Polymer, complementary

Polymer complexes associated with two or more complementary polymers are widely used in potential applications in the form of particles, hydrogels, films, and membranes. In particular, a polyion complex (PIC) can be easily formed when oppositely charged polyelectrolytes are mixed in aqueous solution and interact via... 

Figure 5.11 The three distinct classes of hydrogen bonded polymer networks (a) self-associative polymer network, (h) polymer network synthesized via the use of complementary linker molecules, and (c) complementary polymer hlends.

Now add to this solution complementary polymer P which is capable of forming the equimolar (stoichiometry is not important since it must be only constant) polycomplex with P, its concentration being m < m°, then part P will bind in a polycomplex and the distribution function of P ws( x. ) remaining in the solution, normalized to m° — m, on the whole will not be identical to the initial one, i.e.,... 

An alternative to an extensive inorganic structure is an extensive organic one. Candidates for this could include any number of polymers. One approach is to make self-assembled capsules from complementary polymers that form layer by layer (LbL) vesicle-like structures [26], This has been achieved by templating the co-assembly of polymers around a removable core. The alternation of polymers with opposite charges allows the composition and thickness of the artificial cell walls to be controlled. The size of the core determines if the resulting capsule is a model for a cell or a smaller capsule like an organelle within a cell. The porous nature of the polymer allows chemical species to enter and leave the capsule but the potential for capsule growth and division, even with the presence of polymers in the external solution is very limited. 

The molecular weight of the backbone polymer is another important factor. No interactions between the monomer and dimer models were observed under the conditions examined, nor was there any apparent interaction between the monomer model and the polymer. Interactions between the dimer models and their complementary polymers occur only at higher concentrations. In order to realize a stable complex formation, the molecular weight of the polymers should be high enough, as in the case of polynucleotides39. ... 

It was also detected that the interaction tends to become weaker with decreasing thymine content of the polymer. The value of hypochromidty for PLL-A-67 with PLL-T-79 was 2%, and no significant interaction was observed for the system of PLL-A-67 and PLL-T-65. Similarly to these systems, the interaction between PLL-A-67 and PLL-Us is also influenced by the uradl content. It was suggested that a weak interaction between complementary polymers containing a low content of bases may be caused mainly by a low helidty. 

From these facts, it is concluded that the polymer complexes are formed by specific base pairing between pendant adenine and thymine or uracil units of poly-L-lysine derivatives retaining their helical conformations (Fig. 26). The lowering of the base content in the polymers results in the decrease of the helical structure and also in the decrease of interactions with the complementary polymer. 

Intermacromolecular hydrogen bonds, interactions of non-polar groups in water, and electrostatic interactions between macromolecules lead to the formation of polymer complexes consisting of cooperatively bonded continuous sequences of monomer units of complementary polymer chains or to the formation of poly-... 

In 1953 James Watson and Francis Crick proposed a model for the structure of the DNA molecule, based on data about the size and function of the molecule. They built a physical model of their proposed structure in order to help them understand how the molecule functions. Their proposed structure, which consisted of a double helix of two complementary polymer chains, enabled them to predict how DNA replicates. 

This device employs single-stranded poly(adenylic acid) [poly(A)] as the chemical recognition agent. This species selectively recognizes its complementary polymer, poly(U), through hybridization to form a double-stranded nucleic acid. The poly(A) is immobilized onto the activated surface of a quartz piezoelectric crystal, which is a mass-sensitive transducer. Electric dipoles are generated in anisotropic materials (such as quartz crystals) subjected to mechanical stress, and these materials will... 

Bttnemann, MUller and co-workers (83) looked for polymers which can bind distinct sequences of DNA. They used the target DNA as the template to synthesize the complementary polymer. To the target DNA a mixture of base-specific dyes carrying polymerizable acrylic derivatives was bound. It was then possible to copolymerize these acrylic derivatives while bound to a native DNA in an aqueous solution. The resulting polymers were separated from the template DNA and assayed for DNA-binding specificity (8A). It was possible with these polymers to strongly inhibit transcription from that DNA which had served as template for polymer synthesis. 

Valignat [54] demonstrated that this powerful assembly method could be used to lock reversibly directed assembled (with optical tweezers) microspheres grafted with complementary polymer brushes into a prearranged suprastructure (see Fig. 10). 

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