BioScientia (Poland)

Cassie-Baxter superhydrophobic surfaces repel aqueous media by trapping a thin air layer known as plastron. However, current methods to estimate plastron characteristics on such surfaces, either directly through digital still imaging/confocal microscopy or indirectly through contact angle goniometry, are technically challenging and often imprecise. Previously, we demonstrated that the solid-liquid area fraction, which quantifies the fraction of the solid surface that is in direct contact with the surrounding liquid, can be accurately measured by reflectance optical microscopy, provided that the material surface has approximately uniform local reflectivity. To eliminate the complexity associated with optical reflectance measurements, we recently demonstrated that the drop adhesion force correlates linearly with the solid-liquid area fraction. In this study, we advance the drop adhesion force measurements obtained at different environments, compression distances, and during pressurization-hold experiments to reveal whether the plastron sustains external pressure or undergoes gradual collapse. Here, we demonstrate that measuring drop adhesion force is a robust, rapid, and technically simple method for assessing plastron properties under a wide range of environmental and surface conditions. The proposed method provides information on plastron stability within minutes and thus could aid in the design of ultrarepellent surfaces with long-term stability in demanding applications.

Superhydrophobic surfaces have attracted considerable attention due to their remarkable ability to repel aqueous media by trapping an air layer. However, estimating the solid-liquid area fraction is challenging due to the complexity of their intrinsic properties and the limited resolution of methods for assessing contact area. We demonstrated that solid-liquid area fraction can be measured using reflectance optical microscopy, which provides a millimeter field of view with a micrometer lateral resolution. However, this method depends on the surface's optical characteristics. To simplify these measurements, this study examines the drop adhesive force as a means of quantifying solid-liquid area fraction. Utilizing a controlled experimental setup, we investigated the relationship between drop adhesive forces and solid-liquid area fraction. After considering various surface geometries obtained by laser and electrochemical treatments, we engineered 23 surfaces with solid-liquid area fractions ranging from 0.1% to ∼50%. Our results show that the adhesive force exerted by droplets on these surfaces increases linearly with the degree of air entrapment beneath the liquid. This provides a measurable indicator of their Cassie-Baxter superhydrophobicity. This research advances our fundamental understanding of plastron on superhydrophobic surfaces, facilitating the development of highly repellent, ultraslippery surfaces.

Inspired by nature, chemically fueled reaction cycles provide a general strategy to couple the dissipation of chemical potential to controlled changes in molecular structure, assembly, and material function. Here, we review how kinetically stable yet thermodynamically activated fuels, catalytic activation–deactivation cycles, and supramolecular transformations integrate into a common design spanning molecular, assembly, and material length scales. We unify terminology across communities using diverse systems into state-network descriptions that capture reciprocal coupling between chemical and supramolecular states. Central to function is kinetic asymmetry (feedback from the supramolecular state on reaction rates), which biases reaction flux and enables work-like behavior, including directional motion, adaptive lifetimes, self-healing, oscillations, bistability, and spatiotemporal control of optical, mechanical, and catalytic properties. By contrasting single-point versus multipoint activation and intramolecular versus intermolecular processes, we extract practical design principles and highlight open challenges, including quantitative kinetic descriptions at the assembly scale, management of waste accumulation under sustained fueling, and scaling chemo-mechanical coupling toward higher-order autonomous systems. Overall, this review provides a shared mechanistic language and a set of transferable guidelines for engineering functional, adaptive, chemically powered systems across all length scales.

Feline leukemia virus (FeLV) significantly impacts feline health worldwide. Although several FeLV antigen rapid tests are available, selecting an accurate diagnostic tool remains a clinical challenge. In this paper, we present a novel and robust point-of-care assay that enables the precise diagnosis of FeLV antigen in blood, plasma, and serum and directly compared it with five other commercially available rapid FeLV antigen tests. Among the evaluated assays, Vet Expert and SNAP demonstrated 100% sensitivity, specificity, and accuracy, equaling gold-standard performance. Results demonstrate Vet Expert’s superior diagnostic accuracy and practical applicability in both veterinary practice and disease control strategies.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12985-025-03015-y.

