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Three-dimensional (3D) dried blood spheroids formed on hydrophobic paper are a new microsampling platform that can stabilize labile molecules in whole blood stored in ambient air at room temperature. In this study, we define the ideal conditions for preparing the dried blood spheroids. The physical morphology of 3D dried blood spheroids is found to be largely impacted by the unregulated relative humidity of the surrounding environment. A solution of KOH placed in an enclosed chamber offers a facile way to control humidity. We also report a general polymer coating strategy that serves to stabilize dried biofluids when prepared under ordinary ambient conditions without regulation of humidity. Dried blood spheroids coated in xanthan gum polymer exhibited enhanced chemical and physical stability. The same xanthan gum polymer provided chemical stability for 2D dried blood spots when compared with the conventional noncoated samples. We have expanded the application of xanthan gum to less viscous biofluids such as urine to induce an artificial protective barrier that also provides enhanced stability for labile performance-enhancing drugs stored at room temperature. The impact of polymer coating on direct biofluid analysis via paper spray mass spectrometry was determined by comparing the relative ionization efficiency, percent difference of ionization efficiency, and matrix effects of performance-enhancing drugs that were spiked in undiluted raw urine. Acceptable analytical performance was recorded for all three criteria, including high ionization efficiencies that ranged from 77 to 93% in the presence of the xanthan gum polymer.

The ability to measure the concentration of metabolites in biological samples is important, both in the clinic and for home diagnostics. Here we present a nanopore‐based biosensor and automated data analysis for quantification of thiamine in urine in less than a minute, without the need for recalibration. For this we use the Cytolysin A nanopore and equip it with an engineered periplasmic thiamine binding protein (TbpA). To allow fast measurements we tuned the affinity of TbpA for thiamine by redesigning the π‐π stacking interactions between the thiazole group of thiamine and TbpA. This substitution resulted furthermore in a marked difference between unbound and bound state, allowing the reliable discrimination of thiamine from its two phosphorylated forms by residual current only. Using an array of nanopores, this will allow the quantification within seconds, paving the way for next‐generation single‐molecule metabolite detection systems., Quantification of small molecules in biological samples is challenging. Using the concentration‐dependent current fluctuations elicited by a thiamine binding protein inside a ClyA nanopore, we show the automated quantification of thiamine in urine in less than a minute. By swapping the internal biosensor, this principle can be applied for the development of multiple next‐generation home‐diagnostic small‐molecule sensors.

Long non-coding RNAs (lncRNAs) are a heterogeneous group of transcripts that lack protein coding potential and display regulatory functions in various cellular processes. As a result of their cell- and cancer-specific expression patterns, lncRNAs have emerged as potential diagnostic and therapeutic targets. The accurate characterization of lncRNAs in bulk transcriptome data remains challenging due to their low abundance compared to protein coding genes. To tackle this issue, we describe a unique short-read custom lncRNA capture sequencing approach that relies on a comprehensive set of 565,878 capture probes for 49,372 human lncRNA genes. This custom lncRNA capture approach was evaluated on various sample types ranging from artificial high-quality RNA mixtures to more challenging formalin-fixed paraffin-embedded tissue and biofluid material. The custom enrichment approach allows the detection of a more diverse repertoire of lncRNAs, with better reproducibility and higher coverage compared to classic total RNA-sequencing.

The collection of liquid biological matrices onto paper cards (dried matrix spots [DMS]) is becoming an alternative sampling strategy. The stability over time of molecules of interest for therapeutic, sport drug monitoring, and forensic toxicology on DMS has been recently investigated representing a reliable alternative to conventional analytical techniques. When a tampering of a urine sample in drug monitoring or doping control cases is suspected, it could be relevant to know whether genetic profiles useful for individual identification could be generated from urine samples spotted onto paper (dried urine spot [DUS]). To understand the influence of sex, storage conditions, and time on the quality and quantity of the DNA, five female and ten male urine samples were dispensed onto Whatman 903 paper and sampled after different storage conditions over time, from 1 to 12 weeks. Direct PCR was performed starting from 2-mm punches collected from each spot amplifying a panel of markers useful for individual identification. The female DUS stored in different conditions produced genetic profiles fully matching the reference samples. The same result was obtained for the male DUS but using urine 30X concentrated by centrifugation instead of the original samples. Our data show that this approach is valid for genetic individual identification of urine samples spotted onto paper cards up to 12 weeks after deposition and could be easily incorporated in anti-doping or drug screening protocols to help on the suspicion of evidence tampering or to solve questions on the reliability of samples collection.

