Phospholipid polymers system

Similarly to the phospholipid polymers, the MPC polymers show excellent biocompatibility and blood compatibility [43—48]. These properties are based on the bioinert character of the MPC polymers, i.e., inhibition of specific interaction with biomolecules [49, 50]. Recently, the MPC polymers have been applied to various medical and pharmaceutical applications [44-47, 51-55]. The crosslinked MPC polymers provide good hydrogels and they have been used in the manufacture of soft contact lenses. We have applied the MPC polymer hydrogel as a cell-encapsulation matrix due to its excellent cytocompatibility. At the same time, to prepare a spontaneously forming reversible hydrogel, we focused on the reversible covalent bonding formed between phenylboronic acid and polyol in an aqueous system. 

Oki, A., Adachi, S., Takamura, Y., Ishihara, K., Kataoka, K., Ichiki, T., Honike, Y., Glucose measurement in blood serum injected by electroosmosis into phospholipid polymer coated microcapillary. Micro Total Analysis Systems, Proceedings of the 4th IJ.TAS Symposium, Enschede, Netherlands, May 14-18, 2000, 403-406. 

In the field of biomimetic chemistry, phospholipid molecules have been utilized for the preparation of cell membrane-like stractures, namely, liposomes and Langmuir-Blodgett membranes. However, a major disadvantage of molecular assemblies of this kind is their inadequate chemical and/or physical stability. Stabilization of the phospholipid assembly is therefore an important topic of focus in the construction of interfaces between living and artificial systems. One approach to addressing this issue is the design of a new type of polymer system with PC groups. 

The response of blomolecules and cell membranes Is determined by many factors, some of which are the chemical composition and conformation of the molecules, the surface energy, and topography of the top surface layers which are in contact with biological systems, I.e., body fluids and cells [45]. The work illustrated here consisted In designing new polymers with functional properties capable of promoting the attachment of specific cells. The first step consisted in a polymer system which surface inhibits non-specific cell attachment. This strategy is based on the incorporation of cell membrane constituents such as phosphorylcholine (PC) or phospholipid analogues into polymers [46-51]. 

Ye, S.H. et al., Novel cellulose acetate membrane blended with phospholipid polymer for hemocompatible filtration system. Journal of Membrane Science, 2002. 210(2) 411-121. 

Many complex systems have been spread on liquid interfaces for a variety of reasons. We begin this chapter with a discussion of the behavior of synthetic polymers at the liquid-air interface. Most of these systems are linear macromolecules however, rigid-rod polymers and more complex structures are of interest for potential optoelectronic applications. Biological macromolecules are spread at the liquid-vapor interface to fabricate sensors and other biomedical devices. In addition, the study of proteins at the air-water interface yields important information on enzymatic recognition, and membrane protein behavior. We touch on other biological systems, namely, phospholipids and cholesterol monolayers. These systems are so widely and routinely studied these days that they were also mentioned in some detail in Chapter IV. The closely related matter of bilayers and vesicles is also briefly addressed. 

A further partihon system based on the use of liposomes, and commercialized under the name Transil [110, 111], has shown its utiUty as a UpophiUcity measure in PBPK modeling [112]. Fluorescent-labeled liposomes, called fluorosomes, are another means of measuring the rate of penetration of small molecules into membrane bilayers [113, 120]. Similarly, a colorimetric assay amenable to HTS for evaluating membrane interactions and penetrahon has been presented [116]. The platform comprises vesicles of phospholipids and the chromahc Upid-mimehc polydiacetylene. The polymer undergoes visible concentrahon-dependent red-blue transformahons induced through interactions of the vesicles with the studied molecules. 

Multiplex CARS microspectroscopy, in conjunction with appropriate spectral analysis tools, was successfully applied to the study of phospholipid bilayer model systems [120, 121, 142, 70, 143], lipids within cells [144, 127, 145-147, 141], a single pollen grain [148], a single bacterial endophore [140], a molecular J-aggregate microcrystal [149], silicon components on a wafer [130], separated phases in polymer blends [123, 135], and concentration profiles in a microreactor [150]. 

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