Capillary blood microsampling enables the sampling of small blood volumes, making it suitable for vulnerable populations, remote collection, and repeated sampling. Owing to its minimal invasiveness, blood microsampling has emerged as an alternative to venipuncture in many fields. However, as capillary blood differs from venous blood in composition and analytes vary in their distribution between the blood cell and plasma fractions, plasma and capillary blood concentrations may differ. Because plasma is often the standard matrix for routine analyses, this discrepancy can compromise the clinicians' interpretation of capillary blood results. Hence, to ensure comparability with results obtained through plasma-based assays and reference ranges, accurate conversion to plasma concentrations may be required, which may improve the reliability and validity of microsampling-based outcomes. Despite its relevance, guidance on whether conversion is appropriate or desired and on how to translate and validate the translation of capillary blood microsampling results to plasma concentrations is lacking. To address this gap, members of the International Association of Therapeutic Drug Monitoring and Clinical Toxicology (IATDMCT) expert committees have prepared this guideline to discuss the "what, when, and how" of converting capillary to plasma concentrations and provide guidance on the decision of fit-for-purpose conversion. In addition, guidance to assess capillary blood results when the reference matrix is whole blood and to assess liquid capillary plasma results is provided. The included topics, as well as considerations and recommendations presented in this guideline, were based on a previously published dried blood spot-based IATDMCT guideline, literature review and expert opinions of the authors. Key points include the importance of conducting a comprehensive clinical validation study to fully understand capillary blood microsampling results. In addition, the performance of the conversion method should be evaluated case by case, as it depends on both the microsampling-based method and analyte of interest. Furthermore, an independent set of paired capillary and venous samples should be used to validate an established conversion formula. Finally, a key point for future studies is to focus on the clinical impact of (converted) capillary blood concentrations in comparison with decisions based on results in the reference matrix to guarantee any microsampling-based outcome.

Animal preclinical experiments in pulmonary hypertension (PH) need to be conducted with detailed methodological rigor to improve their translational relevance. One of its crucial yet insufficiently studied aspects is animal body weight (BW). Thus, our study aimed to examine the influence of initial BW on the severity of PH development induced by monocrotaline (MCT) and the effectiveness of the reference combined therapy (ambrisentan and tadalafil given for 21 days). Male rats were divided into three weight Sets: Set I (200–219 g); Set II (220–239 g); and Set III (240–259 g), after which, MCT-PH was induced. The measurements taken included in vivo echocardiographic evaluations, ex vivo functional experiments (on isolated right ventricle papillary muscles and pulmonary arteries), and histological and morphometric assessments. In all three Sets of animals, we noticed evidence of PH development. More pronounced changes confirming the severity of PH were observed in Set II compared to Sets I and III. The effectiveness of the reference therapy was also most evident in Set II, where the reversal of PH-related aggravations was best documented. We demonstrated that both the severity of MCT-induced PH in rats and the effectiveness of the reference combined therapy strongly depend on the animals’ initial BW.

Abstract Accuratein-silicoprediction of protein-ligand binding affinity is essential for efficient hit identification in large molecular libraries. Commonly used structure-based methods such as docking often fail to rank compounds effectively, and free energy-based approaches, while accurate, are too computationally intensive for large-scale screening. Existing deep learning models struggle to generalize to new targets or drugs, and current evaluation methods often do not accurately reflect real-world performance. We introduceBALM, a deep learning framework that predictsbindingaffinity using pre-trained protein and ligandlanguagemodels. We also propose improved evaluation strategies with diverse data sets and metrics to assess model performance to new targets better. Using the BindingDB dataset, BALM generalises unseen drugs, scaffolds, and targets. In few-shot scenarios for targets such asUSP7andMpro, it outperforms traditional machine learning and docking methods, including AutoDock Vina. Adoption of our target-based evaluation methods will allow a more stringent evaluation of machine learning-based scoring tools. Our protein prediction framework shows good performance, is computationally efficient, and is highly adaptable within this evaluation setting, making it practical for early-stage drug discovery screening.

