Non-covalent surface

A number of nanotube surface modification approaches have been reported in the recent years. Non-covalent surface modifications aim to physically wrap polymer chains around the nanotubes or adsorb various surfactant molecules on the surface of nanotubes. Thus,... 

La Saponara and co-workers have demonstrated that the non-covalent surface treatment of the CNTs using hexamethylene diamine and one of two surfactants, (Triton X-100) or cetyl pyridinium chloride (CPC), enabled the production of reinforced fibreglass-reinforced panels, which were prepared with treated CNT/epoxy by hand lay-up. The surface treatment with diamine/CPC resulted in the most superior composites with improved mechanical performance, higher resistance to fatigue and impact damage (over 30... 

Kossovsky N, Anderson S, Gelman A and Sponsler E. Persistent activity of DNase following its non-covalent surface immobilization on... 

Non-covalent interactions between molecules often occur at separations where the van der Waals radii of the atoms are just touching and so it is often most useful to examine the electrostatic potential in this region. For this reason, the electrostatic potential is often calculated at the molecular surface (defined in Section 1.5) or the equivalent isodensity surface as shown in Figure 2.18 (colour plate section). Such pictorial representations... 

As mentioned earlier, adhesive bond formation is governed by interfacial processes occurring between the adhering surfaces. These interfacial processes, as summarized by Brown [13] include (1) van der Waals or other non-covalent interactions that form bonds across the interface (2) interdiffusion of polymer chains across the interface and coupling of the interfacial chains with the bulk polymer and (3) formation of primary chemical bonds between chains or molecules at or across the interface. 

The van der Waals and other non-covalent interactions are universally present in any adhesive bond, and the contribution of these forces is quantified in terms of two material properties, namely, the surface and interfacial energies. The surface and interfacial energies are macroscopic intrinsic material properties. The surface energy of a material, y, is the energy required to create a unit area of the surface of a material in a thermodynamically reversible manner. As per the definition of Dupre [14], the surface and interfacial properties determine the intrinsic or thermodynamic work of adhesion, W, of an interface. For two identical surfaces in contact ... 

In the previous sections it was demonstrated that the stimulus-responsive behavior of ELP was transferred to ELP fusion proteins and even to non-covalently bound moieties, such as proteins, plasmids, and heavy metals, mostly for biomedical and biotechnological applications. The ability of ELPs to reversibly switch their polarity is also of great interest for the development of stimulus-responsive materials. Many approaches have therefore recently been undertaken to integrate ELPs with, for example, polymers, particles, and surfaces. 

In recent years, we have extended the nature of our analysis to include certain statistically defined features of the surface electrostatic potential. Our purpose has been to expand the capabilities of V(r) for quantitatively describing macroscopic properties that reflect non-covalent molecular interactions. This has led to the development of the General Interaction Properties Function (GIPF), described by Eq. (3.7) ... 

Non Covalent Attachment of Antibodies to a Surface by the Inactive Fc Portion... 

In addition to the covalent binding, some methods derived from bioaffinity chromatography can be used for non covalent attachment of antibodies to a surface by the inactive Fc portion. The advantage is that antigen binding sites stay undamaged and accessible for the analytes due to the orientation of antibody with the active Fab portions towards the tested medium. 

Dissolve SPDP in dimethylformamide (DMF) at a concentration of 6.2 mg/ml (makes a 20 mM stock solution). Add 50 pi of the SPDP solution to the 1 ml particle suspension and mix to dissolve. Note The small quantity of DMF in a polymeric particle suspension should not affect particle stability, even if the polymer type is susceptible to swelling in pure DMF. Other particle types, such as metallic or silica based, usually are not affected by organic solvent addition, unless their surfaces are non-covalently coated with a dissolvable polymer. 

Since immunosensors usually measure the signals resulting from the specific immu-noreactions between the analytes and the antibodies or antigens immobilized, it is clear that the immobilization procedures of the antibodies (antigens) on the surfaces of base transducers should play an important role in the construction of immunosensors. Numerous immobilization procedures have been employed for diverse immunosensors, such as electrostatic adsorption, entrapment, cross-linking, and covalent bonding procedures. They may be appropriately divided into two kinds of non-covalent interaction-based and covalent interaction-based immobilization procedures. 

Scheme 1 summarizes four different approaches used to characterize dendrimer structures by photophysical and photochemical probes 1. Non-covalent, inter-molecularly bound interior probes - to study the internal cavities and the encapsulation abilities of dendrimers. 2. Non-covalent, intermolecularly bound surface probes - to study surface characteristics of dendrimers. 3. Covalently linked probes on dendrimer surfaces - to study the molecular dynamics of dendrimers. 4. Covalently linked probes at the dendrimer central core - to study the site isolation of the core moiety and define the hydrodynamic volume of dendrimers by the concentric dendrimer shells. Critical literature in these four categories will be described using representative examples. 

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