Characterization of electrostatic interactions and complex formation of ɣ-poly-glutamic acid (PGA) and ɛ-poly-l-lysine (PLL) in aqueous solutions
In this study, we examined the possibility of using anionic ɣ-poly-glutamic acid (PGA) and cationic ɛ-poly-L-lysine (PLL) to form polyelectrolyte complexes. Initially, the formation and properties of the complexes were characterized using visual observations, UV-visible spectrophotometry, microelectrophoresis (ζ-potential), and isothermal titration calorimetry (ITC). The impact of pH, ionic strength, temperature, and polymer ratio on complex formation was examined. The electrostatic complexes formed had a 1:4 mass ratio of polyanion-to-polycation at saturation (pH 7.4). The surface potential and aggregation stability of the complexes was highly dependent on solution pH (2 to 12), which was attributed to alterations in the electrical characteristics of the two polyelectrolytes. In particular, insoluble complexes were formed under pH conditions where there was a strong electrostatic attraction between the two polyelectrolytes, whereas soluble complexes were formed when there was only a weak attraction. The addition of salt (≥ 20 mM NaCl) promoted aggregation of the complexes, presumably due to screening of the electrostatic interactions between them. Conversely, temperature (25 to 90 oC) did not have a major impact on the stability of the complexes. These results may be useful for the design of effective oral delivery systems for bioactive agents in foods and other products.Graphical abstract
Authors: Karimi G, Vard B, Riyahi R, Motlagh ME, Heshmat R, Kelishadi R Abstract This cross-sectional study was conducted among 14,400 Iranian students, aged 7-18 years to determine the association between the frequency of family dinner and mental health. Family dinner frequency, family relationship, life satisfaction (LS), self-perceived health and anxiety were assessed by validated questionnaires. Of 14,274 participants, 50.6% were boys and 71.4% were urban residents, with a mean (SD) age of 12.28 (3.16) years. Family dinner frequency was significantly correlated with LS (boys: β = 0.27, p
In this study we explored the use of a natural compound rubusoside (RUB) as a solubilizer to enhance the solubility of a fluorescence-labeled C6-Ceramide (NBD C6-Ceramide) and to characterize its pharmacokinetics and tissue distribution in an animal model. RUB significantly enhanced the solubility of NBD C6-Ceramide by forming nanomicelles, and efficiently delivered NBD C6-Ceramide in rats by oral and intravenous administration. RUB loaded 1.96% of NBD C6-Ceramide in the nanomicelles and solubilized it to a concentration of 3.6 mg/mL in water. NBD C6-Ceramide in nanomicelles remained stable in aqueous solutions, all...
Publication date: Available online 10 December 2019Source: Prostaglandins &Other Lipid MediatorsAuthor(s): Giorgio Mottola, Evan Werlin, Bian Wu, Mian Chen, Anuran Chatterjee, Melinda Schaller, Michael S. ConteAbstractInflammation ensuing from vascular injury promotes intimal hyperplasia (IH) and restenosis. Resolvin D1 (RvD1) is a lipid mediator that attenuates IH in vivo when delivered locally to the vessel wall in animal models. We tested the hypothesis that peri-procedural oral administration of RvD1 could blunt the local inflammatory response to angioplasty, and attenuate downstream IH. Carotid angioplasty was per...
First-of-its-kind trial evaluates decision aid’s efficacy
Authors: Glauser W PMID: 31818934 [PubMed - in process]
Authors: Owens B PMID: 31818933 [PubMed - in process]
Authors: Dermer M, Martel J, Greenhill A PMID: 31818932 [PubMed - in process]
Authors: Robson R PMID: 31818931 [PubMed - in process]
Authors: Lamb S PMID: 31818930 [PubMed - in process]
Authors: Zimmer V, Glanemann M, Lammert F PMID: 31818929 [PubMed - in process]