Phospholipid polymers water-soluble

Sakai-Kato, K., Kato, M., Ishihara, K. and Toyo-oka, T. (2004) An enzyme immobilization method for integration of biofunctions on a microchip using a water-soluble amphiphilic phospholipid polymer having a reacting group. Lab on a Chip, 4, 4—6. 

Cytocompatible Polymer Hydrogels Composed of Water-Soluble Phospholipid Polymers... 

Kimura M, Fukumoto K, Watanabe J et al (2005) Spontaneously forming hydrogel from water-soluble random- and block-type phospholipid polymers. Biomaterials 26 6853-6862... 

Nam KW, Watanabe J, Ishihara K (2002) Characterization of the spontaneously forming hydrogels composed of water-soluble phospholipid polymers. Biomacromolecules 3 100-105... 

Konno T, Ishihara K (2007) Temporal and spatially controllable cell encapsulation using a water-soluble phospholipid polymer with phenylboronic acid moiety. Biomaterials 28 1770-1777... 

Since the fatty acid chains in each lipid were 18 carbons and 16 carbons, respectively, it is reasonable that they could form a mixed lipid phase. Furthermore the bis-dienoyl substitution of 15 favors the formation of crosslinked polymer networks. Ohno et al. showed that the dienoyl group associated with the sn-1 chain could be polymerized by lipid soluble initiators, e.g. AIBN, whereas the dienoyl in the sn-2 chain was unaffected by AIBN generated radicals. Conversely, radicals from a water-soluble initiator, e.g. azo-bis(2-amidinopropane) dihydrochloride (AAPD), caused the polymerization of the sn-2 chain dienoyl group, but not the sn-1 chain. These data provide clear evidence for the hypothesis of Lopez et al. that the same reactive group located in similar positions in the sn-1 and sn-2 chains of polymerizable 1,2-diacyl phospholipids are positionally inequivalent [23]. 

As noted in Section HE, both layers decrease the absorption rate, especially of large water-soluble molecules, since the diffusion coefficient is directly proportional to the reciprocal values of both the hydrodynamic radius and the viscosity of the layers. About the influence of absorption enhancers on mucus rheology very little is known. Bib salts and phospholipids are known to reduce the viscoelasticity of bronchial mucus aid probably also of mucus layers in the gastxointestinal tract [40. Hie results should be interpreted with caution since it is not the observed macro )viscosity that determines the diffusion rate in polymer... 

The key to long-term physical stability of aqueous nanosuspensions is the selection of a suitable water-soluble surfactant or polymer as an external particle stabilizer to prevent particle growth. Several potential stabilizers are lecithin, phospholipids, poloxamers, and polysorbates. 

We will show in the following section of this chapter that water-soluble synthetic polymers can be used to modify the phase transition behavior of model biomembranes. In these experiments, 1 mg of dry lipid is dispersed with vigorous shaking in 1 ml of buffer containing 1 mg of the polymer of interest. The transition behavior of the polymer-phospholipid mixture is in all cases compared to that of a control sample of lipid hydrated in the absence of polymer. 

The interaction of water soluble polymers with lamellar dispersions has implications in many practical applications such as consumer products, drug delivery, bioseparations, and industrial processes. The osmotic stress method for studying membrane biophysics involves the addition of water soluble polymers such as poly (ethylene glycols) (PEGs) to phospholipid vesicles and measuring the changes in... 

Ahmed M, Bhuchar N, Ishihara K, Narain R (2011) Well-controlled cationic water-soluble phospholipid polymer-DNA nanocomplexes for gene delivery. Bioconjug Chem... 

In our previous studies, we have succeeded in spontaneous gelation of water-soluble phospholipid polymers from their aqueous solutions by hydrogen bonding without any physical treatments (2-7). Also, the hydrogel formed could be dissociated by change in pH, however, the pH inside of the hydrogel was low (pH<4), which would be required in order for its application as a cell container. 

In this study, we synthesized a new water-soluble phospholipid polymer containing a p-vinylphenylboronic acid unit, that is, poly[MPC-co- -BMA-co-/ -vinylphenylboronic acid (VPBA)](PMBV). Also, we reported the synthesis and characterization of the polymer, formation and properties of polymeric hydrogel with PVA, and behavior of fibroblast cells in the hydrogel. 

Both water-soluble and water-insoluble phospholipid polymers containing VPBA were synthesized by the conventional radical polymerization. The water-solubility of polymers depended on the MPC mole fraction in polymer. The chemical structure and synthetic results of polymers are summarized in Figure 2 and Table 1. 

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