There is great need for stand-alone luminescence-based chemosensors that exemplify selectivity, sensitivity, and applicability and that overcome the challenges that arise from complex, real-world media. Discussed herein are recent developments toward these goals in the field of supramolecular luminescent chemosensors, including macrocycles, polymers, and nanomaterials. Specific focus is placed on the development of new macrocycle hosts since 2010, coupled with considerations of the underlying principles of supramolecular chemistry as well as analytes of interest and common luminophores. State-of-the-art developments in the fields of polymer and nanomaterial sensors are also examined, and some remaining unsolved challenges in the area of chemosensors are discussed.

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Supramolecular Luminescent Sensors

Effects of ultrasound on the thermal and structural characteristics of proteins in reconstituted whey protein concentrate

SUMMARY The ban on the use of antibiotics in feeds as growth promoters in many countries throughout the world has increased the incidence of enteric disorders in poultry. Natural additives, inclusion of whole cereals, feeding coarse mash diets, and increasing the level of fiber in the diets have been explored as nutritional strategies to reduce the incidence of the problem. Traditionally, dietary fiber has been considered a diluent of the diet and, often, an antinutritional factor. However, moderate amounts of fiber might improve the development of organs, enzyme production, and nutrient digestibility in poultry. Some of these effects are a consequence of better gizzard function, with an increase in gastroduodenal refluxes that facilitate the contact between nutrients and digestive enzymes. These effects often result in improved growth and animal health, but the potential benefits depend to a great extent on the physicochemical characteristics of the fiber source. In conclusion, poultry require a minimal amount of fiber in the diet for proper functioning of the digestive organs. The response to fiber inclusion depends on the source and level of dietary fiber and the characteristics of the diet as well as on the physiological status and health of the bird. In particular, the inclusion in the diet of moderate amounts of coarse, insoluble fiber sources, such as oat hulls, at levels between 2 and 3% usually improves the growth performance of broilers fed low-fiber diets.

Poultry response to high levels of dietary fiber sources varying in physical and chemical characteristics

Viscosity B-coefficients and standard partial molar volumes of amino acids, and their roles in interpreting the protein (enzyme) stabilization

The multifunctional nucleocapsid (N) protein in SARS-CoV-2 binds the ~30 kb viral RNA genome to aid its packaging into the 80-90 nm membrane-enveloped virion. The N protein is composed of N-terminal RNA-binding and C-terminal dimerization domains that are flanked by three intrinsically disordered regions. Here we demonstrate that the N protein's central disordered domain drives phase separation with RNA, and that phosphorylation of an adjacent serine/arginine rich region modulates the physical properties of the resulting condensates. In cells, N forms condensates that recruit the stress granule protein G3BP1, highlighting a potential role for N in G3BP1 sequestration and stress granule inhibition. The SARS-CoV-2 membrane (M) protein independently induces N protein phase separation, and three-component mixtures of N + M + RNA form condensates with mutually exclusive compartments containing N + M or N + RNA, including annular structures in which the M protein coats the outside of an N + RNA condensate. These findings support a model in which phase separation of the SARS-CoV-2 N protein contributes both to suppression of the G3BP1-dependent host immune response and to packaging genomic RNA during virion assembly.

/pdf/the-sars-cov-2-nucleocapsid-phosphoprotein-forms-mutually-6lugvmsj21.pdf

The SARS-CoV-2 nucleocapsid phosphoprotein forms mutually exclusive condensates with RNA and the membrane-associated M protein.

In this work, we present experimental results for partial molar volumes and viscosities of aqueous solutions of α-dl-aminobutyric acid, dl-norvaline and dl-norleucine at 288.15, 293.15, 298.15 and 303.15 K. The thermodynamic behavior of aqueous amino acid solutions is compared with that reported for glycine and α-alanine in water and is discussed in terms of group additivity and electrostriction. The temperature dependence of the infinite dilution partial molar volumes and the B viscosity coefficients are interpreted in terms of amino acid hydration. According to the usual hydrophobicity criteria, the amino acids considered do not have a hydrophobic character and their behavior is dominated by the polar groups.

Effect of temperature on partial molar volumes and viscosities of aqueous solutions of α-dl-Aminobutyric acid, dl-Norvaline and dl-Norleucine

A comparative study of the volumetric properties of dilute aqueous solutions of 1-propanol, 1,2-propanediol, 1,3-propanediol, and 1,2,3-propanetriol at various temperatures

Carmen M. Romero

Papers

Effect of temperature on partial molar volumes and viscosities of aqueous solutions of α-dl-Aminobutyric acid, dl-Norvaline and dl-Norleucine

A comparative study of the volumetric properties of dilute aqueous solutions of 1-propanol, 1,2-propanediol, 1,3-propanediol, and 1,2,3-propanetriol at various temperatures

Apparent molal volumes and viscosities of dl-α-alanine in water–alcohol mixtures

An improved method for isolation of β-lactoglobulin

Osmotic and activity coefficients of glycine, dl-α-alanine and dl-α-aminobutyric acid in aqueous solutions at temperatures between 288.15 and 303.15 K