The phase behavior of aqueous mixtures of gelatin and oligosaccharides above their gelation temperature is investigated experimentally, and rationalized according to a simple multicomponent Flory–Huggins model. When the gelatin is only weakly charged, entropic considerations dominate and it is found that the cloud point curve of the mixtures is extremely sensitive to the molecular weight distri...

Lung surfactant lowers surface tension and adjusts interfacial rheology to facilitate breathing. A novel instrument, the interfacial stress rheometer (ISR), uses an oscillating magnetic needle to measure the shear viscosity and elasticity of a surfactant monolayer at the air-water interface. The ISR reveals that calf lung surfactant, Infasurf, exhibits remarkable fluidity, even when exposed to ...

The effects of an anionic surfactant, sodium dodecyl sulphate (SDS), on the optical transmittance, thermal, and rheological properties of methylcellulose (MC) aqueous solutions have been studied. The particular interest of this work was focused on the effects of SDS on the sol–gel transition of MC. Basically, two effects of SDS have been identified, which are the salt-out and salt-in effects at...

The in situ formation of injectable silk fibroin (SF) hydrogels have potential advantages over various other biomaterials due to the minimal invasiveness during application. Biomaterials need to gel rapidly under physiological conditions after injection. In the current paper, a novel way to accelerate SF gelation using an anionic surfactant, sodium dodecyl sulfate (SDS), as a gelling agent is r...

Lipoteichoic acids (LTAs) of varying chemical composition from five streptococcal species and one lactobacillus species initiated gelation of Limu lus amebocyte lysate. Preincubation with antisera specific for the poly(glycerol phosphate) (PGP) chain or, when appropriate, with antisera, specific for a carbohydrate substituent inhibited gelation initiated by lipoteichoic acid, but did not inhibi...

The thermoreversible gelation of methylcellulose in aqueous solution has been studied by static and dynamic light scattering (DLS), small-angle neutron scattering (SANS), and rheology. At 20 °C, dilute solution light scattering establishes the molecular weight, second virial coefficient, radius of gyration, and hydrodynamic radius of the polymer. Semidilute solutions exhibit two relaxation mode...

There is a medical need for robust, biocompatible hydrogels that can be rapidly crosslinked in situ through the use of gentle and non-toxic triggers, which could be used as a surgical adhesive, a bone-inductive material, or for drug and gene delivery. The complete gelation system described here includes calcium-loaded liposomes, hrFactor XIII. thrombin, and an enzymatic substrate based on a fou...

By William A. Eaton, James Hofrichter, and Philip D. Ross T HE FACTORS which determine the frequency of crises and overall severity in sickle cell disease are still not clear. Although Allison,’ Charache and Conley,2 and others3’4 have considered that the kinetics of sickling may be important clinically, accurate measurements of the rates of hemoglobin S gelation and cell sickling have only bee...

the present work investigated the preparation of biodegradable beads with alginate polymer by ionotropic gelation method to improve the control release properties of the antibiotic rifampicin. ionotropic gelation method was applied to prepare beads using calcium chloride (cacl2) as cationic component and alginate as an anionic component. in this method, adding 0.5% w/v polyvinyl alcohol (pva) t...