Formation and Properties of Positively Charged Colloids Based on Polyelectrolyte Complexes of Biopolymers

Langmuir ◽  
2004 ◽  
Vol 20 (18) ◽  
pp. 7766-7778 ◽  
Author(s):  
Christophe Schatz ◽  
Jean-Michel Lucas ◽  
Christophe Viton ◽  
Alain Domard ◽  
Christian Pichot ◽  
...  
Keyword(s):  
Polyelectrolyte Complexes ◽  
Charged Colloids ◽  
Positively Charged

Synthetic imogolite: properties, synthesis and possible applications

Clay Minerals ◽  
1983 ◽  
Vol 18 (4) ◽  
pp. 459-472 ◽  
Author(s):  
V. C. Farmer ◽  
M. J. Adams ◽  
A. R. Fraser ◽  
F. Palmieri
Keyword(s):  
Mechanical Stability ◽  
Surface Acidity ◽  
Outer Diameter ◽  
Charged Colloids ◽  
Inner Surface ◽  
Forming Characteristics ◽  
Inner Diameter ◽  
Anionic Detergents ◽  
Positively Charged ◽  
Long Chain

AbstractThe unique properties of imogolite are closely related to its structure, which is a tube of 23–27 Å outer diameter and ∼10 Å inner diameter, with an AIOH outer surface and SiOH inner surface. Acid dispersions contain the long, positively-charged tubes as isolated units or small bundles, which form bulky gels in alkali, and flocculate with negatively-charged colloids, polyvalent anions, and long-chain anionic detergents. Sorption properties are associated with the 10 Å intra-tube pores and with inter-tube channels of variable dimensions. Surface acidity is less than that of layer-silicate clays. The chemical and mechanical stability, biological activity, film- and fibre-forming characteristics, and conditions of synthesis are reviewed, on the basis of both new and published findings. Areas of potential application are indicated.

scholarly journals Tuning the order of colloidal monolayers: assembly of heterogeneously charged colloids close to a patterned substrate

Soft Matter ◽  
2018 ◽  
Vol 14 (40) ◽  
pp. 8119-8136 ◽  
Author(s):  
Emanuele Locatelli ◽  
Emanuela Bianchi
Keyword(s):  
Patterned Substrate ◽  
Patterned Surface ◽  
Polar Caps ◽  
Charged Colloids ◽  
Positively Charged

We study the behavior of negatively charged colloids with two positively charged polar caps close to a planar patterned surface.

scholarly journals Hyaluronan/Diethylaminoethyl Chitosan Polyelectrolyte Complexes as Carriers for Improved Colistin Delivery

2021 ◽  
Vol 22 (16) ◽  
pp. 8381
Author(s):  
Natallia V. Dubashynskaya ◽  
Sergei V. Raik ◽  
Yaroslav A. Dubrovskii ◽  
Elena V. Demyanova ◽  
Elena S. Shcherbakova ◽  
...  
Keyword(s):  
Delivery System ◽  
Polyelectrolyte Complex ◽  
Multidrug Resistant ◽  
Water Soluble ◽  
Hydrodynamic Diameter ◽  
Polyelectrolyte Complexes ◽  
Negative Surface ◽  
Negative Surface Charge ◽  
Positively Charged

Improving the therapeutic characteristics of antibiotics is an effective strategy for controlling the growth of multidrug-resistant Gram-negative microorganisms. The purpose of this study was to develop a colistin (CT) delivery system based on hyaluronic acid (HA) and the water-soluble cationic chitosan derivative, diethylaminoethyl chitosan (DEAECS). The CT delivery system was a polyelectrolyte complex (PEC) obtained by interpolymeric interactions between the HA polyanion and the DEAECS polycation, with simultaneous inclusion of positively charged CT molecules into the resulting complex. The developed PEC had a hydrodynamic diameter of 210–250 nm and a negative surface charge (ζ-potential = −19 mV); the encapsulation and loading efficiencies were 100 and 16.7%, respectively. The developed CT delivery systems were characterized by modified release (30–40% and 85–90% of CT released in 15 and 60 min, respectively) compared to pure CT (100% CT released in 15 min). In vitro experiments showed that the encapsulation of CT in polysaccharide carriers did not reduce its antimicrobial activity, as the minimum inhibitory concentrations against Pseudomonas aeruginosa of both encapsulated CT and pure CT were 1 μg/mL.

scholarly journals Polyelectrolyte Complexes of Natural Polymers and Their Biomedical Applications

Polymers ◽  
2019 ◽  
Vol 11 (4) ◽  
pp. 672 ◽  
Author(s):  
Masayuki Ishihara ◽  
Satoko Kishimoto ◽  
Shingo Nakamura ◽  
Yoko Sato ◽  
Hidemi Hattori
Keyword(s):  
Biomedical Applications ◽  
Electrostatic Interactions ◽  
Biological Activities ◽  
Wound Dressings ◽  
Natural Polymers ◽  
Tissue Adhesives ◽  
Chitosan Hydrogel ◽  
Polyelectrolyte Complexes ◽  
Micro Particles ◽  
Positively Charged

Polyelectrolyte complexes (PECs), composed of natural and biodegradable polymers, (such as positively charged chitosan or protamine and negatively charged glycosaminoglycans (GAGs)) have attracted attention as hydrogels, films, hydrocolloids, and nano-/micro-particles (N/MPs) for biomedical applications. This is due to their biocompatibility and biological activities. These PECs have been used as drug and cell delivery carriers, hemostats, wound dressings, tissue adhesives, and scaffolds for tissue engineering. In addition to their comprehensive review, this review describes our original studies and provides an overview of the characteristics of chitosan-based hydrogel, including photo-cross-linkable chitosan hydrogel and hydrocolloidal PECs, as well as molecular-weight heparin (LH)/positively charged protamine (P) N/MPs. These are generated by electrostatic interactions between negatively charged LH and positively charged P together with their potential biomedical applications.

