Using Dextran-encapsulated gold nanoparticles as insulin carriers to prolong insulin activity

Aim: Diabetes mellitus is commonly treated with painful Insulin injections. We aim to explore drug carriers that can prolong Insulin activity.

Materials & methods: Dextran-encapsulated gold NPs (AuNPs@Dextran) that can bind with Insulin are used as Insulin carriers. The affinity (K _d = ∼42 pM) between Insulin and Insulin receptors on the cells is much higher than that (K _d = ∼4.02 μM) of Insulin and AuNPs@Dextran. Thus, Insulin released from the AuNP@Dextran-insulin conjugates to maintain kinetic equilibrium and prefers to bind to the Insulin Receptor. The slow release of Insulin from the AuNP@Dextran-insulin conjugates facilitates the lasting of Insulin activity.

Results & discussion: AuNP@Dextran-insulin conjugates can prolong Insulin activity to 12 h, whereas free form Insulin loses activity after 4 h in adipocyte cells.

Conclusion: AuNPs@Dextran are suitable carriers that can prolong Insulin activity.