. It was evident that the enzyme was a serine type of protease because it was active in the presence of a variety of surfactants, oxidizing and reducing chemicals, and phenylmethylsulfonyl fluoride (PMSF) completely inhibited activity. Enzyme exhibited a wide range of substrate specificity. Amazingly, enzyme remained stable both in polar and nonpolar solvents. The most interesting aspect of this enzyme is enhanced activity in polar solvents like dimethylformamide (DMF) and dimethyl sulfoxide (DMSO). It was discovered that the protease was stable and compatible with a number of widely available detergents.

Analysis and insights of the second-generation ternary AMP-PZ-MEA solvents for post-combustion carbon capture: Absorption-regeneration performance

This work comprehensively investigates absorption and regeneration performance of the second-generation AMP-PZ-MEA in comparison with the first-generation AMP-PZ-MEA, the benchmark 5 M MEA, and the conventional MEA at the same amine concentration. The performance indicators include CO2 absorption capacity, mass transfer coefficient, CO2 removal percentage, amount of desorbed CO2, initial CO2 desorption rate, and regeneration heat duty. Both 6 M (i.e., 2:2.5:1.5, 1.3:3.2:1.5, and 0.95:3.55:1.5) and 7 M (i.e., 2:2.5:2.5, 1.3:3.2:2.5, and 0.95:3.55:2.5) second-generation blends show more promising overall absorption and regeneration performance than 5 M, 6 M, and 7 M MEA. In comparison with the first-generation blend, 6 M and 7 M second-generation blends deliver more favorable mass transfer rate. Interestingly, an increase of PZ:AMP molar ratio accelerates mass transfer and absorption capacity but unfavorably affects solvent regeneration. Also, high viscosity of the second-generation 7 M blend (especially, at its equilibrium CO2 loading) retards the solvent regeneration. The key success for a formulation of AMP-PZ-MEA is appropriate PZ:AMP molar ratio and total amine concentration. Too high and too low PZ:AMP molar ratio lead to (i) solvent precipitation and (ii) imbalance of absorption and regeneration performance. Three standouts are recommended. 2.5:0.5:3 is attractive due to its low regeneration heat duty (42.1% lower than that of 5 M MEA). In terms of mass transfer coefficient, 0.95:3.55:1.5 shows 148.6% higher than 5 M MEA. 2:2.5:1.5 is also favorable according its high mass transfer coefficient (91.3% greater respecting 5 M MEA) and low regeneration heat duty (16.3% less than 5 M MEA).

Advanced Techniques in the Purification of Lignin: Challenges, Methods, and Industrial ApplicationsA Review

Lignin, a complex and abundant biopolymer found in the cell walls of plants, is gaining significant attention due to its potential applications in various industries, including biofuels, bioplastics, and pharmaceuticals. However, the purification of lignin is a critical challenge due to its heterogeneous structure and the presence of impurities, which can hinder its industrial application. This review provides an overview of the current methods used for lignin purification, including solvent fractionation, membrane filtration, precipitation techniques, and chromatographic methods. It also discusses the characterization techniques employed to assess the purity and properties of lignin, such as Fourier-transform infrared spectroscopy (FTIR), Nuclear Magnetic Resonance (NMR), and Gel Permeation Chromatography (GPC). The review highlights the effectiveness of different purification methods and their impact on the physical, chemical, and thermal properties of lignin. Furthermore, it addresses the challenges and limitations of current purification techniques and suggests potential future directions for research. The findings underscore the importance of developing more sustainable and costeffective purification processes to fully realize the industrial potential of lignin.

Production of High-Purity Alumina by Combining Solvent Extraction and Precipitation Techniques

Production of High-Purity Alumina by Combining Solvent Extraction and Precipitation Techniques

Simultaneous Determination of Two Metabolites of Gelsemium elegans by LC-MS/MS in Rat Urine and its Application to Pharmacokinetic Study

Background: G. elegans is a highly useful medicinal plant with broad and superior clinical pharmacological effects. However, it also exhibits high toxicity to humans, so it must be used with extreme caution in clinical practice. Previous studies on G. elegans have mainly focused on its main ingredients from perspectives of pharmaceutical analysis, pharmacokinetics, and pharmacodynamics. The kinetic behavior of G. elegans' main metabolites in vivo has not yet been reported, which is also crucial for studying the herb's toxification and detoxification process. Aims: This study aimed to establish a quantitative method to describe the metabolic profile of the two main metabolites of koumine after oral administration of G. elegans to rats. Objective: The objective of this study was to test two major metabolites of G. elegans in rat urine after administration using a rapid and sensitive high-performance liquid chromatographic-tandem mass spectrometric (HPLC-MS/MS) method developed in advance. Methods: A Kromasil C18 column was used as the stationary phase for chromatographic separation, with an isocratic mobile phase consisting of mixture of water (2 mM ammonium formate), formic acid, and methanol (25:0.05:75, v/v/v) at a flow rate of 0.40 mL/min. The mass spectrometer was equipped with an electrospray ionization (ESI) source operating in positive ionization mode, and detection was performed using a selective reaction monitoring (SRM) mode. Detection was performed in selective reaction monitoring (SRM) mode. Protein precipitation was used to pretreat the rat urine samples before analysis, with acetonitrile as the precipitation solvent. In this study, a "relative quantification" strategy was employed, which avoided the expensive and time-consuming separation of standard substances. The assay was validated in terms of specificity, linearity, precision, stability, recovery, and other aspects. Results: The intra- and inter-day precision values were less than 12.7%. The recoveries at three different concentrations were all above 73.1%. The stability study showed that the analytes were stable during the experiment. The method was then used to study the kinetic profiles of N-demethylkoumine and N-oxidatekoumine in rat urine for the first time. Conclusion: In this study, the established LC/MS method was fully validated and proven to be sensitive and accurate for the simultaneous determination of the two main metabolites of G. elegans in rats' urine samples. These results could provide references for the safe use of koumine and G. elegans in clinical applications.

Recovery of 400 Chemicals with Three Extraction Methods for Low Volumes of Human Plasma Quantified by Instrumental Analysis and In Vitro Bioassays.

Human biomonitoring studies are important for understanding adverse health outcomes caused by exposure to chemicals. Complex mixtures of chemicals detected in blood - the blood exposome - may serve as proxies for systemic exposure. Ideally, several analytical methods are combined with in vitro bioassays to capture chemical mixtures as diverse as possible. How many and which (bio)analyses can be performed is limited by the sample volume and compatibility of extraction and (bio)analytical methods. We compared the extraction efficacy of three extraction methods using pooled human plasma spiked with >400 organic chemicals. Passive equilibrium sampling (PES) with polydimethylsiloxane (PDMS) followed by solid phase extraction (PES + SPE), SPE alone (SPE), and solvent precipitation (SolvPrec) were compared for chemical recovery in LC-HRMS and GC-HRMS as well as effect recovery in four mammalian cell lines (AhR-CALUX, SH-SY5Y, AREc32, PPARγ-BLA). The mean chemical recoveries were 38% for PES + SPE, 27% for SPE, and 61% for SolvPrec. PES + SPE enhanced the mean chemical recovery compared to SPE, especially for neutral hydrophobic chemicals. PES + SPE and SolvPrec had effect recoveries of 100-200% in all four cell lines, outperforming SPE, which had 30-100% effect recovery. Although SolvPrec has the best chemical recoveries, it does not remove matrix like inorganics or lipids, which might pose problems for some (bio)analytical methods. PES + SPE is the most promising method for sample preparation in human biomonitoring as it combines good recoveries with cleanup, enrichment, and potential for high throughput.