Solid Samples Research Articles

Multivariate analysis of DTMS data for elucidating the chemistry behind soft and dripping paint

The problem of soft and dripping oil paint in mid-20th-century paintings was investigated using high-resolution direct temperature-resolved mass spectrometry (DTMS) and multivariate data analysis techniques. Nineteen paintings by Asger Jorn, Karel Appel, Pierre Alechinsky and Jean-Paul Riopelle were examined, and selected areas were tested for material properties and water sensitivity. Samples were taken from these areas and subjected to DTMS, and the data collected were analysed with principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA). PCA loadings showed grouping of variables belonging to similar chemical structures, but the scores showed only clear clustering of samples classified as solid and healthy. The other categories showed large variability in chemical composition. No clustering on water sensitivity was found. With PLS-DA, chemical markers were detected for the solid and healthy samples that are correlated to the presence of fish oil. Further investigation showed strong indications for the presence of chemical components related to fish oil in many samples from the other categories as well. Earlier hypotheses on the issue of soft and dripping oil paint, based on observations on a single or small group of paintings, could not be confirmed. In this study, it was also shown that using low resolution DTMS may lead to incorrect conclusions, because different chemical components with the same nominal mass can be anti-correlated.

Dispersion behaviour of acousto-ultrasonic signals in HTPB based solid propellants

ABSTRACT Acousto-Ultrasonic Testing (AUT) was performed on Hydroxyl-Terminated Polybutadiene (HTPB)-based solid rocket propellant samples to study the dispersion behaviour of mechanical waves within the material. Low-frequency mechanical waves, ranging from 10 kHz to 300 kHz, were used for testing. The results demonstrated that the stress wave velocity increased non-linearly with increasing frequency and sample thickness. Additionally, propellant samples subjected to natural ageing were analysed for mechanical properties, such as modulus, and these properties were correlated with stress wave velocity. This study aims to monitor variations in mechanical properties over time, revealing correlation between changes in mechanical properties and computed stress wave velocity. An average increase in wave velocity of approximately 25% is observed over a duration of 14 months. A corresponding enhancement in the elastic modulus, estimated at ~ 1.25 MPa (approximately 30%), is evident during the early stages of natural ageing. Experimental investigations on the variations in velocity with stress wave frequency and sample thickness are detailed.

Strata-based approach for determination of resource recovery potential from legacy waste dumpsite in India.

The growing interest in recovering resources from old dumpsites has greatly accelerated the adoption of landfill mining (LFM) in recent years. This study focuses on assessing the quality of materials recovered from diverse legacy waste dumpsites using a strata-based approach. The method involved waste characterization, elemental analysis, physico-chemical characterization, heavy metals analysis and correlation analysis to assess the potential of solid waste samples collected from all three layers. Results revealed intriguing patterns in waste composition, with an increase in soil like fractions with depth and percentage of single-use plastic was almost same in all layers. Elemental analysis revealed variations in nitrogen, carbon, hydrogen and sulphur content across different layers, showcasing the heterogeneity of legacy. There was a small variation in the percentage of carbon in the first two layers, indicating high potential for use as fuel in the form of refuse-derived fuels. Significant changes were observed in layer 3, indicating it is best suited for landfill gas collection. Similar trends were observed for other elements. The presence of nitrogen-rich content indicates the potential for ammonia production, whereas hydrogen-rich materials suggest the possibility of generating hydrogen gas. Sulphur-rich waste holds promise for contributing to sulphur dioxide production. Correlation analysis was performed to maximize resource recovery while minimizing environmental risks.

Analytical Techniques for the Determination of Elemental Composition of Coffee

According to the Coffee Market Report (2024) of the International Coffee Organization, the annual worldwide production of coffee increased 5.82% achieving 178 million bags between 2023 and 2024. South America is the coffee production leader accounting for 50.17% of the global production with Brazil playing a central role on it. To sustain the high quality standards under such a high demand, it is important to ensure the consumer health safety, while preserving the good flavor and aroma of coffee (terroir). Some key factors are required to allow the proper evaluation of crops and shipments using reliable parameters, which is the case of the determination of the elemental composition of coffee. Coffee organoleptic properties depend on several chemical elements of its composition, while accessing and monitoring their concentrations is challenging, since they might vary considerably according to some agronomical and climatic conditions that plantations are subjected. Yet, the analytes might not be homogeneously distributed throughout samples, demanding both refined solid sampling strategies and laborious sample preparation and pretreatment. Finally, several analytical techniques are available for researches and analysts to investigate the elemental composition of coffee samples, each one with their own advantages, limitations and particularities. Sometimes it is not a trivial task to choose a proper technique according to the aimed data. Therefore, an overview of the analysis of coffee elemental composition is herein presented, covering selected references from the last two decades. The selected works discuss the determination of elements affecting the quality of coffee in terms of terroir, toxicity, nutritional content, and geographical origin.

