Biohybrid structures consisting of biotinylated glycodendrimers and proteins: influence of the biotin ligand's number and chemical nature on the biotin–avidin conjugation

Abstract

We present the bioconjugation of avidin as a central and/or bridging building block with mono-, bi-and tetravalent biotinylated glycodendrimers to fabricate defined supramolecular nanostructures for future (bio)medical applications. For this purpose mono-, bi-and tetravalent biotinylated glycodendrimers, decorated with short alkyl-linked or long PEG-linked biotin ligands, were synthesized and characterized by NMR, IR and mass spectrometry and HABA displacement assay. Various techniques (UV/Vis, DLS, TEM, LILBID-MS and AF4) were used in order to obtain information about the structural properties of different conjugates of avidin and mono-, bi-and tetravalent biotinylated glycodendrimers. The biotin ligand's spacer length, its chemical structure and the degree of biotin functionalization are essential parameters in the formation of nanostructures with avidin having a controlled composition and size dimension up to 100 nm. Biohybrid structures with avidin as a central unit require monovalent glycodendrimers with PEG-linked biotin, while bi-and tetravalent glycodendrimers with short alkyl-linked biotin ligands are more efficient than their counterparts with longer PEG-biotin ligands in the fabrication of defined biohybrid structures (B up to 100 nm) with avidin as a bridging unit. The most dominating key issue, combined with other conjugation issues, is the optimal ligand-receptor stoichiometry to fabricate biohybrid structures with diameter of <20, <30 or up to 100 nm.

Dendritic glycopolymers based on dendritic polyamine scaffolds: view on their synthetic approaches, characteristics and potential for biomedical applications

“…80,83,176 One final consideration is directed to the efficiency of the applied one-pot reactions mentioned above to establish the desired dendritic glycoconjugates. 10,[108][109][110][111][112][113][114][115][116][117][118] The conversion of dendritic polyamine scaffold based on amidation, phenyl isothiocyanate derivatives and lactone derivatives is more or less quantitative ( Fig. 6) when following the experimental protocols.…”

“…1,33,35 On the other hand dendritic glycoconjugates, carbohydrate-containing dendronized polymers, and hybrid materials of various polysaccharides over the last year have been also established in various application fields. Thus they have been used as drug delivery systems, 10, biosensors, 15,16,19,[96][97][98][99][100][101] and imaging agents, 1,18,[102][103][104][105][106] but also as a base in biohybrid structures obtained through non-covalent and biological conjugation, 91,92,107,108 as sugarballs for H-bond-active therapeutics and diagnostics for brain disease, [109][110][111][112][113][114][115][116][117][118] as supramolecular structures by (defined) self-assembly [119][120][121] or host-guest interactions, 122 and in thin film technology for introducing specific interactions with small analyte molecules or proteins. 123,124 The PPI, Lys, and PAMAM polyamine dendrimers, but also branched poly(ethyleneimines) (PEI) are the dominating dendritic core scaffolds to realize the desired dendritic glycopolymers for these growing research fields ( Fig.…”

From 1D Rods to 3D Networks: A Biohybrid Topological Diversity Investigated by Asymmetrical Flow Field-Flow Fractionation

“…Taking into account that not all four binding sites in avidin can be occupied due to steric requirement of participating biotinylated glycodendrimers during biohybrid formation. 7 precisely determined channel geometry and height as well as flow rates. 45,47 Furthermore, it should be considered that calculation is limited to elution in normal mode.…”

Size Separation Techniques for the Characterisation of Cross-Linked Casein: A Review of Methods and Their Applications

“…For homogeneous hard sphere the ratio is equal to 0.775, for linear random coil is between 1 and 2, and for elongated conformations the ratio is up to 2 [200]. The determination of the diffusion coefficient and thus the hydrodynamic radius is also possible from the AF4 elution time (see Section 5.1, Equation (3)); however, both approaches possess advantages and limitations that were treated in depth in the bioconjugation of synthetic macromolecules and proteins [177,[201][202][203][204][205].…”