Macromolecular complexes of polyampholytes

Kudaibergenov, Sarkyt E.

doi:10.1515/pac-2019-1104

Cited by 8 publications

(9 citation statements)

References 104 publications

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“…Recently, polyelectrolyte gels have received much attention due to their properties. Polyampholytes materials containing both cationic and anionic groups on their macromolecule chains have also been intensively studied [ 12 , 13 ]. Some natural polymers, such as proteins, are also polyampholytes, and their behavior was tested in different applications [ 14 , 15 ].…”

Section: Introductionmentioning

confidence: 99%

Composite Materials Based on Gelatin and Iron Oxide Nanoparticles for MRI Accuracy

Drobotă¹,

Vlad²,

Grădinaru³

et al. 2022

Materials

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The majority of recent studies have focused on obtaining MRI materials for internal use. However, this study focuses on a straightforward method for preparing gelatin-based materials with iron oxide nanoparticles (G–Fe2O3 and G–Fe3O4) for external use. The newly obtained materials must be precisely tuned to match the requirements and usage situation because they will be in close touch with human/animal skin. The biocompatible structures formed by gelatin, tannic acid, and iron oxide nanoparticles were investigated by using FTIR spectroscopy, SEM-EDAX analysis, and contact angle methods. The physico-chemical properties were obtained by using mechanical investigations, dynamic vapor sorption analysis, and bulk magnetic determination. The size and shape of iron oxide nanoparticles dictates the magnetic behavior of the gelatin-based samples. The magnetization curves revealed a typical S-shaped superparamagnetic behavior which is evidence of improved MRI image accuracy. In addition, the MTT assay was used to demonstrate the non-toxicity of the samples, and the antibacterial test confirmed satisfactory findings for all G-based materials.

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Section: Introductionmentioning

confidence: 99%

Composite Materials Based on Gelatin and Iron Oxide Nanoparticles for MRI Accuracy

Drobotă¹,

Vlad²,

Grădinaru³

et al. 2022

Materials

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“…Depending on the nature of the ionic groups, their charge can be either independent of or dependent on the pH of the medium. 23 Polyampholytes can interact with both cationic and anionic species, 25 and some works have already investigated their complexation with ionic surfactants. Systems involving alternating or random polyampholytes combined with fatty acids and cationic and anionic surfactants were explored with emphasis on the solubilization/precipitation behavior of the polyampholyte in the presence of the surfactants and on the balance between intramolecular and intermolecular electrostatic interactions.…”

Section: ■ Introductionmentioning

confidence: 99%

“…Depending on the nature of the ionic groups, their charge can be either independent of or dependent on the pH of the medium . Polyampholytes can interact with both cationic and anionic species, and some works have already investigated their complexation with ionic surfactants. Systems involving alternating or random polyampholytes combined with fatty acids and cationic and anionic surfactants were explored with emphasis on the solubilization/precipitation behavior of the polyampholyte in the presence of the surfactants and on the balance between intramolecular and intermolecular electrostatic interactions. − Of direct relevance for our present study is the investigation by Bekturov et al of the complexation of a diblock polyampholyte, poly(methacry1ic acid)- b -poly(1-methyl-4-vinylpyridinium chloride (PMAA 36 - b -P1M4VPCl 64 ), with two ionic surfactants, hexadecyltrimethylammonium chloride (CTAC) and SDS.…”

Section: Introductionmentioning

confidence: 99%

Versatile Diblock Polyampholytes Can Form Two Types of Charged and Internally Structured Core–Shell Particles by Complexation with Cationic or Anionic Surfactants