Paper as a Sustainable Material for Smart Electrochemical (Bio)sensors with Unprecedented Features: A Perspective.

This perspective has the overriding goal of reporting the tipping points in the roadmap of electrochemical paper-based analytical devices by harnessing the multiple paper characteristics such as cost-effectiveness, widespread accessibility, mechanical strength, porosity, and capability to be easily cut, folded, modified, and assembled. The use of paper in electrochemical devices not only provides additional features to the electrochemical devices such as the environmentally friendless, ease multiplexed analysis, and three tridimensional structures by folding and unfolding operations but has broken down barriers for delivering measurement without (i) addition of reagents, (ii) sample treatment for liquid, aerosol, and solid samples, and (iii) any additional pump for microfluidics. I lay out the advantages of using paper for the design of multifarious electrochemical devices, underlying the next steps in the paper-based electrochemical device roadmap.

Rapid on-site determination of heavy metals and metalloids in contaminated biochar samples by accelerated leaching process coupled with voltammetric sensors.

Rapid on-site determination of heavy metals and metalloids in contaminated biochar samples by accelerated leaching process coupled with voltammetric sensors.

Smartphone-aided fluorescent probe combining lateral flow assay for Cys testing in food and organism.

Smartphone-aided fluorescent probe combining lateral flow assay for Cys testing in food and organism.

Ruminal microbial responses to Moringa oleifera feed in lactating goats (Capra hircus): A metagenomic exploration.

Ruminal microbial responses to Moringa oleifera feed in lactating goats (Capra hircus): A metagenomic exploration.

Application of Pyrohydrolysis-Ion Chromatography and INAA Techniques for chloride determination in soil and rock phosphate matrices

ABSTRACT Determining chlorine levels in high silica based matrices like soil and minerals is crucial for agriculture, environmental management, and human health. This study presents a comprehensive methodology utilizing pyrohydrolysis-Ion Chromatography with a U3O8 accelerator for chloride separation from soil samples. The results were compared with well known solid sample analysis technique, Instrumental Neutron Activation Analysis. The total chlorine concentrations in rock phosphates and bentonites as well as reference materials are in the range of 70 to 200 mg kg−1. The limit of detection for chlorine/chloride using developed the pyrohydrolysis-Ion Chromatography methodology was 12 mg kg−1.

Abstract 218: Long-read nanopore sequencing in pursuit of complete methylation profiling of Hungarian colorectal cancer patients

Abstract Introduction: Variations of the epigenetic landscape are the hallmark of many pathologies, including cancer. We investigated the Hungarian colorectal cancer cohort via Oxford Nanopore’s long-read whole-genome sequencing (WGS) platform to provide for the first time a genome-spanning methylation report of the country. A prominent benefit of the method is native, and so, bias-free detection of modified or alternative nucleotides. Aims & Methods: We selected 136 tissue biopsy, resection, normal adjacent tissue (NAT) and peripheral buffy coat (BC) samples from patients of Semmelweis University, to represent the range of pathological progression: healthy - adenoma (AD) - carcinoma (CRC). After thorough quality control by fragment length analysis (Tape Station), WGS was carried out on Nanopore’s PromethION platform in simplex basecalling mode. Bioinformatic analysis utilized the Nanopore software package, Dorado basecaller and our custom scripts. We focused on methylation and hydroxymethylation of cytosine residues as the most abundant form of epigenetic marks. Results: Coverage is 19.3x (±0.13), with an average read length and precision of 4.3 (±0.16) kb and 98% (±0.01), respectively; median PHRED is 16.03 (±1.18) and N50 is 7807 (±2262). Average GC ratio is 47% (±7%), island-mapped CpG sites show 69% (±5%) average methylation, of which 5hmC accounts for 5.68% (±1.88%), showing significant variations between groups: from 71% (healthy individuals), average methylation drops by 4.1% (AD, p=0.013), 8.8% (CRC, p=0.007), and 12.9% (resection, p<0.001) in solid tumors; by 0.1% (AD) and 2.5% (CRC) in buffy coats (not significant); and by 2.7% (CRC, p=0.01), and 4.6% (resection, p<0.001) in NAT samples. Solid samples always show significant hypomethylation compared to buffy coats. Contrasting this, 5hmC reveals a different pattern: it is relatively stable in solid samples and buffy coats, but rises by 47% (CRC, p<0.001) and 56% (resection, p<0.001) in normal adjacent tissues. When matching the tumor and healthy tissue of the same patient, we also see significant hypomethylation: 5mC decreases by 7% (±2.1%, p=0.005), and 5hmC by 31.4% (±3.9%, p<0.001) with very few exceptions. Conclusion: long-read WGS is a strong tool for studying methylation in solid and liquid samples of colorectal cancer patients, revealing marked differences between solid and liquid samples, and also between tumor and healthy tissue. We corroborated the general cytosine hypomethylation associated with cancer, while also observing new trends in hydroxymethylation. Citation Format: Kristóf R. Rada, Nikolett Szakállas, Barbara Barták, Alexandra Kalmár, István Takács. Long-read nanopore sequencing in pursuit of complete methylation profiling of Hungarian colorectal cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 218.

