Acryloyl-lipids

All four types of polymerizable lipids shown in Fig. 4 have been realized synthetically. In this context, one need not attempt to reproduce mother nature slavishly (Fendler 8)). Kunitake 9) was able to show that simple molecules like dialkyldimethyl-ammonium salts also form bilayer assemblies. Fuhrhop 10) and Kunitake U) could accomplish the formation of monolayer liposomes with molecules containing only one alkyl chain and two hydrophilic head groups. Acryloylic and methacryloylic groups (type a and d, Table 1), as well as diacetylenic, butadienic, vinylic and maleic acid groups (type b and c), have been used as polymerizable moieties. A compilation of amphiphilic, photopolymerizable molecules is given in Table 1. 

In the case of butadienic lipids, the polyreaction was followed by a decrease of the strong monomer absorption (260 nni)25). Disappearance of vinyl protons in the 2H NMR spectrum proved polymer formation for vesicles made from vinylic, acryloylic, and methacryloylic surfactants l3,16). 

In the HBMs described above, enhanced stability derives from multivalent inter-molecular interactions among linear lipo-polymers in the outer monolayer, relative to the fewer number of interactions expected per monomer in an unpolymerized HBM. An alternative strategy is to link covalently the lipid tail(s) to the inner monolayer, as described by Krishna et al. [60], They used a four-step approach to create poly(acrylatePC) coatings on silicone catheters (Fig. 3) (1) plasma polymerization of allyl alcohol on the catheter surface (2) reaction with acryloyl chloride (3) vesicle fusion of monoacryloyl-terminated lipids on the acryloyl functionalized... 

In contrast to diacetylenes, lipids with alkene-functionalized chains (e.g., acryloyl, dienoyl) can be polymerized in the La phase to a high degree of conversion [74], O Brien and coworkers systematically studied polymerization of acryloyl and dienoyl lipids in bilayer vesicles (see [25,26] for reviews). Subsequently, the Saavedra and O Brien groups prepared and characterized solid supported bilayers composed of dienoyl lipids (Fig. 6) [11, 75-77], Several parameters relating... 

The acidic form of classical sophorolipid (a deacetylated compound) produced by alkaline hydrolysis of the native lactonic form (Fig. 2) was successfully converted by enzymatic biotransformation (glycosidase catalysis) to an acidic glucose lipid [44]. Another modification was performed with alkyl-amines leading to alkylamides of the acidic sophorolipid [123]. Bisht et al. [128] reported an efficient chemoenzymatic route that led to an 6-O-acryloyl-sophorolipid macrolactone analog. The homopolymerization of this monomer as well as its copolymerization with acrylic acid and acrylamide led in maximum to a molecular weight of 4.2 x 10" Da. The first total synthesis of a major component of the microbial classical lactonic sophorolipid was described by Fiirstner et al. [129]. 

Andersson M, Oscarson S (1993) Synthesis of glycoconjugates by covalent coupling of o-glycopyranosyl-n-hydroxysuccinimide derivatives of lactose to proteins and lipids and polymerization of their parent acryloyl derivatives into acrylamide polymers. Bioctmjug Chem 4(3) 246-249... 

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