ABSTRACTCulture is currently the gold standard for diagnosis of urinary tract infections (UTIs); however, it has poor sensitivity detecting urogenital pathogens, especially if patients have already initiated antimicrobial therapy, or have an infection from an organism that is not commonly cultured. False negative urine culture results can lead to the inappropriate use of antimicrobial therapies or to the progression to urosepsis in high-risk patients. Though not commonly applied to urine in a clinical setting, Next-generation sequencing (NGS)-based metagenomics offer a solution as a precision diagnostic. We developed and validated BIOTIA-ID, a clinical-grade NGS-based diagnostic pipeline for the detection and identification of pathogens in urine specimens. Remnant clinical urine specimens, and contrived sterile urine spiked with common UTI pathogens, were processed with our end-to-end assay including extraction, metagenomic library preparation and Illumina NextSeq 550 sequencing. We trained and applied a bioinformatic pipeline that uses machine learning (ML) to identify pathogens. Internal controls and other quality control measures were incorporated into the process to provide rigorous and standardized results. The assay was tested on 1,470 urine specimens and achieved 99.92% sensitivity, 99.95% specificity and a limit of detection (LoD) of <25,000 CFU/mL and <5,000 CFU/mL in bacteria and fungi, respectively. Discordant results were reconciled with additional testing by target-specific qPCR or 16S Sanger sequencing; 87% of the NGS results were ultimately determined to be the correct result. Overall, these data demonstrate that BIOTIA-ID is a highly accurate clinical-grade diagnostic tool with notable advantages over current culture- based diagnostics.Conflict of Interest StatementMCR, DCD, HLW, SR, XJS, JP, PFC, GF, CEM, CO, NBO and DNS are employees at Biotia, Inc.

Abstract Breast cancer is a global health issue affecting 2.3 million women per year, causing death in over 600,000. Mammography (and biopsy) is the gold standard for screening and diagnosis. Whilst effective, this test exposes individuals to radiation, has limitations to its sensitivity and specificity and may cause moderate to severe discomfort. Some women may also find this test culturally unacceptable. This proof-of-concept study, combining bottom-up proteomics with Matrix Assisted Laser Desorption Ionisation Mass Spectrometry (MALDI MS) detection, explores the potential for a non-invasive technique for the early detection of breast cancer from fingertip smears. A cohort of 15 women with either benign breast disease (n = 5), early breast cancer (n = 5) or metastatic breast cancer (n = 5) were recruited from a single UK breast unit. Fingertips smears were taken from each patient and from each of the ten digits, either at the time of diagnosis or, for metastatic patients, during active treatment. A number of statistical analyses and machine learning approaches were investigated and applied to the resulting mass spectral dataset. The highest performing predictive method, a 3-class Multilayer Perceptron (MLP) neural network, yielded an accuracy score of 97.8% when categorising unseen MALDI MS spectra as either the benign, early or metastatic cancer classes. These findings support the need for further research into the use of sweat deposits (in the form of fingertip smears or fingerprints) for non-invasive screening of breast cancer.

Ion-exchange chromatography is still one of the most popular protein separation techniques. Before chromatographic separation, the high salt concentration in various samples necessitates additional steps. Therefore, low salt tolerance of ion-exchange resins is a drawback that needs to be addressed. Herein, the differences in salt tolerance and hydrophobicity of strong cation-exchange TOYOPEARL resins of sulfonium and sulfate-types were investigated. Despite only a minor structural difference, differences in selectivity and salt tolerance between the sulfate and sulfonic groups were detected. In silico calculations were also carried out for model substances representing the sulfonium and sulfate groups, wherein significant differences in hydrophobicity was observed. These experiments confirmed the hypothesis that the salt tolerance, higher affinity, and selectivity for certain vitamin K dependent clotting factors are interrelated and dependent on the presence of the sulfate group. Separation of clotting factor IX from the prothrombin complex concentrate further to confirmed the affinity for these proteins. The results show that the use of only a resin with the sulfate ligand and not with the sulfonic acid ligand allows for a facile and rapid separation of clotting factor IX and other vitamin K dependent clotting factors.