Poly(ornithine-co-citrulline)s are ureido-based polymers, which were shown to exhibit tunable upper critical solution temperature (UCST) behavior, a property that can be exploited develop thermoresponsive nanoparticles for controlled drug delivery systems. To gain insight into the driving forces govern formation and dissolution processes of poly(ornithine-co-citrulline) nanoparticles, molecular...

Objectives: To evaluate the corrosion inhibition of an ethanolic extract Portulaca quadrifida (PQ) leaves on carbon steel surface in well-water by using a weight-loss study with various immersion periods, temperatures, and pH. The kinetic thermodynamic parameters are calculated for temperatures. Methods: protective film has been analyzed SEM, EDX AFM studies. action PQ was potentiodynamic polar...

Ex situ conservation of ferns may be accomplished by maintaining the viability of stored spores for many years. Storage conditions that maximize spore longevity can be inferred from an understanding of the behaviour of water within fern spores. Water sorption properties were measured in spores of five homosporeous species of ferns and compared with properties of pollen, seeds, and fern leaf tis...

– A tensile blob construction for branched structures is used to explain structural sizes larger than the strand length, as observed in neutron scattering data from equilibrium swollen networks. Under this model, equilibrium swollen networks display a base structural size, the “gel tensile blob” size, ξ, that follows the scaling relationship ξ ∼ l/(1/2−χ)P , where l is the monomer length, χ is ...

To characterize the thermodynamical equilibrium of DNA chains interacting with a solution of nonspecific binding proteins, we implemented a Flory-Huggins free energy model. We explored the dependence on DNA and protein concentrations of the DNA collapse. For physiologically relevant values of the DNA-protein affinity, this collapse gives rise to a biphasic regime with a dense and a dilute phase...

In present investigation new formulations of Sodium Alginate/Acrylic acid hydrogels with high porous structure were synthesized by free radical polymerization technique for the controlled drug delivery of analgesic agent to colon. Many structural parameters like molecular weight between crosslinks (Mc ), crosslink density (Mr ), volume interaction parameter (v2,s ), Flory Huggins water interact...

1. Introduction The formation of miscible mixtures of two chemically dissimilar polymers is in general unfavourable. For many materials a single phase is never formed, while for others, the miscible state is only obtained at low temperatures. The classic description of the interaction between two polymers is via the Flory-Huggins theory (for example see [l]) in which x, the interaction paramete...

Colonic mucus is a key biological hydrogel that protects the gut from infection and physical damage and mediates host-microbe interactions and drug delivery. However, little is known about how its structure is influenced by materials it comes into contact with regularly. For example, the gut abounds in polymers such as dietary fibers or administered therapeutics, yet whether such polymers inter...

The moisture sorption isotherm of pea starch films prepared with various glycerol contents as plasticizer was investigated at different storage relative humidities (11%-96% RH) and at 5 ± 1, 15 ± 1, 25 ± 1 and 40 ± 1 °C by using gravimetric method. The results showed that the equilibrium moisture content of all films increased substantially above aw = 0.6. Films plasticized with glycerol, under...