Molecular and structural analysis via hydrodynamic methods: Cationic poly(2-aminoethyl-methacrylate)s

Beyond Gene Transfection with Methacrylate-Based Polyplexes—The Influence of the Amino Substitution Pattern

“…30 However, the AF4 measurement will always tend to underestimate the values for dispersitiy in comparison with other MALLS coupled techniques due to the architecture of the AF4 channel including a membrane with a cutoff of 10 kDa. 31 In additional titration experiments, the pK a values of the homo-and copolymers PD to PDMA were determined to be in the range from pH 7.45 to 8.40 (Table 2). The later used physiological ionic strength was mimicked by the addition of 150 mM NaCl.…”

“…With regard to the missing appropriate size exclusion standards (dextrane used for aqueous SEC) for cationic methacrylate systems the determination of the molar masses and the dispersities is more accurate by utilizing the MALLS detection . However, the AF4 measurement will always tend to underestimate the values for dispersitiy in comparison with other MALLS coupled techniques due to the architecture of the AF4 channel including a membrane with a cutoff of 10 kDa …”

Conformational properties of biocompatible poly(2-ethyl-2-oxazoline)s in phosphate buffered saline

“…6 Conformational analysis can be performed by a combination of rigorous hydrodynamic methods such as analytical ultracentrifugation, translational diffusion, and intrinsic viscosity measurements through Kuhn-Mark-Houwink-Sakurada (KMHS) scaling relations. [7][8][9][10] A broad range of molecular weights and low dispersity is mandatory for such a study. Therefore, such in depth knowledge on the conformational properties of PEtOx is absent as for many years high molar mass defined poly(2oxazoline)s were synthetically inaccessible due to the sensitivity of the cationic ring-opening polymerization to nucleophilic impurities in combination with unavoidable intrinsic chain transfer side reactions (CROP).…”

Incentives of Using the Hydrodynamic Invariant and Sedimentation Parameter for the Study of Naturally- and Synthetically-Based Macromolecules in Solution

“…Color and symbol assignments for naturally-based macromolecules: Black-Rigid, Xanthan (squares) [25], Chitosan (circles) [26,27], Schizophyllan (triangles up) [28]; Blue-Semi-Flexible, Pectin (squares) [29,30], Chitosan (circles) [31][32][33][34], Chitin (triangles up) [35], Cellulose (triangles down) [12,[36][37][38][39][40][41], Heparin (diamonds) [42], Ficoll400 (triangles left) [43]; Green-Flexible, Glucan (squares) [44], Mannan (circles) [45], Pullulan (triangles up) [46], Carrageenan (triangles down) [47], Polyvinylsaccharide (diamonds) [48,49]; Red-Branched, Glucan (squares) [50], Lysin (circles) [51]. Color and symbol assignments for synthetically-based macromolecules: Blue-Semi-Flexible, Polyelectrolyte (squares), cationic [52]; Green-Flexible, Polyelectrolyte (squares), cationic [53][54][55][56][57][58][59][60][61][62], anionic [63], Poly(ethylene) glycol (PEG) (circles) [14], Poly(2-alkyl-2-oxazoline) (POx)/Poly(oligo(2-ethyl-2-oxazoline)) based polymers (triangles up) [13,…”

“…Polyelectrolytes are inherently difficult to study. The sufficient compensation of macromolecular backbone charge effects, necessary to reduce difficulties in the measurements by sedimentation velocity experiments and the typically observed non-linearity of the Huggins-and Kraemer extrapolation procedures for estimations of the intrinsic viscosity, [η], are critical [54,55,68]. At present, the detailed hydrodynamic study and interrelation of hydrodynamic characteristics within the framework of the hydrodynamic invariant, A 0 (Equation (12)), or sedimentation parameter, β s (Equation 14), are still awaiting validation and establishment.…”