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1.
Food Chem ; 462: 140913, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39197241

ABSTRACT

Grape processing generates large amounts of by-products, including seeds rich in hydrophilic and lipophilic antioxidants. This study demonstrates, for the first time, that subjecting grape seeds to a single ultrasound-assisted extraction (UAE) with aqueous ethanolic solutions yields both flavan-3-ols and tocochromanols in the final extract. Notably, the water content in ethanol significantly influences the extractability of tocochromanols more than flavan-3-ols. Solid-to-solvent ratios of 1:50 to 1:2 were tested for both analytical and industrial applications. A sustainable analytical approach for recovering flavan-3-ols and tocochromanols using 60% and 96.4% ethanol extractions was validated and employed to profile nineteen genotypes of lesser-studied interspecific grape crosses (Vitis spp.). Different genotypes showed a wide range of concentrations of tocopherols (1.6-6.3 mg/100 g), tocotrienols (1.0-17.4 mg/100 g), and flavan-3-ols (861-9994 mg/100 g). This indicated that the genetic background and maturity of the plant material are crucial factors from an industrial perspective due to the initial concentration of bioactive compounds. Finally, the study also discussed the fundamental aspects of hydrophobic antioxidant extractability from the lipid matrix with aqueous ethanol solutions and the limitations of the workflow, such as the non-extractable tocochromanols and their esters and the losses of these lipophilic antioxidants during extraction.


Subject(s)
Flavonoids , Seeds , Vitis , Vitis/chemistry , Seeds/chemistry , Flavonoids/isolation & purification , Flavonoids/chemistry , Flavonoids/analysis , Antioxidants/chemistry , Antioxidants/isolation & purification , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Tocopherols/isolation & purification , Tocopherols/chemistry , Tocopherols/analysis , Tocotrienols/analysis , Tocotrienols/isolation & purification , Tocotrienols/chemistry
2.
Food Chem ; 462: 140956, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39197243

ABSTRACT

The extraction of bioactive compounds is based on the application of various extraction techniques. Therefore, the stem and root bark of the plant species Morinda lucida L. were used in this research, while the extraction procedure was performed using three extraction techniques: HAE (homogenizer extraction), UAE (ultrasound extraction) as modern, and MAC (maceration) as conventional extraction technique. The presence of different classes of secondary metabolites was determined using the UHPLC method, while the content of total phenols and flavonoids was determined spectrophotometrically. The biological potential was investigated by in vitro antioxidant and enzyme assays. Different extraction technologies showed significant differences in only two classes of phenols, namely lignans and phenolic acids, which were significantly higher in HAE than in UAE and MAC. These findings highlight the significant effect of stem and bark extracts of M. lucida, opening the way for innovative industrial exploitation of these matrices.


Subject(s)
Antioxidants , Morinda , Phenols , Plant Extracts , Morinda/chemistry , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Extracts/pharmacology , Phenols/chemistry , Phenols/isolation & purification , Phenols/pharmacology , Antioxidants/chemistry , Antioxidants/isolation & purification , Antioxidants/pharmacology , Chromatography, High Pressure Liquid , Flavonoids/chemistry , Flavonoids/isolation & purification , Plant Bark/chemistry , Chemical Fractionation/methods , Plant Stems/chemistry , Plant Roots/chemistry
3.
Food Chem ; 462: 141007, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39216376

ABSTRACT

In this study, covalent organic frameworks (COFs) were grown in situ on magnetic nitrogen-doped graphene foam (MNGF), and the resulting composite of COFs-modified MNGF (MNC) was wrapped by molecularly imprinted polymers (MNC@MIPs) for specifically capturing SAs. A magnetic solid phase extraction (MSPE) method for SAs was established using MNC@MIPs with good magnetic responsiveness. The adsorption performance of MNC@MIPs was superior to that of non-molecularly imprinted polymers (MNC@NIPs), with shorter adsorption/desorption time and higher imprinting factors. A high-efficiency SAs analytical method was developed by fusing HPLC and MNC@MIPs-based MSPE. This approach provides excellent precision, a low detection limit, and wide linearity. By analyzing fish samples, the feasibility of the approach was confirmed, with SAs recoveries and relative standard deviations in spiked samples in the ranges of 77.2-112.7 % and 2.0-7.2 %, respectively. This study demonstrated the potential use of MNC@MIPs-based MSPE for efficient extraction and quantitation of trace hazards in food.