In this study, a heat-resistant and high-wettability lithium-ion batteries separator (PI-CPM-PI) composed of cellulose nanofibers (CNF) and aramid fibers (PMIA chopped fiber/PPTA pulp) with the reinforced concrete structure was fabricated via a traditional heterogeneous paper-making process. CNF played crucial roles in optimizing the pore structure and improving the wettability of PI-CPM-PI separator. The effects of composition on separator properties were investigated and the results indicated that the optimal compositions were 0.5 wt% CNF, 0.5 wt% PMIA chopped fiber/PPTA pulp (ratio of 5:5), 0.05 wt% diatomite and 1.5 wt% polyimide. Relevant tests demonstrated that the performance advantages of PI-CPM-PI separators were exhibited at the wettability and thermal stability compared to the commercial separator (PP). Additionally, batteries assembled with PI-CPM-PI separators showed excellent electrochemical and cycling performance (ionic conductivity of 1.041 mS.cm

BACKGROUND: The results of urine tests are often affected by improper midstream urine collection time, urine spilling, and urine pollution, all of which can lead to an increase in the test error. OBJECTIVE: To solve this problem, aiming at improving the toilet environment at the hospitals and public physical examination centers, this paper designs an automatic urine collection system. It can automatically adjust the position of the urine cup with an infrared remote controller, or manually, adjust the position of the urine cup in special situations according to the needs of the user. It also has an alarm function. METHODS: The overall size and shape are designed based on the squatting pan, suitable for disposable plastic urine cups of different shapes and sizes. It can realize the automatic collection of midstream urine, manual collection in exceptional cases, emergency stops, and rescue calls. RESULTS: Through the trial survey, there was a significant difference between the statistical results of using the device and not using the device (t= 13.937, P= 0.000). 96% of the subjects thought that the design of the system was reasonable, 22% thought that it was inconvenient to use, and 91.7% of the medical staff thought that the system met the sampling requirements. CONCLUSIONS: Therefore, the trial evaluation is satisfactory, and the proposed collection system is suitable for use in hospitals at all levels and public health examination centers with a large amount of inspection.

The rapid and sensitive detection of ultra-trace marker molecules from biological samples is of great significance for the wide application of surface-enhanced Raman spectroscopy (SERS) methods in clinical diagnosis and disease monitoring. However, the cumbersome biological sample processing procedures and the poor enrichment of target analytes in hot spots hinder the practical applications of SERS methods. In this paper, we synthesized a novel floating SERS substrate by a simple one-step oxidation process, annealing and

This paper presents ISFET array based pH-sensing system-on-ultra-thin-chip (SoUTC) designed and fabricated in 350 nm CMOS technology. The SoUTC with the proposed current-mode active-pixel ISFET circuit array is desined to operate at 2V and consumes 6.28 W per-pixel. The presented SoUTC exhibits low sensitivity to process, voltage, temperature and strain-induced (PVTS) variations. The silicon area occupancy of each active-pixel is 44.9x33.5 m2 with an ion-sensing area of 576 m2. The design of presented ISFET device is analysed with finite element modeling in COMSOL Multiphysics using compact model parameters of MOSFET in 350 nm CMOS technology. Owing to thin (~30m) Si-substrate the presented SoUTC can conform to curvilinear surfaces, allowing intimate contact necessary for reliable data for monitoring of analytes in body fluids such as sweat. Further, it can operate either in a rolling shutter fashion or in a pseudo-random pixel selection mode allowing the simultaneous detection of pH from different skin regions. Finally, the circuits have been tested in aqueous Dulbeccos Modified Eagle Medium (DMEM) culture media with 5-9 pH values, which mimics cellular environments, to demonstrate their potential use for continuous monitoring of body-fluids pH.

A battery’s charging data include the timing information with respect to the charge. However, the existing State of Health (SOH) prediction methods rarely consider this information. This paper proposes a dilated convolution-based SOH prediction model to verify the influence of charging timing information on SOH prediction results. The model uses holes to fill in the standard convolutional kernel in order to expand the receptive field without adding parameters, thereby obtaining a wider range of charging timing information. Experimental data from six batteries of the same battery type were used to verify the model’s effectiveness under different experimental conditions. The proposed method is able to accurately predict the battery SOH value in any range of voltage input through cross-validation, and the SDE (standard deviation of the error) is at least 0.28% lower than other methods. In addition, the influence of the position and length of the range of input voltage on the model’s prediction ability is studied as well. The results of our analysis show that the proposed method is robust to different sampling positions and different sampling lengths of input data, which solves the problem of the original data being difficult to obtain due to the uncertainty of charging–discharging behaviour in actual operation.

