Nanoparticles lipid-functionalized

Muller, R.H., Ruhl, D., Runge, S., Schulze-Forster, K., and Mehnert, W., Cytotoxicity of solid lipid nanoparticles as a function of the lipid matrix and the surfactant, Pharmaceutical Research, 1997, 14, 458-462. 

CNTs and other nano-sized carbon structures are promising materials for bioapplications, which was predicted even previous to their discovery. These nanoparticles have been applied in bioimaging and drag delivery, as implant materials and scaffolds for tissue growth, to modulate neuronal development and for lipid bilayer membranes. Considerable research has been done in the field of biosensors. Novel optical properties of CNTs have made them potential quantum dot sensors, as well as light emitters. Electrical conductance of CNTs has been exploited for field transistor based biosensors. CNTs and other nano-sized carbon structures are considered third generation amperometric biosensors, where direct electron transfer between the enzyme active center and the transducer takes place. Nanoparticle functionalization is required to achieve their full potential in many fields, including bio-applications. 

New functions can be obtained by modifications of SLNs. Incorporation of Tween 80 and Poloxamer 188 can stabilize SLNs to achieve long-circulating or crossing blood-brain barrier effects [112], Recently, novel nanoparticles called polymer-lipid hybrid nanoparticles (PLNs) were developed [113]. They can entrap cationic anticancer agents (e.g., doxorubicin) effectively by incorporation of an anionic lipophilic polymer into lipids to treat multidrug-resistant (MDR) cancers. 

Therefore, of great importance seems to be the creation of CdS/Cu S heterojunctions, which penetrate the lipid membrane and function simultaneously as both photosensitizers of a photocatalytic process and as electron carriers through the vesicle membrane. An intermediate step in the development of approaches to the formation of such heterojunctions is the synthesis of Cu S nanoparticles in the outer or inner surface of the membrane. 

As a new type of electron relay, which is able to penetrate lipid membranes, we tested menaquinone (MQ, Fig. 7). Compounds of this type were not utilized earlier for artificial vesicle-based systems. However, these mimick the functioning of the Z-scheme of natural plant photosynthesis (see Figs 9 and 12). Indeed, the activity of MQ in the redox processes in a lipid bilayer membrane was revealed. However, the quantum yield of the transmembrane electron transfer from a CdS nanoparticle in the inner cavity to a CdS nanoparticle on the outer membrane surface with the participation of MQ appeared to be very low and did not exceed 0.2-0.4%. 

Salvador-Morales, C., Zhang, L., Langer, R., Farokhzad, O. Immunocompatibility properties of lipid-polymer hybrid nanoparticles with heterogeneous surface functional groups. Biomaterials 2009, 30 (12), 2231-2240. 

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