Subject(s)
Fishes , Food Contamination , Metal-Organic Frameworks , Molecularly Imprinted Polymers , Solid Phase Extraction , Sulfonamides , Solid Phase Extraction/methods , Solid Phase Extraction/instrumentation , Animals , Molecularly Imprinted Polymers/chemistry , Adsorption , Food Contamination/analysis , Metal-Organic Frameworks/chemistry , Sulfonamides/isolation & purification , Sulfonamides/chemistry , Sulfonamides/analysis , Molecular Imprinting , Polymers/chemistry
4.
Food Chem ; 462: 141023, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39217742

ABSTRACT

Type II collagen (Col II) and chondroitin sulfate (CS) are the main macromolecules in the extracellular matrix. This study investigated the characteristics of Col II and CS obtained from chicken sternal cartilage (CSC) via enzymatic hydrolysis for various treatment times. For Col II and CS, the highest efficiency of enzymatic hydrolysis was achieved after 24 and 6 h of treatment, respectively. The average molecular weights were α1 chain-130 kDa, ß chain-270 kDa for Col II, and 80.27 kDa for CS. Fourier transform infrared spectroscopy revealed that the Col II samples maintained their triple-helical structure and that the predominant type of CS was chondroitin-4-sulfate. Scanning electron microscopy revealed that the Col II and CS samples possessed fibrillar and clustered structures, respectively. This study suggests that collagen and CS obtained from CSC can be used as promising molecules for application in food and pharmaceutical industries.


Subject(s)
Cartilage , Chickens , Chondroitin Sulfates , Collagen Type II , Animals , Chondroitin Sulfates/chemistry , Chondroitin Sulfates/isolation & purification , Cartilage/chemistry , Collagen Type II/chemistry , Collagen Type II/metabolism , Molecular Weight , Sternum/chemistry , Hydrolysis , Spectroscopy, Fourier Transform Infrared
5.
Food Chem ; 462: 140936, 2025 Jan 01.
Article in English | MEDLINE | ID: mdl-39232273

ABSTRACT

Aromatic amino acid oxidation products (AAAOPs) are newly discovered risk substances of thermal processes. Due to its significant polarity and trace level in food matrices, there are no efficient pre-treatment methods available to enrich AAAOPs. Herein, we proposed a magnetic cationic covalent organic framework (Fe3O4@EB-iCOF) as an adsorbent for dispersive magnetic solid-phase extraction (DMSPE). Benefiting from the unique charged characteristics of Fe3O4@EB-iCOF, AAAOPs can be enriched through electrostatic interaction and π-π interactions. Under the optimal DMSPE conditions, the combined HPLC-MS/MS method demonstrated good linearity (R2 ≥ 0.990) and a low detection limit (0.11-7.5 µg·kg-1) for AAAOPs. In addition, the method was applied to real sample and obtained satisfactory recoveries (86.8 % âˆ¼ 109.9 %). Especially, we applied this method to the detection of AAAOPs in meat samples and conducted a preliminarily study on its formation rules, which provides a reliable basis for assessing potential dietary risks.