2022

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We used diblock poly(acrylic acid)-b-poly(2-dimethylamino ethyl methacrylate) (PAA-b-PDMAEMA) polyampholytes to prepare core–shell complexes with ionic surfactants. The dispersions have been characterized by means of small-angle X-ray scattering (SAXS), cryogenic transmission electron microscopy (Cryo-TEM), dynamic light-scattering, and zeta potential methods. Using cationic or anionic surfactants it is possible to produce particles with either positively or negatively charged shells, both having an internal liquid-crystalline core structure. For the different systems, different preparation protocols were found to be successful to produce stable and reproducible particles. The particle morphologies depend on the surfactant used. Complexes with the cationic surfactant hexadecyltrimethylammonium (CTA+) form oblate particles, while complexes with dodecyl sulfate (DS–) form cylindrical rods. In both complexes, the smallest dimension of the core does not exceed twice the block length of the core-forming polymer block. For the particles with CTA+, nonelectrostatic attractive interactions among the PDMAEMA chains in the shells seem to be present, affecting the particle shape. In both types of particles, the surfactant in the core forms rod-like aggregates, arranged in a two-dimensional hexagonal structure with the surfactant rods aligned with the axis of rotational symmetry in the particle. With charged polymer chains in the shell, the aggregates present a striking stability over time, displaying no change in particle size over the time scale investigated (10 months). Nevertheless, the aggregates are highly dynamic in nature, and their shapes and structures can be changed dramatically in dispersion, without intermediate precipitation, by changes in the composition of the medium. Specifically, a transition from aggregates with cationic surfactant to aggregates with anionic surfactant can be achieved.

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“…To optimize the structure of polybetaines of low fouling characteristics in a variety of environments, it is important to understand the mechanism of the complexation of polybetaines with polycations (P + ), as models of some proteins under physiological conditions. − Previous studies, in particular from the group of Osada and Gong, have established that polybetaine/P + complexes are not necessarily stoichiometric, − since the initiating polybetaine/P + complexes, formed with the release of the polycation counterion, ,− can act as new polycations interacting with the negative charge of polybetaines. The positive charge of the resulting complex causes more polybetaines to associate, while the positive charge of the complex remains, allowing the complex to grow in a cascading manner (Scheme ) and to take part in further “cascading” association with polybetaines, with the release of water molecules.…”

Section: Introductionmentioning

confidence: 99%

“…Since the positive charge of polyzwitterion repeat units is located close to the main chain, the polyzwitterion backbone interferes with the approach of the polyanion, preventing complexation to occur. , The release of counterions during the complexation results in an entropic gain, while the release of water molecules yields an enthalpic gain. Complexation between polyzwitterions and polyelectrolytes, − ,,,− surfactants, − or proteins , has been reported, resulting in coacervates and layer-by-layer structures. Enthalpies of micellization have been reported for surfactants in the presence of polyzwitterions; however, they are mostly unaffected by the presence of the polyzwitterions. − …”

Section: Introductionmentioning

confidence: 99%

Enthalpy of the Complexation in Electrolyte Solutions of Polycations and Polyzwitterions of Different Structures and Topologies

et al. 2021

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Our understanding of the intricate complexation behavior of polyzwitterions with polycations is less than that of polyanion–polycation complexes. In addition, the effect of the topology of polyzwitterions on the complexation of polyzwitterions with polycations is also unclear. We investigated the complexation of methacrylate-based linear, star, and branched poly(sulfobetaine methacrylate)s (PB) with the cationic poly(methacryl oxyethyl trimethylammonium chloride) (PMOTAC), as well as the complexation of linear imidazolium-based polyzwitterions and polycations, by isothermal titration calorimetry (ITC) in saline media. The complexation enthalpies increased with increasing salt concentration and molecular weight up to 0.25 M NaCl. A low degree of branching had little effect on the complexation, whereas highly branched PB did not form complexes. The obtained complexes had nonstoichiometric composition, with high enthalpies per mole of injected polycation due to additional water being released by cascading complexation. Understanding the complexation behavior of polyzwitterions with polycations provides alternatives to traditional polyanion–polycation complexes.

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Macromolecular complexes of polyampholytes

Cited by 8 publications

References 104 publications

Composite Materials Based on Gelatin and Iron Oxide Nanoparticles for MRI Accuracy

Composite Materials Based on Gelatin and Iron Oxide Nanoparticles for MRI Accuracy

Versatile Diblock Polyampholytes Can Form Two Types of Charged and Internally Structured Core–Shell Particles by Complexation with Cationic or Anionic Surfactants

Enthalpy of the Complexation in Electrolyte Solutions of Polycations and Polyzwitterions of Different Structures and Topologies

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