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The concept of reducing the analysis time with the bulk sensors operating in nonequilibrium mode is formulated theoretically and verified experimentally with ion-selective polymeric optodes. The influence of the measurement time on the optical response range, span, median, and sensitivity is calculated and demonstrated experimentally. Model aqueous samples are successfully analyzed using a nonequilibrium measurement protocol with conventional sodium-selective optodes and with pH optodes containing lipophilic organic electrolyte. The analysis time is significantly reduced from 300 to ca. 100 s, with sufficient recovery, reproducibility, and precision of the sample determination.

The application of spheroids in tissue engineering has a number of advantages over conventional cell suspensions and 2D cultures. One of the methods for tissue and organ fabrication from spheroids is bioprinting. As one of bioprinting methods, laser-induced forward transfer (LIFT) has received much attention in terms of cell printing, while its potential has not been realized for spheroid patterning yet. In this paper, the authors have shown for the first time the practical applicability of LIFT for spheroid transfer with high survival rates and printing precision. For this, a special optical device, a piShaper, was used to change the laser energy distribution to non-Gaussian profile which allowed for mitigating the negative effects of laser radiation on the spheroids during LIFT. The authors showed that non-Gaussian energy distribution in the laser spot in the form of double ring led to higher post-printing viability of spheroids than in case of conventional Gaussian energy distribution in laser beam. Subsequently, using the double ring laser spot geometry, the spheroids were bioprinted in the form of simple geometric figures: line, triangle, and square. Overall, LIFT bioprinting of spheroids has demonstrated a strong potential as the precise, safe, and reproducible method for biofabrication that can be potentially used for making tissue-engineered bioequivalents or building specific organ-on-a-chip platforms.

A novel way of synthesis is developed for the Ba2+selective neutral Ionophore 2a: 2,2′‐[1,2‐phenylenebis(oxyethane‐2,1‐diyloxy)]bis(N‐benzyl‐N‐phenylacetamide) and its methyl (2b), buthyl (2c), and hexyl (2d) derivatives. Ba2+selective electrodes based on Ionophores 2a–dare compared with those with commonly used Ionophore 1: N,N,N′,N′‐tetracyclohexyl‐oxybis(o‐phenyleneoxy) diacetamide. It is shown that Ionophores 2a–d, particularly 2b, are superior for measurements of Ba2+in the presence of Ca2+, and in acidic solutions. Segmented sandwich membrane studies suggest formation of complexes IL22+for Ba2+, Ca2+and Mg2+ions with Ionophore 2b, while H+ions apparently form complexes H2L2+. The values of the complex formation constants are consistent with the selectivity coefficients.

We report here a simple and cost-effective technique for classification of the samples of writing inks based on their digital color analysis (DCA). The dynamics of artificial aging of writing inks under UV irradiation was studied by means of DCA for the first time. The color of ballpoint pen marks was recorded over time using an ordinary consumer DSLR camera. The inks were classified according to the parameters of their color degradation curves with precision superior to conventional Raman scattering method, which serves as a proof-of-concept of the proposed approach. The reported approach has broad prospects for implementation by criminalists for document investigation when document forgery is suspected. The proposed technique can be of interest not only in the field of forensic science but also for those who deal with dyes and dye-containing materials and their degradation over time as well as for the study of any processes, the evolution of which is reflected in a color change.