Subject(s)
Amino Acids, Aromatic , Oxidation-Reduction , Solid Phase Extraction , Solid Phase Extraction/methods , Amino Acids, Aromatic/chemistry , Amino Acids, Aromatic/analysis , Amino Acids, Aromatic/isolation & purification , Tandem Mass Spectrometry , Metal-Organic Frameworks/chemistry , Hot Temperature , Food Contamination/analysis , Chromatography, High Pressure Liquid , Animals , Adsorption , Meat/analysis , Food, Processed
6.
J Hazard Mater ; 479: 135653, 2024 Aug 27.
Article in English | MEDLINE | ID: mdl-39217939

ABSTRACT

In this study, a novel COFTABT@COFTATp modified magnetic MXene composite (CoFe2O4 @Ti3C2 @COFTABT@COFTATp) was synthesized by Schiff base reaction and irre-versible enol-keto tautomerization, and employed to establish a sensitive monitoring method for six thiophene compounds in oilfield produced water samples based on magnetic solid-phase extraction (MSPE) prior to gas chromatography coupled with a triple quadruple mass spectrometer (GC-MS/MS). The designed magnetic materials exhibited unexpected enrichment ability to target thiophene compounds and achieved good extraction efficiencies ranging from 83 % to 98 %. The developed MSPE/GC-MS/MS method exhibited good linearity in the range of 0.001-100 µg L-1, and obtained lower limits of detection ranging from 0.39 to 1.9 ng L-1. The spiked recoveries of thiophene compounds obtained in three oilfield produced water samples were over the range of 96.26 %-99.54 % with relative standard deviations (RSDs) less than 3.7 %. Notably, benzothiophene, 4-methyldibenzothiophene and 4,6-dimethyldibenzothiophene were detected in three oilfield-produced water samples. Furthermore, the material still kept favorable stability after six recycling experiments. The adsorption kinetics, adsorption isotherms as well as adsorption thermodynamics of thiophene compounds were investigated in detail to provide insight into the mechanisms. Overall, the present work contributed a promising strategy for designing and synthesizing new functionalized materials for the enrichment and detection of typical pollutants in the environment.

7.
J Agric Food Chem ; 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39230505

ABSTRACT

Aflatoxins pose a major health concern and require strict monitoring in food products. Existing methods rely on hazardous organic solvents for extraction, prompting the development of a greener alternative. This study explores deep eutectic solvents (DESs) for aflatoxin extraction from pistachios, a valuable food product prone to aflatoxin contamination. The proposed method utilizes DES extraction followed by solid-phase extraction cleanup and ultrahigh-performance liquid chromatography coupled with fluorescence detector analysis. Recovery rates ranged from 85.5 to 99.1% for pistachios spiked with 1-8 ng/g aflatoxins, in compliance with EU regulations, with coefficients of variation less than 2.94%. The method demonstrates good sensitivity with limits of detection and quantification in the range of 0.02-0.22 ng/g and 0.05-0.72 ng/g, respectively. Greenness assessment using AGREEPrep and White Analytical Chemistry metrics confirms its environmental sustainability. This approach offers a promising, safer, and more eco-friendly alternative for aflatoxin extraction from complex food matrices like pistachios.

8.
J Imaging Inform Med ; 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39230872

ABSTRACT

The precise delineation of the pancreas from clinical images poses a substantial obstacle in the realm of medical image analysis and surgical procedures. Challenges arise from the complexities of clinical image analysis and complications in clinical practice related to the pancreas. To tackle these challenges, a novel approach called the Spatial Horned Lizard Attention Approach (SHLAM) has been developed. As a result, a preprocessing function has been developed to examine and eliminate noise barriers from the trained MRI data. Furthermore, an assessment of the current attributes is conducted, followed by the identification of essential elements for forecasting the impacted region. Once the affected region has been identified, the images undergo segmentation. Furthermore, it is crucial to emphasize that the present study assigns 80% of the data for training and 20% for testing purposes. The optimal parameters were assessed based on precision, accuracy, recall, F-measure, error rate, Dice, and Jaccard. The performance improvement has been demonstrated by validating the method on various existing models. The SHLAM method proposed demonstrated an accuracy rate of 99.6%, surpassing that of all alternative methods.

