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Updated: Jun 5, 2026

Study of Short Peptide Adsorption on Solution Dispersed Inorganic Nanoparticles Using Depletion Method
Published on: April 11, 2020
Influence of acylation on the adsorption of insulin to hydrophobic surfaces
Charlotte Pinholt1, Susanne Hostrup, Jens Thostrup Bukrinsky
1Department of Pharmaceutics and Analytical Chemistry Faculty of Pharmaceutical Sciences, University of Copenhagen, DK-2100 Copenhagen, Denmark. cp@farma.ku.dk
Purpose:
To study the effect of acylation on the adsorption of insulin to hydrophobic polystyrene beads.
Methods:
Adsorption isotherms for adsorption of insulin and acylated insulin to hydrophobic polystyrene beads were established, and the adsorption of the two proteins was compared further with isothermal titration calorimetry. In addition, the secondary structure and the association behavior of the two proteins were studied with circular dichroism.
Results:
Insulin and acylated insulin adsorbed with high affinity to the hydrophobic polystyrene beads. More acylated insulin molecules than insulin molecules adsorbed per unit surface area from solutions containing monomer-dimer mixtures of acylated insulin and insulin, respectively. In contrast, no difference was observed in the number of insulin and acylated insulin molecules adsorbing per unit surface area, when adsorption occurred from solutions containing monomer-dimer-hexamer mixtures.
Conclusion:
The influence of acylation on the adsorption behavior of insulin depends on the association degree of insulin, possibly due to a greater difference in hydrophobicity between monomeric insulin and acylated insulin than between the hexameric forms of these two proteins.
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