Microscopics of Complexation between Long DNA Molecules and Positively Charged Colloids

2002 ◽  
Vol 89 (8) ◽  
Author(s):  
K. Keren ◽  
Y. Soen ◽  
G. Ben Yoseph ◽  
R. Gilad ◽  
E. Braun ◽  
...  
Keyword(s):  
Dna Molecules ◽  
Charged Colloids ◽  
Positively Charged

SILICON THERMAL WATERS AND THEIR IMPACT ON HUMAN HEALTH

2021 ◽  
pp. 96-102
Author(s):  
Tkachenko A.V. ◽  
Slinkova T.A. ◽  
Shipkova L.N. ◽  
Kharlashkina P.S.
Keyword(s):  
Heavy Metals ◽  
Human Health ◽  
Silicic Acid ◽  
Thermal Water ◽  
Thermal Waters ◽  
Silicate Content ◽  
Charged Colloids ◽  
Medical Indications ◽  
Low Solubility ◽  
Positively Charged

The unique mineral thermal water has been researched. The composition of thermal water has been studied, its effect on human health has been described. This thermal water belongs to the hydrocarbonate-silicon type. The total silicate content is more than 120 mg/l, which is one of the highest rates for thermal springs in our country. The low solubility of silicic acid is compensated by the ability of silicon to form positively charged colloids, which neutralize microorganisms and promote the precipitation of heavy metals. Perhaps this factor is responsible for the insignificant presence of heavy metals in water. The medical indications and contraindications for this type of balneological treatment are described.

scholarly journals Complexation and coacervation of like-charged polyelectrolytes inspired by mussels

2016 ◽  
Vol 113 (7) ◽  
pp. E847-E853 ◽  
Author(s):  
Sangsik Kim ◽  
Jun Huang ◽  
Yongjin Lee ◽  
Sandipan Dutta ◽  
Hee Young Yoo ◽  
...  
Keyword(s):  
Electrostatic Interactions ◽  
Short Range ◽  
Self Healing ◽  
New Paradigm ◽  
Polyelectrolyte Complexes ◽  
Underwater Adhesion ◽  
Complex Coacervate ◽  
Low Interfacial Tension ◽  
Oppositely Charged ◽  
Positively Charged

It is well known that polyelectrolyte complexes and coacervates can form on mixing oppositely charged polyelectrolytes in aqueous solutions, due to mainly electrostatic attraction between the oppositely charged polymers. Here, we report the first (to the best of our knowledge) complexation and coacervation of two positively charged polyelectrolytes, which provides a new paradigm for engineering strong, self-healing interactions between polyelectrolytes underwater and a new marine mussel-inspired underwater adhesion mechanism. Unlike the conventional complex coacervate, the like-charged coacervate is aggregated by strong short-range cation–π interactions by overcoming repulsive electrostatic interactions. The resultant phase of the like-charged coacervate comprises a thin and fragile polyelectrolyte framework and round and regular pores, implying a strong electrostatic correlation among the polyelectrolyte frameworks. The like-charged coacervate possesses a very low interfacial tension, which enables this highly positively charged coacervate to be applied to capture, carry, or encapsulate anionic biomolecules and particles with a broad range of applications.

scholarly journals Polyelectrolyte Complexes Based on Chitosan and Natural Polymers

2016 ◽  
Vol 4 (1) ◽  
pp. 100 ◽  
Author(s):  
Alef Mustafa ◽  
Aneta Tomescu ◽  
Emin Mustafa ◽  
Melat Cherim ◽  
Rodica Sîrbu
Keyword(s):  
Production Cost ◽  
Dosage Forms ◽  
Low Ph ◽  
Natural Polymers ◽  
Polyelectrolyte Complexes ◽  
Ph Values ◽  
Different Types ◽  
Low Toxicity ◽  
The Subject ◽  
Positively Charged

For many years chitosan has been the subject of interest for its use in different medical fields due to its appealing properties such as biocompatibility, biodegradability, low toxicity and relatively low production cost from abundant natural sources. Chitosan is positively charged at low pH values, so it is spontaneously associated with negatively charged polyions in solution to form polyelectrolyte complexes. These chitosan based polyelectrolyte complexes exhibit favourable physicochemical properties with preservation of chitosan’s biocompatible characteristics. These chitosan based complexes are a good candidate for excipient materials for the design of different types of dosage forms. The aim of this review is to describe polyelectrolyte complexes of chitosan with selected natural polyanions and also to indicate some of the factors that influence the formation and stability of these formed complexes.

Sign in / Sign up

Export Citation Format

Share Document