9.
Article in English | MEDLINE | ID: mdl-39225779

ABSTRACT

OBJECTIVE: Clinical notes contain unstructured representations of patient histories, including the relationships between medical problems and prescription drugs. To investigate the relationship between cancer drugs and their associated symptom burden, we extract structured, semantic representations of medical problem and drug information from the clinical narratives of oncology notes. MATERIALS AND METHODS: We present Clinical concept Annotations for Cancer Events and Relations (CACER), a novel corpus with fine-grained annotations for over 48 000 medical problems and drug events and 10 000 drug-problem and problem-problem relations. Leveraging CACER, we develop and evaluate transformer-based information extraction models such as Bidirectional Encoder Representations from Transformers (BERT), Fine-tuned Language Net Text-To-Text Transfer Transformer (Flan-T5), Large Language Model Meta AI (Llama3), and Generative Pre-trained Transformers-4 (GPT-4) using fine-tuning and in-context learning (ICL). RESULTS: In event extraction, the fine-tuned BERT and Llama3 models achieved the highest performance at 88.2-88.0 F1, which is comparable to the inter-annotator agreement (IAA) of 88.4 F1. In relation extraction, the fine-tuned BERT, Flan-T5, and Llama3 achieved the highest performance at 61.8-65.3 F1. GPT-4 with ICL achieved the worst performance across both tasks. DISCUSSION: The fine-tuned models significantly outperformed GPT-4 in ICL, highlighting the importance of annotated training data and model optimization. Furthermore, the BERT models performed similarly to Llama3. For our task, large language models offer no performance advantage over the smaller BERT models. CONCLUSIONS: We introduce CACER, a novel corpus with fine-grained annotations for medical problems, drugs, and their relationships in clinical narratives of oncology notes. State-of-the-art transformer models achieved performance comparable to IAA for several extraction tasks.

10.
J Chromatogr A ; 1736: 465351, 2024 Sep 07.
Article in English | MEDLINE | ID: mdl-39260149

ABSTRACT

On-site extraction plays a significant role in the reliable quantification of strong polar phenoxycarboxylic acid herbicides (PCAs) in aqueous samples. In current study, a new technique for the field sample preparation of PCAs was developed by means of three channels in-tip microextraction device (TCIM). To capture PCAs effectively, an extraction phase based on monolith (EPM) using vinylimidazole and divinylbenzene/ethylene dimethacrylate as monomer and cross-linkers, respectively, was in-situ synthesized in pipette tips. The EPM fabricated at optimal conditions were characterized by a series of techniques and employed as the adsorbent of TCIM for the on-site extraction of PCAs. The adsorption isotherm was studied so as to inspect the extraction behaviors of EPM towards PCAs. Results revealed that the proposed EPM/TCIM presented satisfactory extraction performance towards PCAs through multiple interactions. The enrichment factors and adsorption capacity were 74-277 and 20 mg g-1, respectively. Under the most beneficial extraction parameters, the developed EPM/TCIM was successfully employed to on-site extract PCAs, and then combining with HPLC equipped with diode array detector to monitor trace PCAs in actual waters. The limits of detection (LODs) towards investigated PCAs varied from 0.071 µg/L to 0.30 µg/L. In addition, the accuracy of established approach was inspected with documented method. Compared with existing lab-based sample preparation approaches, the introduced field sample preparation technique exhibits some merits such as avoidance of transporting large volume of water, prevention of analytes loss during sampling procedure, less usage of organic solvent and achievement of satisfactory efficient in sample preparation.

