Interaction aggregation

Numerous studies reported the in vitro interaction of lipoplexes with serum (14). The parameters checked, such as maintained lipid-DNA interactions, aggregate formation, zeta potential changes, or DNA morphological changes, did not allow for consistent prediction of in vitro transfection efficiency of lipoplexes in serum (15). However, it is obviously an indication of poor delivery of DNA at the target site. 

Jiang Xi-Kui (1988) Hydrophobic-lipophilic interactions. Aggregations and self-coiling of organic molecules. Accts Chem Res 21 362- 367... 

Denaturation of whey proteins has been shown to unfold their polypeptide chains and convert thexx conformation from a globular to an extended form that facilitates their self interaction (aggregation) and interaction with K-casein by disulfide interchange, ionic and hydrophobic bonding (4). 

Considerable effort has been spent to explain the effect of reinforcement of elastomers by active fillers. Apparently, several factors contribute to the property improvements for filled elastomers such as, e.g., elastomer-filler and filler-filler interactions, aggregation of filler particles, network structure composed of different types of junctions, an increase of the intrinsic chain deformation in the elastomer matrix compared with that of macroscopic strain and some others factors [39-44]. The author does not pretend to provide a comprehensive explanation of the effect of reinforcement. One way of looking at the reinforcement phenomenon is given below. An attempt is made to find qualitative relations between some mechanical properties of filled PDMS on the one hand and properties of the host matrix, i.e., chain dynamics in the adsorption layer and network structure in the elastomer phase outside the adsorption layer, on the other hand. The influence of filler-filler interactions is also of importance for the improvement of mechanical properties of silicon rubbers (especially at low deformation), but is not included in the present paper. 

ADAMs are membrane proteins that contain a disintegrin and a metalloprotease domain. Disintegrins are RGD-containing proteins that inhibit cell/matrix interactions (adhesion) and cell/cell interactions (aggregation) through the integrin receptors. In addition, ADAMs have two other domains that are involved in signaling and transport (113). 

Adsorption and desorption data points are presented in Figures 2-4 and are well matched with linear, least-squares fit isotherms, namely, 6 vs. Ceq plots. Linear isotherms are expected for situations having low surface coverage such as ours (seen in very low values of 6 exhibited by the data), where the probability of adsorbate-adsorbate interactions (aggregation) is small. It is conceivable that actual variation of 0 with Ceq may be more complex than a linear function however, data scatter is such that more detailed analysis of adsorption-desorption data is not justified. In any case, linearity, as characterized by I.T slope on the log-log plots, fits the data quite well. These plots are required for presentation of data that span six orders of magnitude in each direction. 

For light scattering experiments, the choice of the laser is critical. Natural organics can be fluorescent compounds when excited by lower laser wavelengths. This interferes with measurements. This effect can be minimised by the choice of a red laser. Additionally, given the low concentrations required to avoid molecule interactions, aggregation or multiple scattering of these small compounds, a very powerful laser is required. 

Increases in mass transfer rates have been obtained before (Lye and Stuckey, 2001) with similar systems but interfacial convection had not been observed and the explanation put forward was that the increase in rates was caused by an interaction/aggregation between the surfactant and the solute at the interface. 

Protein interactions. Aggregation of globular proteins. Discussions Faraday Soc. 13 (1953) 170-176. 

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