Abstract 691: Decentralized pan-cancer tumor profiling: a comprehensive performance evaluation of the MSK-IMPACT® Assay with SOPHiA DDMTM

Abstract Background: Molecular profiling of solid tumors through FFPE (Formalin-Fixed Paraffin-Embedded) tissue samples is crucial for personalized cancer treatment. MSK-IMPACT® (Memorial Sloan Kettering - Integrated Mutation Profiling of Actionable Cancer Targets) is a well-established, high-throughput genomic assay designed to identify known cancer-driving alterations in solid tumors from FFPE tissue samples. SOPHiA GENETICS is developing a decentralized version of this assay, integrating key features of MSK-IMPACT® including comprehensive genomic profiling, the utilization of hybrid capture-based next-generation sequencing, and the identification of actionable somatic mutations. This report presents the results from a performance evaluation study conducted during the development of this product. Methods: A cohort of 167 FFPE solid tumor samples and matched normal tissue were collected from cancer patients and processed at MSKCC (Memorial Sloan Kettering Cancer Center) according to the validated standard operating procedures for MSK-IMPACT®, which involves DNA extraction, library preparation, hybrid capture targeting 505 actionable cancer genes, and sequencing on an Illumina platform. In parallel, SOPHiA GENETICS processed the same samples using proprietary enrichment techniques, and sequencing was performed on Illumina platforms. Somatic variants were identified using a robust bioinformatics pipeline, and the results were compared with those obtained by MSKCC to assess the accuracy of the decentralized “MSK-IMPACT® powered with SOPHiA DDM™” solution. Results: A total of 1736 somatic mutations were detected, with variant allele fractions (VAF) as low as 1.1% and a median of 5 variants with coding impact per sample. The positive percent agreement (PPA) for all detected variants with the original MSK-IMPACT® assay is 99.3% for SNV/INDEL with a PPA >98% down to 2.5-6% VAF. Furthermore, PPA for CNVs is 94.6%, and overall percent agreement for MSI and TMB of 99.4% and 98.8%, respectively. Conclusions: The findings affirm that the decentralized “MSK-IMPACT® powered with SOPHiA DDM™” solution delivers a high level of concordance with the established results by MSK-IMPACT®. Future studies are planned to further verify the analytical and clinical performance and to evaluate the utility in routine clinical practice. This solution equips laboratories with a premier, comprehensive testing capability that identifies SNV/INDEL, CNV, DNA fusion, and the critical immuno-oncology biomarkers TMB and MSI. Citation Format: Julien Pontis, Fuad Mohammad, Anjali Anjali, Yvan Wenger, Florian Klemm, Anita F. Bowman, Brian Houck-Loomis, Jacklyn Casanova-Murphy, A. Rose Brannon, Micheal F. Berger, Zhenyu Xu. Decentralized pan-cancer tumor profiling: a comprehensive performance evaluation of the MSK-IMPACT Assay with SOPHiA DDM [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 691.

Abstract 6523: A multi-omics analysis correlating intratumoral microbial abundance with methylation patterns in hepatocellular carcinoma