11.
Food Chem ; 463(Pt 1): 141167, 2024 Sep 06.
Article in English | MEDLINE | ID: mdl-39260172

ABSTRACT

Grain Rain Period (GRP), one of the 24 solar terms in China, signifies a crucial phase for the transformation of tea quality, especially for Lu'an Guapian (LAGP) tea. During GRP, LAGP teas showed 3 distinct aroma profiles, each spanning 3-4 days. Specifically, the sensory evaluation result revealed that LAGP tea exhibited stronger flowery and fresh aromas in the early phase, with the soybean-like aroma significantly intensifying as the harvest period progressed during GRP. Furthermore, the key contributors to the aroma profile and its variation during GRP were identified as indole, δ-decalactone, geraniol, linalool, decanal, jasmone, (E)-ß-ionone, benzeneacetaldehyde, dihydroactinolide, nonanal, octanal, (E)-isoeugenol, (E,E)-2,4-nonadienal, 4-ketoisophorone, (E,Z)-2,6-nonadienal, and 1-octen-3-one. Additionally, we proposed a binary blending strategy using sensory evaluation with the methods of triangle test and normal distribution fitting to predict the blending threshold accurately. This study elucidated the dynamics of LAGP tea aroma during GRP and offered insights for tea blending optimization.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 325: 125104, 2024 Sep 07.
Article in English | MEDLINE | ID: mdl-39260240

ABSTRACT

A novel method for the rapid identification of hemp fibers is proposed in this paper, utilizing terahertz time-domain spectroscopy (THz-TDS) combined with the LargeVis (LV) dimensionality reduction technique. This approach takes advantage of the strengths of THz-TDS while enhancing classification accuracy through LV. To verify the efficacy of this method, terahertz absorption spectral data from three types of hemp fibers were processed. The THz absorption spectra were initially preprocessed using Hanning filtering. Following this, the filtered data underwent dimensionality reduction through three distinct methods: linear Principal Component Analysis (PCA), nonlinear t-Distributed Stochastic Neighbor Embedding (t-SNE), and the LV method. This sequence of steps resulted in a two-dimensional feature data matrix derived from the THz source spectral data. The resultant feature data matrices were then input into both K-Nearest Neighbors (KNN) and Decision Tree (DT) classifiers for analysis. The classification accuracies of six models were evaluated, revealing that the LV-KNN model achieved a 86.67% accuracy rate for the three hemp fiber types. Impressively, the LV-DT model achieved a perfect 100.00% accuracy rate for the same fibers. The LV-DT model, when integrated with THz spectroscopy technology, offers a quick and precise method for identifying various types of hemp fibers. This development introduces an innovative optical measurement scheme for the characterization of textile materials.

13.
Anal Chim Acta ; 1326: 343138, 2024 Oct 16.
Article in English | MEDLINE | ID: mdl-39260916

ABSTRACT

BACKGROUND: Sulfonamide (SA) residues in food of animal origin possess a potential threat to human health and environment. However, due to the polar and ionic characteristics and trace level of SAs and the complexity of food matrices, direct measurement of SAs in these samples is still very difficult. Development of efficient sample pretreatment method for sensitive and selective extraction of trace SAs is of great significance and urgently desired. Therefore, rational design and synthesizing advanced and selective extractants is quite important. RESULTS: In this work, a novel phenazine-based microporous organic network (MON) named TEPM-DP is reasonably synthesized and employed as a packing material for selective solid phase extraction (SPE) and sensitive determination of four typical SAs in milk samples. Phenazine-based monomer with aromatic and heteroaromatic ring and numerous N atoms is chosen to construct TEPM-DP adsorbent to provide π-π, hydrogen bonding, hydrophobic, and electrostatic extraction sites for SAs. The proposed method owns wide linear ranges, low limits of detection, high enrichment factors, and good precisions and recoveries for SAs in complex milk samples. The recoveries of SAs on TEPM-DP are much higher than those of commercial C18 and activated carbon. The extraction mechanisms are also elucidated via FT-IR, XPS, and comparative experiments. SIGNIFICANCE: This work reports the first example of design and synthesizing phenazine-based MON in SPE via a simple and rapid solvothermal method. The results reveal the great prospects of TEPM-DP for enriching polar and ionic SAs in complex samples and uncover the potency of phenazine-based MON in sample pretreatment, which will promote the development of MON.


