Fast-acting insulin analogs are designed to limit hexamer formation, favoring monomeric or dimeric states that facilitate rapid absorption into the bloodstream. Consistency in this structural organization is critical for achieving predictable pharmacokinetics. Small-Angle X-ray Scattering (SAXS) provides insights into the molecular-level organization of insulin, which is instrumental for quality control of these formulations.
To control the molecular organization in fast-release insulin formulations, we conducted SAXS characterization of commercial batches at a concentration of 3.5 mg/mL.
The figure below presents the reconstructed pair-distance distribution function (PDDF) for the particular batch. The determined radius of gyration (Rg) of 2.0 ± 0.2 nm suggests the presence of oligomers, despite the modifications intended to enhance monomer stability.