Abstract Background: Liver Hepatocellular Carcinoma (LIHC) is estimated to be the fourth leading cause of cancer worldwide. LIHC is often aggressive, as most patients are diagnosed at advanced stages. Our study aims to understand the molecular mechanisms driving the development and progression of LIHC. The microbiome has been hypothesized to contribute to many diseases, including cancer. Although microbes reside primarily within the gut, they may translocate to the liver by the gut-liver axis. Such microbes may produce metabolites that can regulate epigenetics. DNA methylation influences tumor progression by silencing tumor suppressors and activating oncogenes. Using the theoretical framework of metabolite interactions, we explore the correlation between microbe abundance and methylation patterns to expand research on the pathogenesis of LIHC. Methods: We analyzed sequencing data for 376 primary LIHC tumor samples and 85 solid tissue normal samples from The Cancer Genome Atlas (TCGA). Using the PathoScope 2.0 framework, we successfully extracted microbial read counts from 446 samples. Microbial contamination correction was performed by three methods: sequencing date, sequencing plate, and overall microbial abundance. Bacterial species identified as contaminants were excluded from downstream analysis. Differential abundance analysis was conducted to identify bacteria species with altered abundance between normal and tumor samples. We used the Kruskal-Wallis test with a Bonferroni-adjusted p-value threshold of 0.05. Methylation data was downloaded from TCGA and filtered by a panel of genes relevant to LIHC oncogenesis. Methylation score disparities between cancer and normal tissues were assessed by the Kruskal-Wallis test. We employed Spearman's rank correlation to identify associations between microbial counts and methylation scores. Results: We identified 27 differentially expressed microbes and 533 differentially methylated sites in LIHC tissue (p-value < 0.05). Between these microbes and methylation sites, we found 58 statistically significant correlations between the microbial abundance and methylation scores (p-value < 0.05). Notably, species involved in these correlations include the pathogenic E. coli O26:H11 str. 11368 and E. coli UMN026 and the probiotic Ligilactobacillus salivarius. Additional findings indicate significant microbial and methylation correlations, with further analysis underway to integrate these findings with clinical variables including cancer stage and alcohol consumption history. Additionally, microbial metabolic pathways are profiled using the HUMAnN 3.0 pipeline to provide insights into the potential mechanisms by which the microbiome may influence methylation. Further research is needed to elucidate the specific pathways mediating epigenetic modifications induced by the bacterial microbiome. Citation Format: Tianyi Chen, Annie N. Do, Suravi Bajaj, Erin Jang, Rishi Yalamarty, Pranava Gande, Kevin Zhang, Ellie Sang, Wei Tse Li, Jessica Wang-Rodriguez, Weg Ongkeko. A multi-omics analysis correlating intratumoral microbial abundance with methylation patterns in hepatocellular carcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 6523.

Hydride Generation-Based Purification Method for High-Precision Antimony Isotopic Analysis in Low-Concentration and Complex-Matrix Samples.

Antimony (Sb) isotopes have emerged as a powerful tool for tracing Sb sources and understanding their geochemical behavior in different systems. However, accurate and precise determination of Sb isotopic compositions (δ123Sb) in natural samples remains a challenge, especially in low-concentration samples with complex matrices. In this study, we introduce a novel two-step purification method for high-precision Sb isotope analysis. In the first step, hydride generation (HG) is employed to effectively isolate Sb from major elements, followed by further purification with a thiol silica column. After optimization, two distinct HG purification modes were established: a flow mode for water samples and a no-flow mode for solid geological samples. Our method achieved complete Sb purification recovery with effective removal of matrix elements and the procedure blank was under the detection limits (<0.1 ng). Moreover, the HG purification process is rapid, requiring only 1 h for a 1 L water sample and 1.5 h for a 1 g geological sample. Application of this method to Sb standard solutions and geochemical reference samples yielded δ123Sb values in excellent agreement with the reference data, confirming that no isotopic fractionation occurred during the HG purification. Finally, we successfully applied this technique to a range of low-Sb environmental samples, including river, seawater, and sediments, demonstrating its effectiveness in accurate and precise Sb isotopic analysis. Overall, this novel method offers a rapid and efficient purification strategy for high-precision Sb isotopic analysis, thereby enhancing our ability to investigate Sb isotopic reservoirs associated with biogeochemical cycles.

Lab-on-Robot: Unmanned Mass Spectrometry Robot for Direct Sample Analysis in Hazardous and Radioactive Environments.

Onsite, safe, and reliable mass spectrometry (MS) analysis of hazardous and radioactive samples plays a crucial role in timely chemical emergency management and response in real environments. The current study reports the development of a smart MS robot by integrating miniature MS, quadruped robot, switchable robotic arm sampler, and direct ionization for remote-controlled chemical analysis of complex samples in inaccessible hazardous and radioactive environments. High automation and excellent analytical performance have been achieved in the real-time analysis of volatile toxic substances in air and onsite detection of explosive particles in air aerosols. Successful detection of hazardous compounds has been performed from raw wastewater. The chemical analysis of radioactive ore samples has also been demonstrated. Low limits of detection at ng/g or ng/mL (signal-to-noise ratio, S/N = 3) and good relative standard deviation (RSD < 12.0%, n = 6) were obtained by the MS robot for analyzing different gaseous, aerosol, liquid, and solid samples. The remote detection results of the MS robot were further validated. The reported study encourages the future development of a smart lab-on-robot, which functions with smart operation to replace the traditional laboratory procedures for MS analysis of dangerous chemical and environmental samples.