Subject(s)
Milk , Phenazines , Solid Phase Extraction , Sulfonamides , Phenazines/chemistry , Milk/chemistry , Animals , Sulfonamides/analysis , Sulfonamides/isolation & purification , Solid Phase Extraction/methods , Porosity , Limit of Detection , Adsorption , Food Contamination/analysis
14.
BMC Oral Health ; 24(1): 1072, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39261783

ABSTRACT

BACKGROUND: There is a general consensus among dental professionals regarding the extraction of impacted third molars in the presence of clinical symptoms. However, there is less agreement on the management of asymptomatic third molars. The objective of this study is to compare the perspectives of oral surgeons and orthodontists regarding the indications for the extraction of asymptomatic third molars. It is possible that healthcare professionals from different specialties may approach the extraction of these teeth in different ways. METHODS: In this cross-sectional study, a web-based questionnaire has been employed to collect data by inquiring about the reasons why participants prefer the extraction of asymptomatic third molars. Descriptive statistics were employed to evaluate the data obtained. The level of significance was set at P < 0.05. RESULTS: Prophylactic extraction of partially impacted molars was more favored among the participants (P < 0.05). The orthodontists preferred prophylactic extraction due to the risk of late anterior dental crowding (LADC); however, the oral surgeons preferred pre-pregnancy extractions (P < 0.05). The extraction decision for partial impaction was higher in females when the risk of distal caries was considered. For fully impacted ones, it was higher in males when the risk of caries and pericoronitis were considered (P < 0.05). CONCLUSIONS: Orthodontists preferred extraction because of the risk of LADC and caries, while oral surgeons focused on preventing pericoronitis, pathology, focal infection, and symptoms during pregnancy. This divergence between the participants may inform the guidelines for prophylactic management of third molars. These findings may be pertinent in gender medicine. CLINICAL RELEVANCE: This study has been enlightening for departments to consult each other before the extraction of a patient's asymptomatic third molar.


Subject(s)
Molar, Third , Orthodontists , Tooth Extraction , Tooth, Impacted , Humans , Molar, Third/surgery , Cross-Sectional Studies , Male , Female , Tooth, Impacted/surgery , Practice Patterns, Dentists'/statistics & numerical data , Adult , Surveys and Questionnaires , Oral and Maxillofacial Surgeons , Attitude of Health Personnel , Dental Caries/prevention & control , Malocclusion/prevention & control
15.
BMC Surg ; 24(1): 255, 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39261821

ABSTRACT

With the continuous advancements in precision medicine and the relentless pursuit of minimally invasive techniques, Natural Orifice Specimen Extraction Surgery (NOSES) has emerged. Compared to traditional surgical methods, NOSES better embodies the principles of minimally invasive surgery, making scar-free operations possible. In recent years, with the progress of science and technology, Robot-Assisted Laparoscopic Surgery has been widely applied in the treatment of colorectal cancer. Robotic surgical systems, with their clear surgical view and high operational precision, have shown significant advantages in the treatment process. To further improve the therapeutic outcomes for colorectal cancer patients, some scholars have attempted to combine robotic technology with NOSES. However, like traditional open surgery or laparoscopic surgery, the use of the robotic platform presents both advantages and limitations. Therefore, this study reviews the current research status, progress, and controversies regarding Robot-Assisted Laparoscopic Natural Orifice Specimen Extraction Surgery for colorectal cancer, aiming to provide clinicians with more options in the diagnosis and treatment of colorectal cancer.


Subject(s)
Colorectal Neoplasms , Laparoscopy , Natural Orifice Endoscopic Surgery , Robotic Surgical Procedures , Humans , Colorectal Neoplasms/surgery , Robotic Surgical Procedures/methods , Natural Orifice Endoscopic Surgery/methods , Laparoscopy/methods , Forecasting , Specimen Handling/methods
16.
Heliyon ; 10(17): e36270, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39263112

