Micelles biomedical applications

Jeffamine M-1000 increases the pH and hemolytic activities [34]. Modifying the side chains with amino acids valine, leucine, and phenylalanine imparts pH-responsive properties onto the polymer, which could be useful for many biomedical applications [36]. Polymers with PEG side chains have been developed into micelles and show enhanced uptake in spheroids formed with HeLa cells [37]. These polymers have also been conjugated to fluorescent dyes, which could be used for drug-tracking applications [38,39]. 

Poly(L-lysine)-Based Copolymers Synthetic Strategies and Biomedical Applications 115 Charged biopharmaceuticals PIC micelle... 

In this contribution we intend to provide a eomprehensive review on PLA stereo-complex, including preparation, strueture-properties and biomedical applications. The effect of stereo-complex on the thermal dynamics, hydrolytic degradation, micellization and hydrogelation will be discussed. 

Over 40 years since it what found that phospholipids can form closed bilayered structures in aqueous systems, liposomes have made a long way to become a popular pharmaceutical carrier for numerous practical applications. Liposomes are phospholipid vesicles, produced by various methods from lipid dispersions in water. Liposome preparation, their physicochemical properties and possible biomedical application have already been discussed in several monographs. Many different methods exist to prepare liposomes of different sizes, structure and size distribution. The most frequently used methods include ultrasonication, reverse phase evaporation and detergent removal from mixed lipid-detergent micelles by dialysis or gel-filtration. To increase liposome stability towards the physiological environment, cholesterol is incorporated into the liposomal membrane (up to 50% mol). The size of liposomes depends on their composition and preparation method and can vary from... 

Micellization of polydiene copolymers was examined by Petrak and co-workers [ 165] in the case of PEO-PI-PEO for the development of controlled drug release systems. This interest in biomedical applications was also the starting point for extensive studies on micellar systems obtained with PEO-poly(amino acid) [166, 167], PEO-polyesters block copolymers [168, 169] and PEO-poly (ethylacrylate) [170]. PEO-poly(methylidene malonate), also designated by PEO-PMM 212, of the following structure were developed in our group ... 

Micelle formation with amphiphilic graft and comb copolymers has received much less attention than that of block copolymers, although brush structures are gaining interest, mainly for biomedical applications (see Section 7.4). As already mentioned in Section 7.2, this is mainly due to the fact that these branched copolymers are not as well defined in structure, composition and molecular weight as the corresponding block copolymer, even if they are synthesized by controlled polymerization and macromonomer techniques. 

The most interesting situation is that where the complex formation occurs between two block copolymers A-B and A-C, respectively C-D, with specific interactions between the blocks B and C (see Figure 7.8, scheme (c)), such PIC, also called block ionomer complexes (BIC) have been studied quite extensively in aqueous medium by Harada and Kataoka [270] and by Kabanov and Alakhov [271] due to their practical interest in controlled delivery systems. Kataoka and co-workers have for instance shown that water-soluble PlCs for biomedical applications are formed by combination of PEO-poly(L-lysine) and PEO-poly (a, /3-aspartic acid). These authors have further demonstrated that the PIC micelles prepared under charge-neutralized conditions have an extremely narrow size distribution if matched pairs of copolymers with the same block lengths of polyanions and polycations are combined [272]. 

For biomedical applications, which will only be considered in this review, it could be mentioned that Kataoka and co-workers [327] prepared non-fouling surfaces by coating them with core-polymerized PEG-PLA block copolymer micelles having an aldehyde-ended PEG shell. 

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