Enhanced interaction with membrane

Fullerene showed antibacterial activity, which can be attributed to different interactions of C60 with biomolecules (Da Ros et al., 1996). In fact, there is a possibility to induce cell membrane disruption. The fullerene sphere seems not really adaptable to planar cellular surface, but for sure the hydrophobic surface can easily interact with membrane lipids and intercalate into them. However, it has been demonstrated that fullerene derivatives can inhibit bacterial growth by unpairing the respiratory chain. There is, first, a decrease of oxygen uptake at low fullerene derivative concentration, and then an increase of oxygen uptake, which is followed by an enhancement of hydrogen peroxide production. The higher concentration of C60 seems to produce an electron leak from the bacterial respiratory chain (Mashino et al., 2003). 

NaCIO is an acknowledged novel absorption enhancer for ampicillin sodium [99], glycyr-rhizin [100,101], gentamicin [102], phenoxymethyl penicillin [103], cefoxitin sodium [104,105], and acyclovir [106], Takahashi et al. [107] reported that the enhanced membrane permeability of phenolsulfonphthalein depends on the disappearance kinetics of CIO from the loop and its calcium ion sequestration capacity. The enhancing mechanisms of NaCIO are proposed to be involved in (1) Ca2+ sequestration, (2) increase in pore size and solvent drag, (3) interaction with membrane proteins and lipids, and (4) increase in the intracellular calcium level [104,105,108-111],... 

By increasing the hydrophobicity of plasmids and reducing their net negative surface charge, PVP may facilitate the uptake of plasmids by muscle cells. Intramuscular injection of PVP-based plasmid formulations in rats significantly increased the number and distribution of expressing cells, as compared to unformulated plasmid. The formation of condensed interpolyelectrolyte complexes between PVP and DNA has been proposed to both protect DNA from nuclease degradation and facilitate its cellular uptake by hydrophobic interaction with cell membranes. The increased hydrophobicity of the complex may enhance interaction with cell membranes and facilitate cell uptake. 

Their biological activity is based on their interaction with membrane phospholipids [8, 9] resulting in increased excretion of glutamate and in enhanced uptake of various substances through stomata. Besides the membrane damaging effect tensides influence markedly the activity of enzymes [10] and enhance the biological activity of insecticides [11] by improving their solubility. 

In a more fundamental vein, Zhang et al. [157] studied the confined crystallization behavior of PLA/acetylated BC nanocomposites prepared by compression molding. The results indicated that acetylated BC favored the crystallization of PLA at higher temperatures. In a similar mode, Quero et al. [158] investigated the micromechanical properties of laminated BC/PLA nanocomposites by Raman spectroscopy as a mean to understand the fundamental stress-transfer processes in these nanocomposites and as a tool to select appropriate processing and volume fraction of the fibers. Results showed that Young s modulus and stress at failure of PLA films were foimd to increase by 100 and 315%, respectively, for 18% volume fraction of BC and BC membranes cultured for 3 days exhibited enhanced interaction with PLA because of their higher total surface area. 

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