Centrifugal microfluidic platforms (CDs) have opened new possibilities for inexpensive point-of-care (POC) diagnostics. They are now widely used in applications requiring polymerase chain reaction steps, blood plasma separation, serial dilutions, and many other diagnostic processes. CD microfluidic devices allow a variety of complex processes to transfer onto the small disc platform that previously were carried out by individual expensive laboratory equipment requiring trained personnel. The portability, ease of operation, integration, and robustness of the CD fluidic platforms requires simple, reliable, and scalable designs to control the flow of fluids. Valves play a vital role in opening/closing of microfluidic channels to enable a precise control of the flow of fluids on a centrifugal platform. Valving systems are also critical in isolating chambers from the rest of a fluidic network at required times, in effectively directing the reagents to the target location, in serial dilutions, and in integration of multiple other processes on a single CD. In this paper, we review the various available fluidic valving systems, discuss their working principles, and evaluate their compatibility with CD fluidic platforms. We categorize the presented valving systems into either “active”, “passive”, or “hybrid”—based on their actuation mechanism that can be mechanical, thermal, hydrophobic/hydrophilic, solubility-based, phase-change, and others. Important topics such as their actuation mechanism, governing physics, variability of performance, necessary disc spin rate for valve actuation, valve response time, and other parameters are discussed. The applicability of some types of valves for specialized functions such as reagent storage, flow control, and other applications is summarized.

Sensing of key parameters in fluidic environments has attracted extensive attention because the physical features of body fluids could be used for point-of-care disease diagnosis. Although various sensing methods have been investigated, effective sensing strategies of microenvironments remains a major challenge. In this paper, we propose an approach that can realize sensing of fluidic viscosity and ionic strength using microswarms formed by simple colloidal nanoparticles. The influences of fluidic ionic strength and viscosity on two swarm behaviors are analyzed (i.e., the spreading of circular vortex-like swarms and the elongation of elliptical swarms). The data models for quantifying the fluidic viscosity and ionic strength are obtained from experiments, and the fluidic features can be sensed successfully using the swarm behaviors. Furthermore, we demonstrate that the microswarms have the capability of passing through tortuous and narrow microchannels for sensing. Continuous sensing of different fluidic environments using swarms is also realized. Finally, the sensing of viscosity and ionic strength of porcine whole blood is presented, which also validates the feasibility of the sensing strategy.

Melibiose-derived AGE (MAGE) is an advanced glycation end-product formed in vitro in anhydrous conditions on proteins and protein-free amino acids during glycation with melibiose. Our previous studies revealed the presence of MAGE antigen in the human body and tissues of several other species, including muscles, fat, extracellular matrix, and blood. MAGE is also antigenic and induces generation of anti-MAGE antibody. The aim of this paper was to identify the proteins modified by MAGE present in human body fluids, such as serum, plasma, and peritoneal fluids. The protein-bound MAGE formed in vivo has been isolated from human blood using affinity chromatography on the resin with an immobilized anti-MAGE monoclonal antibody. Using mass spectrometry and immunochemistry it has been established that MAGE epitope is present on several human blood proteins including serum albumin, IgG, and IgA. In serum of diabetic patients, mainly the albumin and IgG were modified by MAGE, while in healthy subjects IgG and IgA carried this modification, suggesting the novel AGE can impact protein structure, contribute to auto-immunogenicity, and affect function of immunoglobulins. Some proteins in peritoneal fluid from cancer patients modified with MAGE were also observed and it indicates a potential role of MAGE in cancer.

Point-of-Care (POC) testing for biomarker detection demands techniques that are easy to use, readily available, low-cost, and with rapid response times. This paper describes the development of a fully open-source, modular, wireless, battery-powered, smartphone-controlled, low-cost potentiostat capable of conducting electrochemical impedance spectroscopy for the electrochemical detection of the S100B protein captured in an ANTI-S100B functionalized thin-film gold interdigitated electrode platform to support traumatic brain injury diagnosis and treatment. EIS results from the developed potentiostat were validated with a commercial benchtop potentiostat by comparing impedance magnitude and phase values along the EIS frequency range. In addition, an experimental design was performed for detecting S100B in spiked human plasma samples with S100B concentrations of clinical utility, and a calibration curve was found for quantifying S100B detection. No statistically significant differences were found between EIS results from the developed potentiostat and the commercial potentiostat. Statistically significant differences in the changes in charge transfer resistance signal between each tested S100B concentration (p < 0.05) were found, with a limit of detection of 35.73 pg/mL. The modularity of the proposed potentiostat allows easier component changes according to the application demands in power, frequency excitation ranges, wireless communication protocol, signal amplification and transduction, precision, and sampling frequency of ADC, among others, when compared to state-of-the-art open-source EIS potentiostats. In addition, the use of minimal, easy acquirable open-source hardware and software, high-level filtering, accurate ADC, Fast Fourier Transform with low spectral leakage, wireless communication, and the simple user interface provides a framework for facilitating EIS analysis and developing new affordable instrumentation for POC biosensors integrated systems.

