Oligosaccharide Shells as a Decisive Factor for Moderate and Strong Ionic Interactions of Dendritic Poly(ethylene imine) Scaffolds under Shear Forces

Abstract

For better understanding and improving the non-covalent interactions of dendritic core-shell, we evaluated the interactions of hyperbranched poly(ethylene imine) (PEI) decorated with various oligosaccharide shells with water-soluble B vitamins, an estradiol derivative and pantoprazole. Depending on the different properties of the analyte molecules, dendritic core-shell glyco architectures showed (very) weak, moderate and strong interactions with the analyte molecules. Thus, ionic interactions are the strongest driving force for the formation of host-guest complexes. The core-shell glyco architecture is a necessary prerequisite for stable analyte/PEI complexes; the pure hyperbranched PEI did not show any sufficiently strong interactions with neutral, cationic or anionic analytes under the shear forces applied during ultrafiltration of pure aqueous solution without an adjusted pH. Thus, only robust non-covalent interactions between analytes and the dendritic polyamine scaffold of the glycopolymer structure survive this separation step and allow isolation of stable host-guest complexes in aqueous solution.

Characterization of oligosaccharide-functionalized hyperbranched poly(ethylene imine) and their complexes with retinol in aqueous solution

“…The zeta-potential experiments revealed rather small values |f| < 10 mV in the investigated pH-range, suggesting minor cationic charges of the nanostructure. The importance of electrostatic interactions for the uptake of drug-like molecules to PEI-Mal structures has been reported in previous studies [22,27]. However, when it comes to the detailed structure of the PEI-Mal species the impact of pH on the SAXS curves is not detectable, which might be due to the compact structure of dendritic glycoarchitectures.…”

“…Hyperbranched structures such as PEI and PEI-Mal species are expected to function as carriers of drugs and some studies of these systems and their interaction with model drugs have been reported [19,22,27,32]. In the present work, we have investigated the interaction between the strongly hydrophobic model drug retinol (cf.…”

“…Though an enhancement of biocompatibility can be achieved through the incorporation of water-soluble and biocompatible surface groups in the outer shell of the dendritic architecture consisting of poly(propylene imine) (PPI) dendrimers, poly(amido amine) (PAMAM) dendrimers, hyperbranched poly(ethylene imine) (PEI), and other dendritic scaffolds [13][14][15][16][17][18]. In recent studies [19][20][21][22][23], the coupling of mono-and oligosaccharide units has successfully been accomplished. Hence, these dendritic glycoarchitectures have been considered as nanocarriers for drugs [19,20,23].…”

Glycopolymer Polyelectrolyte Multilayers Composed of Heparin and Maltose‐Modified Poly(ethylene imine) as a Strong/Weak Polyelectrolyte System for Future Drug Delivery Coatings: Influence of pH and Sugar Architecture on Growth of Multilayers and Multilayer Swelling and Stability

“…A mean value of about 55 nm of three scratch experiments was evaluated. Thus, the AFM measurement can be used as a direct and accurate method to detect the layer thickness because a direct AFM tip contact with the substrate and the coated surface is given . The resulted thickness was not totally away from that was detected by ellipsometry.…”

Effect of the Structure of Therapeutic Adenosine Analogues on Stability and Surface Electrostatic Potential of their Complexes with Poly(propyleneimine) Dendrimers

“…The advantages of AF4 include a broad separation range accessible by a single channel and significantly reduced risk of shear degradation . The application of this method constitutes a significant extension of our previous studies on the complexation patterns of glycosylated branched polymers . The experiments have been carried out for PPI‐Mal OS G4 at pH 7.4 (physiological conditions) and 5.8 (acidic cellular compartment) ( Figure ).…”