ABSTRACT

This study investigated the viability of locally available organic sources of Azadirachta indica leaf as vegetable tannin agent in leather processing to promote green leather manufacturing. Leather tanned with Azadirachta indica leaf powder (NPT), extract (NET) and conventional vegetable tanned leather (CVT) was characterized with FTIR, DLS, HPLC, DSC, TGA, and SEM. Total soluble solid, pH, tannin content, and tanning strength of Azadirachta indica leaf extract were found to be 24 %, 4.81, 12.34 % and 1.81 respectively. Moisture content, fat content, and water-soluble content of Azadirachta indica leaf extract tanned leather (NET) were 12.26 %, 10.8 % and 7.2 % respectively. The shrinkage temperature, tensile strength, stitch tear strength, grain crack load, and finished film bond strength of NET leather were 86 °C, 282.52 kg/cm2, 139.53 kg/cm, 24 kg, and 414 g/cm respectively. NET leather exhibited better anti-microbial sensitivity against E. coli, S. aureus, and P. aeruginosa than NPT and NET leather. Overall, the experimental results of this study indicate the A. indica leaf could serve as a prime renewable tanning agent, substituting hazardous chromium and imported conventional vegetable tannin chemicals in leather manufacturing. Thus, developed A. indica leaf tannin material from plant sources could provide sustainable leather production, contributing to eco-friendly and viable green leather processing options.

17.
Environ Sci Technol ; 2024 Sep 12.
Article in English | MEDLINE | ID: mdl-39263826

ABSTRACT

Lithium is a critical mineral in a wide range of current technologies, and demand continues to grow with the transition to a green economy. Current lithium mining and extraction practices are often highly ecologically damaging, in part due to the large amount of water and energy they consume. Biomineralization is a natural process that transforms inorganic precursors to minerals. Microbial biomineralization has potential as an ecofriendly alternative to current lithium extraction techniques. This work demonstrates Lysinibacillus sphaericus biomineralization of lithium chloride to lithium hydroxide. Quantitative analysis of biomineralized lithium via the 2-(2-hydroxyphenyl)-benzoxazole fluorescence assay reveals significantly greater recovery with L. sphaericus than without. Furthermore, L. sphaericus biomineralization is specific to lithium over sodium. The nanoparticles produced were further characterized via Fourier transform infrared and transmission electron microscopy analysis as crystalline lithium hydroxide, which is an advanced functional material. Finally, ESI-LC/MS was used to identify several proteins involved in this microbial biomineralization process, including the S-layer protein. Through the isolation of L. sphaericus ghosts, this work shows that the S-layer protein alone plays a critical role in the biomineralization of crystalline lithium hydroxide nanoparticles. Through this study of microbial biomineralization of lithium with L. sphaericus, there is potential to develop innovative and environmentally friendly extraction techniques.

18.
Article in English | MEDLINE | ID: mdl-39264496

ABSTRACT

Perfluoroalkyl substances (PFAS) are chemical compounds that have been widely used in industry and manufacture. Occurrence, together with persistence and recent toxicological effects data, has promoted the regulation of 20 PFAS (carboxylic and sulfonic) acids in drinking water through the recent Directive 2020/2184/EU. This Regulation included PFAS with different carbon chain lengths (from C4 to C13) and limited the total PFAS concentration (as sum) to a maximum of 0.1 µg/L, for which law-enforcement analytical methods are required. In this work, three different methodologies have been developed and evaluated as regards their performance to determine those 20 PFAS in tap and bottled water, based on on-line and off-line solid-phase extraction (SPE) and direct injection. In all cases, ultra-high pressure liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) was used as a determination technique. Off-line SPE with Oasis Weak Anion Exchange (WAX) cartridges provided the best results in terms of limits of quantification (LOQ ≤ 0.3 ng/L) and accuracy (R ≥ 70%) in drinking water samples. On-line SPE and direct injection presented some drawbacks such as background contamination problems and lower accuracies for the least polar compounds. This off-line SPE methodology was then applied to the analysis of 46 drinking water samples (11 commercial bottled samples, 23 Spanish and 12 international tap water samples). Ten PFAS were quantified in such samples at concentrations and detection frequencies ranging from 0.1 to 20.1 ng/L and 2 to 91%, respectively. However, the sum concentration did not surpass the established limit in any sample.

