Study on swelling and drug releasing behaviors of ibuprofen-loaded bimetallic alginate aerogel beads with pH-responsive performance

Bimetallic alginate aerogel beads were prepared by ionotropic gelation method with Ca2+-Ba2+ bimetallic solution and ibuprofen was loaded as a model drug. The swelling and drug releasing behaviors of the beads, especially the influence of barium, were investigated in artificial gastric and intestinal fluids. The results showed that these beads presented higher encapsulation efficiency due to the special structure of aerogel, and barium was beneficial for the more stable structure and drug releasing behavior. The lower swelling capacity of bimetallic beads was observed than monometallic beads. A rapid high-level releasing of ibuprofen was achieved in artificial intestinal fluid, which was up to 96.9% within 1 h, while ibuprofen releasing was avoided in artificial gastric fluid effectively. The drug releasing mechanism of these beads was explored in detail. In the bimetallic crosslinking system, Ba2+ presented a special effect on alginate beads with more sensitive pH response performance. Thus, these beads had more widely potential as a site-specific delivery system, especially for intestinal therapy.

Automated summary

Bimetallic alginate aerogel beads with Ca2+-Ba2+ solution showed higher encapsulation efficiency and more stable structure in drug releasing. The swelling capacity of bimetallic beads was lower than monometallic beads, and a rapid high-level releasing of ibuprofen was achieved in artificial intestinal fluid.