The association of body fluids/cell types and donors in mixed biological traces is an important, but challenging task required to evaluate the value of evidence given forensic propositions concerning the source of the DNA. The linking of a DNA profile with evidence from presumptive tests or RNA analysis is not straightforward. Coding region SNPs (cSNPs) are a novel type of evidential markers that are both cell type specific and individual specific. They thereby provide a direct link between a donor and a body fluid in mixed biological stains. In this proof-of-concept paper we consider the evaluation of cSNP profiles given source level propositions and explore the use of the open-source software EuroForMix to compute likelihood ratios. The discrimination power of the cSNPs for various body fluids is investigated with simulations. We provide case examples where the type of biological material is questioned and where cSNP profiles can be used to assign a donor to a body fluid, and discuss how the results can be reported in court.

Three disposable stochastic sensors using nanolayer deposition of a graphene nanocomposite comprising graphene nanoparticles and gold nanoparticles, on different supports: silk, plastic, and paper, and modified with chitosan, were characterized and validated for molecular recognition and quantification of maspin in biological samples. Very low limits of determination (of pg mL

In recent years, RNA profiling has become an important technique in identifying the origin of human body fluids/tissues. Both perpetrators and victims can be identified from stains involving vaginal secretions (VS), such as sperm/VS mixtures left on condoms, bed sheets, or papers, etc. Body fluid specific RNA typing could link the source of body fluids/tissues and the identity of the donor. In this study, we aimed to trace the donor of VS in mixture stains using body fluid-specific mRNA markers and construct a coding single nucleotide polymorphism (cSNP) typing system for VS. We screened 8 VS-specific mRNA biomarkers (MUC4, SFTA2, CYP2A6, MYOZ1, FUT6, ESR1, SPINK5, and SERPINB13) encompassing 18 cSNPs. The RNA obtained from various body fluid/tissue samples was treated with reverse transcription polymerase chain reaction (RT-PCR) and then followed by a multiplex PCR and SNaPshot mini-sequencing assay. The detection limit of the assay was 0.08 ng RNA. For single-source body fluid, the positive cSNP typing was only shown in VS and void in non-VS body fluids/tissues. For laboratory-generated VS-containing mixtures, the minor VS contributor could be successfully detected at a ratio of 1:10-1:500. We also confirmed the concordance of DNA typing and mRNA typing for the cSNPs in this system. In summary, we established an 18-cSNP typing system for VS with high sensitivity and specificity, which could identify both the donor and the tissue origin simultaneously. This was shown to be a powerful tool for identifying the VS donor in those VS-containing mixture stains.

Estimating the contact angle of a virus infected saliva droplet is seen to be an important area of research as it presents an idea about the drying time of the respective droplet and in turn of the growth of the underlying pandemic. In this paper we extend the data presented by Balusamy, Banerjee and Sahu [“Lifetime of sessile saliva droplets in the context of SARS-CoV-2,” Int. J. Heat Mass Transf. 123, 105178 (2021)], where the contact angles are fitted using a newly proposed half-circular wrapped-exponential model, and a sequential confidence interval estimation approach is established which largely reduces both time and cost with regards to data collection.

Live anthrax vaccine containing spores from attenuated strains STI-1 of Bacillus anthracis is used in Russia and former CIS (Commonwealth of Independent States) to prevent anthrax. In this paper we studied the duration of circulation of antibodies specific to spore antigens, the protective antigen (PA), the lethal factor (LF) and their domains (D) in donors’ blood at different times after their immunization with live anthrax vaccine. The relationship between the toxin neutralization activity level and the level of antibodies to PA, LF and their domains was tested. The effect of age, gender and number of vaccinations on the level of adaptive post-vaccination immune response has been studied. It was shown that antibodies against PA-D1 circulate in the blood of donors for 1 year or more after immunization with live anthrax vaccine. Antibodies against all domains of LF and PA-D4 were detected in 11 months after vaccination. Antibodies against the spores were detected in 8 months after vaccination. A moderate positive correlation was found between the titers of antibodies to PA, LF, or their domains, and the TNA of the samples of blood serum from the donors.