Room Temperature Operation of All-Solid-State Potassium-Ion Battery Enabled by Unconventional Ionic Solid Electrolyte K6[Rh4Zn4(l-cys)12O]·nH2O.

The unconventional ionic solid, K6[Rh4Zn4(L-cys)12O]·nH2O, exhibited excellent formability as well as high ionic conductivity. These features enabled a straightforward assembly of all-solid-state potassium-ion battery: A cold-pressed solid sample of K6[Rh4Zn4(L-cys)12O]·nH2O, which was sandwiched by solid samples of K2Ni[Fe(CN)6] and chloranil as cathode, and anode, respectively, displayed an initial discharge capacity of 21.6 mAh g-1-electrodes at 25°C at a current density of 0.5mA cm-2 (∼0.34C). Energy dispersive X-ray spectroscopy analysis confirmed that K+ ions swiftly conduct through K6[Rh4Zn4(L-cys)12O]·nH2O between the cathode and anode during charge-discharge cycles.

Cortisone Analysis by FTIR Spectroscopy: In Vitro Study

Cortisol, known as the “stress hormone”, is vital for stress response, metabolism regulation, and immune function, and salivary cortisone reflects serum cortisol levels. The measurement of salivary cortisone levels has been proposed as an effective alternative method for estimating serum cortisol levels. Objective: This study aimed to evaluate the use of Fourier Transform Infrared Spectroscopy (FTIR) for salivary cortisone identification and quantification and to assess the impact of adding the surfactant TWEEN 80 to the analysis. Methods: Initially, cortisone was diluted in chloroform and methanol (5,000,000 µg/dL). FTIR spectra were obtained, and absorbance characteristics and peaks were identified. The spectrum of this initial dilution was processed using the Savitzky-Golay filter to evaluate peak heights at 1655 cm−1 and 1700 cm−1, and the effect of signal processing on these peaks was assessed. Additionally, two series of dilutions were performed by adding the surfactant TWEEN 80 at two different concentrations, and the effect of the surfactant on the cortisone spectra was evaluated to reduce noise and enhance the signal. Results: The spectra obtained from the cortisone solution were similar to those found in the literature for solid samples. The peak corresponding to the wavenumber range of 1600–1680 cm−1, related to the stretching bands of C=C, was found to be reliable for use in cortisone quantification studies. The standard deviation between the spectra of the same sample was less than 0.01. It was not possible to detect cortisone when TWEEN 80 was added; however, with signal processing, TWEEN 80 could be detected in quantities as low as 0.0033% of the solution. Conclusions: FTIR demonstrates potential as a non-invasive method for cortisone analysis. While Tween 80 aids in the dilution of cortisone in water, it obscures its spectrum.

The Effect of Color Contrast on the Visual Clarity of Images of Complex Indoor Environments

Color contrast creates visual interest, increases attention, and enhances legibility in the indoor environment. Past studies have suggested that color contrast enhances visual clarity due to the color opponency mechanism of the visual system, especially when two opposing colored samples are seen side by side, such as red–green or yellow–blue. However, these studies were limited to solid single-colored samples, which falls short on representing the built environment with its complex distributions of colors and objects. This study explores the validity of the “color contrast–visual clarity” hypothesis for complex images of indoor built environments. Twenty images of indoor environments were selected from an image database to represent a wide range of colorfulness and spatial complexity (ranging from simple to complex). Forty new images were generated by increasing the colorfulness of either the red and green or blue and yellow sections of the original 20 images using an image editing software. Forty participants assessed the visual preference, clarity, colorfulness, and complexity of the 60 images. No statistically significant difference was found between red–green or yellow–blue enhanced images and original images. However, an observable trend indicated a linear relationship between visual clarity and colorfulness. In addition, participants preferred saturated images over original images. While the findings suggest potential trends, the lack of significant effects warrants cautious interpretation, and further research is needed to explore the impact of color contrast in more controlled settings.

The impact of molecular weight on the segregative phase separation-induced molecular fractionation of aqueous gum Arabic/xanthan mixtures.

The impact of molecular weight on the segregative phase separation-induced molecular fractionation of aqueous gum Arabic/xanthan mixtures.

Modeling the stress–strain behavior of municipal solid waste samples under varying temperatures

Modeling the stress–strain behavior of municipal solid waste samples under varying temperatures

Long-term monitoring of plant diversity data in the "Montagna di Torricchio" Strict Nature Reserve, Italy.

Long-term monitoring of plant diversity data in the "Montagna di Torricchio" Strict Nature Reserve, Italy.