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In this paper, we propose a microfluidic approach for measuring pH, dissolved oxygen (O2), and carbon dioxide (CO2) in human saliva. The proposed innovative method combines the advantages of a microfluidic approach, i.e., small amounts of samples and reagents and precise control of the experimental conditions, with rapid measurements of significant parameters of saliva. The novel design of a microfluidic chip with integrated commercially available PreSens sensors was used for examining the effect of Chlorhexidine on artificial saliva (AS), stimulated saliva (SS), and non-stimulated saliva (NSS). The measurement results showed that for persons with an initially low saliva pH, the use of Chlorhexidine increased the pH, and afterward, the pH value returned to the initial value or higher. However, measurements of volunteers with initial pH close to neutral showed that Chlorhexidine reduced the pH value, increasing the risk of erosion and demineralization. In conclusion, the proposed methodology showed potential for precise measurements of pH in saliva samples; however, further research is required to examine the influence of the sample collection method on the amounts of O2 and CO2 in saliva. [ABSTRACT FROM AUTHOR]

Miniaturization of different measurement processes and a scaled-down approach open the possibility for rapid measurements with the small amounts of samples and reagents into a compact platform with integrated sensors and different measuring components. In this paper, we report a microfluidic approach for measurements of salivary pH, dissolved O2, and CO2 during chewing xylitol gum. The study was done with the samples of 30 healthy volunteers who were chewing a xylitol gum, and the measurements were performed in the microfluidic (MF) chip with integrated commercial PreSens sensors. Xylitol exhibited a significant effect on the pH of saliva in terms of its initial drop, which was the most significant between the 5th and 10th minutes. The effect of xylitol on the amount of oxygen and carbon dioxide in saliva cannot be confirmed. The employed microfluidic platform was shown to be applicable and effective in the analysis of salivary biomarkers relevant to caries development. [ABSTRACT FROM AUTHOR]

Copper(II) phthalocyanine (CuPc), also known as Pigment Blue 15, is a widely utilized pigment renowned for its exceptional semiconducting properties when refined to electronic-grade purity. Recent studies have confirmed its safety if ingested at doses required for essential active components in edible electronics for advanced gastrointestinal tract monitoring. Since in-body operations impose stringent safety constraints on operational biases, the development of transistors with high transconductance at low voltages is required to ensure adequate amplification gain. This study presents a simple and cost-effective method for producing solution-processed CuPc films characterized by a unique porous microstructure that facilitates efficient volumetric ion uptake and mixed ionic-electronic conductivity in electrolyte-gated devices. These porous films exhibit capacitance 30 times greater than compact CuPc films produced through conventional physical vapor deposition methods. The resulting edible transistors demonstrate On/Off ratios exceeding 10 3 and channel width-normalized transconductance of up to 50 µS mm -1 at 0.8 V, establishing their potential as critical active components in future edible devices. Moreover, the proposed method results in a limited impact of impurities on CuPc charge transport efficiency, thus affecting the purification costs and, crucially, enabling the sourcing of CuPc pigments through recycling and upcycling., (© 2025 The Author(s). Advanced Science published by Wiley‐VCH GmbH.)

Purpose: The purpose of this study was to quantify the elastic properties and evaluate microscopical features of raw and boiled metatarsal bovine bone., Methods: The elastic modulus, hardness and microscopic surface of raw and cooked bovine metatarsal bone have been investigated using nanoindentation, SEM/EDX and Panasis microscope., Results: Regarding raw bovine bone, the average elastic modulus was 30.515 ± 6,769 GPa, while the average hardness was 0.5683 ± 0.211 GPa. When it comes to boiled bone corresponding values were 22.298 ± 7.0303 GPa and 0.408 ± 0.199 GPa, respectively. The values for investigated parameters were significantly higher (p < 0.05) in raw bone specimens. Elastic modulus significantly correlated with hardness (p < 0.05). EDX analysis revealed significant decrease in wt% of oxygen in boiled samples (p < 0.05) No significant differences could be observed in SEM images particularly when analysing in smaller magnifications. Using higher magnification, additional branching of the existing voids as well as discrete reorganization and smoother edges of nutrient canals could be observed. The surface of boiled specimens was without the presence of crusts and layering, and no microscopical evidence of structural damage could be observed., Conclusions: This study provides detailed analysis of hardness, elastic modulus of raw and cooked bovine bone and their relation and changes during exposure to temperature. These results of elastic moduli and hardness could be comparable to similar studies of bovine and human bone tissue, but the careful analysis of experimental design, type of the bone as well as limitations of the employed techniques must be carried out before interpolation of the results to other theoretical, clinical, biomaterial and archeological studies.