19.
Sci Total Environ ; 953: 176009, 2024 Sep 02.
Article in English | MEDLINE | ID: mdl-39233074

ABSTRACT

Quantifying trace levels of microplastics in complex environmental media remains a challenge. In this study, an approach combining field collection of samples from different depths, sample size fractionation, and plastic quantification via pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) was employed to identify and quantify microplastics at two public beaches along the northeast coast of the U.S. (Salisbury beach, MA and Hampton beach, NH). A simple sampling tool was used to collect beach sand from depth intervals of 0-5 cm and 5-10 cm, respectively. The samples were sieved to give three size fractions: coarse (>1.2 mm), intermediate (100 µm-1.2 mm), and fine (1.2 µm-100 µm) particles. Following density separation and wet peroxide oxidation, a low-temperature solvent extraction protocol involving 2-chlorophenol was used to extract polyester (PET), polystyrene (PS), polyamide (PA), and polyvinyl chloride (PVC). The extract was analyzed using Py-GC-MS for the respective polymers, while the solid residue was pyrolyzed separately for polyethylene (PE) and polypropylene (PP). The one-step solvent extraction method significantly simplified the sample matrix and improved the sensitivity of analysis. Among the samples, PET was detected in greater quantities in the fine fraction than in the intermediate size fraction, and PET fine particles were located predominantly in the surface sand. Similar to PET, PS was detected at higher mass concentrations in the fine particles in most samples. These results underscore the importance of beach environment for plastic fragmentation, where a combination of factors including UV irradiation, mechanical abrasion, and water exposure promote plastic breakdown. Surface accumulation of fine plastic particles may also be attributed to transport of microplastics through wind and tides. The proposed sample treatment and analysis methods may allow sensitive and quantitative measurements of size or depth-related distribution patterns of microplastics in complex environmental media.

20.
J Pharmacol Toxicol Methods ; 129: 107549, 2024 Sep 03.
Article in English | MEDLINE | ID: mdl-39236994

ABSTRACT

Ribonucleic acid (RNA) extraction and purification play pivotal roles in molecular biology and cell and gene therapy, where the quality and integrity of RNA are critical for downstream applications. Automated high-throughput systems have gained interest due to their potential for scalability and reduced labor requirements compared to manual methods. However, ensuring high-throughput capabilities, reproducibility, and reliability while maintaining RNA yield and purity remains challenging. This study evaluated and compared the performance of four commercially available high-throughput magnetic bead-based RNA extraction kits across six types of naïve non-human primate (NHP) tissue matrices: brain, heart, kidney, liver, lung, and spleen. The assessment focused on RNA purity, yield, and extraction efficiency (EE) using Xeno Internal Positive Control (IPC) spiking. Samples (∼50 mg) were homogenized via bead-beating and processed according to the manufacturer's protocol on the KingFisher Flex platform in eight replicates. RNA purity and yield were measured using a NanoDrop® spectrophotometer, while EE was evaluated via real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The findings indicate consistent high RNA purity across all tested extraction kits, yet substantial variation in RNA yield. Extraction efficiency exhibited variations across tissue types, with decreasing trends observed from brain to lung tissues. These results underscore the importance of careful kit selection and method optimization for achieving reliable downstream applications. The MagMAX™ mirVana™ Total RNA Isolation Kit stands out as the most accurate and reproducible, making it the preferred choice for applications requiring high RNA quality and consistency. Other kits, such as the Maxwell® HT simplyRNA Kit, offer a good balance between cost and performance, though with some trade-offs in precision. These findings highlight the importance of selecting the appropriate RNA isolation method based on the specific needs of the research, underscoring the critical role of accurate nucleic acid extraction in gene and cell therapy research. In conclusion, this study highlights the critical factors influencing RNA extraction performance, emphasizing the need for researchers and practitioners to consider both kit performance and tissue characteristics when designing experimental protocols. These insights contribute to the ongoing efforts to enhance the reproducibility and reliability of RNA extraction methods in molecular biology and cell/gene therapy applications.

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