Transport through liquid membranes generated by lecithin-cholesterol mixtures

Biomimetic Gallstone Formation: Crystallization of Calcium Carbonate by the Evolving Taurocholate−Lecithin−Cholesterol Complex Lipid System

“…Further fusion of unilamellar vesicles resulted in 200-500 nm multilamellar vesicles (liquid crystals). Later, more cholesterol (cmc ) 30.08 × 10 -9 M) 42 started to precipitate out in hydrate and anhydrous forms giving solid crystals of different shapes, such as platelets, arcs, needles, filaments, spirals, helices, and tubules. 30,54 Cholesterol monohydrate appeared more rapidly than anhydrous cholesterol because the taurocholate to lecithin ratio was 2.9 e 7.0.…”

“…Further fusion of unilamellar vesicles resulted in 200−500 nm multilamellar vesicles (liquid crystals). Later, more cholesterol (cmc = 30.08 × 10 −9 M) started to precipitate out in hydrate and anhydrous forms giving solid crystals of different shapes, such as platelets, arcs, needles, filaments, spirals, helices, and tubules. , Cholesterol monohydrate appeared more rapidly than anhydrous cholesterol because the taurocholate to lecithin ratio was 2.9 ≤ 7.0 . The whole microscopic structural evolution of the complex system mentioned above followed a so-called Pathway C. , As cholesterol was being crystallized, taurocholate and lecithin in the sludge might begin to form taurocholate micellar aggregates, lecithin multilamellar vesicles, and taurocholate−lecithin mixed micelles simultaneously as summarized by us schematically based on refs and (Figure ).…”

“…Gallstone is a composite material of organic and inorganic components. Much of the attention to gallstone formation has still been paid to the prerequisites of the other organic components and complex fluid structures in gallbladder bile, including cholesterol and its solubilization, − bile salt micellar aggregation, − phospholipid vesiculation, − cholesterol−phospholipid vesiculation, − bile salt−phospholipid mixed micelle formation, − and bile salt−cholesterol−phospholipid mixed vesiculation. , Yet, there are a few papers addressing the contributions , of calcium ions and calcium carbonate phase on cholesterol nucleation, , calcium carbonate−cholesterol interactions, , calcium−phospholipid bindings, and calcium−bile salts interactions. − …”

Studies of Cellulose Acetate Supported Ergosterol Liquid Membrane

“…When a surfactant is added to a membrane, the transmission characteristics of membrane is modified due to formation of immobilized structure [19,20]. Surfactants are amphipathic compounds.…”

Development of urethane acrylate composite ion-exchange membranes and their electrochemical characterization

“…5, which may be responsible for the increase in membrane conductance and membrane potential when composite AEMs were operated in the solution of HCOONa, CH 3 COONa, or CH 3 CH 2 COONa. Enhanced membrane potential and membrane conductance values for different sodium carboxylate solutions in comparison to NaCl may be due to (i) lower dissociation of homologues of higher carboxylates resulting in lower concentration of Na + than expected (it is well known that in ion-exchange membranes, ion selectivity will increase with the decrease in counterion concentration because of enhanced co-ion exclusion [24]) and/or (ii) partial adsorption of negatively charged carboxylate ions which may be due to their mild surface activity resulting in increased net surface charge density of the composite CEM and which is responsible for enhanced ion selectivity [25]. When the electrolyte solution contains large organic ions, such as CH 3 (CH 2 ) 4 COONa or CH 3 (CH 2 ) 7 COONa, the large organic ions adsorb selectively onto the membrane surface and permeate through the membrane slowly.…”